Agriculture Issues

8/13/2019 Agriculture Issues

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Varietal Evaluation Trial of Wheat Genotypes Against Wheat Rusts Disease

and Its monitoringat Farmers Field

Rajan Shrestha

Mini-Thesis Submitted to

Purbanchal University

Faculty of Science and Technology

Himalayan College of Agricultural Sciences and Technology

Kathmandu, Nepal

(In partial fulfillment of the requirements for the degree of Bachelor of Science (Honours)

Agriculture

(B.Sc. Ag. Hons.) - Plant Protection

August,August2013


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Vijaya needs further testing for its resistance against rust although it is a very recently released

variety.


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Table of Contents

ACKNOWLEDGEMENT ............................................................................................................. i

ABSTRACT ................................................................................................................................... ii

Table of Contents ......................................................................................................................iviii

ACROYNMS .............................................................................................................................. viv

List of Tables ................................................................................................................................. 1

List of Figures (1) and Photographs (A) ..................................................................................... 2

INTRODUCTION.......................................................................................................................43

Background ............................................................................................................................... 43

Wheat Status in Nepal ............................................................................................................... 43

Features about World and Nepalese Wheat Cultivation ........................................................... 54

Wheat Research and its importance in Nepal; .......................................................................... 76

Wheat Varieties in Nepal .......................................................................................................... 76

Wheat Diseases ....................................................................................................................... 109

Wheat Rusts Diseases................................................................................................................ 11

Leaf Rust (Brown Rust)............................................................................................. 1211

Stem Rust (Black Rust).................................................................................................. 13

Stripe Rust (Yellow Rust).......................................................................................... 1615

Statement of the Problem ...................................................................................................... 1817

Objectives .............................................................................................................................. 1817

General objective......................................................................................................... 1918

Specific objectives........................................................................................................ 1918

Justification of the Study ....................................................................................................... 1918

Scope of the Study................................................................................................................. 2019

Major Assumptions ............................................................................................................... 2120


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LITERATURE REVIEW ......................................................................................................2221

Wheat Rusts in Nepal ............................................................................................................ 2221

Wheat Rusts in South Asia and Some Third Countries ........................................................ 3433

Wheat Rust Control and Management Aspects..................................................................... 3635

Materials and Methods ........................................................................................................... 3938

Site of Study .......................................................................................................................... 3938

Monitoring site ............................................................................................................... 3938

Research/trial location ................................................................................................... 3938

Duration of Study .................................................................................................................. 3938

Wheat Disease monitoring .................................................................................................... 3938

Wheat Varietal Evaluation Trial ........................................................................................... 3938

Recording Rusts in the Field ................................................................................................. 3938

OBSERVATION AND FINDINGS .......................................................................................4342

RESULT AND DISCUSSIONS .............................................................................................5756

Result on Wheat Rusts Monitoring at Different Locations in Farmers Field...................... 5756

Discussion on Wheat Rusts Monitoring Results. .................................................................. 6059

Result on Wheat Genotypes Evaluation 2012/13 Trial ......................................................... 6261

Discussion on results of Wheat genotypes Evaluation.......................................................... 6563

Summary .................................................................................................................................. 6866

Conclusions and Suggestions ................................................................................................. 7068

Annexes .................................................................................................................................... 7270

References .................................................................................................................................... 78


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ACROYNMS

ABD = Agriculture Botany Division

AnnR = Annual Report

ARC= Agriculture Research Centre

ARS = Agriculture Research Station

B.S. = Bikram Sambat

B.Sc. Ag. Hons. = Bachelor in Agricultural Science (Honours.)

BYDV =

C.O. = Causal Organism

CIMMYT = International Centre for Maize and Wheat Improvement

CS = Covered Smut

CVT = Co-ordinated Varietal Trial

dd/mm/yy = Date Month Year

DOA = Department of Agriculture

FB = Foliar Blight

ft. = Feet

FY = Fiscal Year

FYM = Farm Yard Manure

H = High

HICAST = Himalayan College of Agricultural Science and Technology

HLB = Helminthosporium Leaf Blight

L = Low

LR = Leaf Rust

LR = Leaf Rust

Lr = Leaf rust resistant gene

LS = Loose Smut


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M = Moderate

Masl = Mean average sea level

MOAD = Ministry of Agriculture Development

MR = Moderately Resistant

MS = Moderately Susceptible

NA = Not Available

NARC = Nepal Agricultural Research Council

NARSC = National Agricultural Research And Service Center

NDN = National Disease Nursery

Nepal Agric. Res. J., = Nepal Agriculture Research Journal

NK = Not known

NWDP= National Wheat Development Program

NWRP = National Wheat Research Program

PAC

PM = Powdery Mildew

PPD = Plant Protection Division

R = Resistant

R = Resistant

RARA

RH = Relative Humidity

S = Susceptible

SR = Stem Rust

Sr = Stem rust resistant gene

SRTN= Stem Rust Trap Nursery

Tmax = Maximum Temperature

Tmin = Minimum Temperature


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TMR = Trace Moderately Resistant

TMS = Trace Moderately Susceptible

tons/ha = Tone per hectare

TR = Trace Resistant

WRP = Wheat Research Program

WVD = Wheat Varietal Display

Yr = Yellow rust resistant gene

YR =Yellow Rust


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List of Tables

Table 1. Released Wheat Cultivars in Nepal

Table 2. List of Wheat Rusts Disease recorded in Nepal and their distribution.

Table 3. Environmental condition required for the wheat rusts

Table 4. Wheat Rust Monitoring Data at different places in the Farmers Field

Table 5. Cultural Details Adopted by Farmers In Wheat Cultivation

Table 6. Data on Farmers Details

Table 7. Rust Disease Scoring AT Wheat Evaluation Trial 2012/13, Khumaltar

Table 8. Incidence and Severity Levels of the Yellow rust and Leaf rust disease

Table 9. Metrological Information During The Wheat SeasonKhumaltar


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List of Figures (1) and Photographs (A)

Figure A. Map of Research Site, Khumaltar, Lalitpur.

Figure B. Map of the Wheat Monitoring AT Farmers Field

Figure C. Some of Wheat Genotypes in the Evaluation Trial

Figure D. Author with famer at Dadhikot

Figure E. Glume Infection At Farmers Field

Figure F. Severe leaf rust at Balkot

Figure G. Author in evaluation trial

Figure H. Severe yellow rust in farmers field at Balkot

Figure 1. Distribution of the sample size by location wise

Figure 2. Distribution of Wheat Rusts in Farmers Field

Figure 3. Knowledge on farmers about wheat disease in history

Figure 4. Monthly temperature data during wheat season

Figure 5. Relative Humidity and R during the wheat- growing season


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INTRODUCTION

Background

The cultivation of wheat (Triticum spp.) dates back far into history as one of the first

domesticated food crops and for being the basic staple food of the major civilization of Europe,

West Asia and North Africa for 8000 years.(Curtis, 2002). Wheat is special in several ways and

grown on more than 240 million ha - larger than any other crop and world trade is greater than

for all others crops combined. China has the largest land area devoted to wheat cultivation

followed by the USA, India and the Russian Federation.

Wheat (Triticum aestivum),although being relatively new cereal crop in Nepal, occupies third

position among the cereal grains after rice and maize. (Annual Report 1987/88 NARSC).

However wheat is the most preferred food commodity second to rice in Nepal . (Tripathi and

etalothers, 2012). It is traditional crop particularly in the hills of the mid and far-western region

where still some local landraces are under cultivation. Until the early 60s, wheat cultivation was

limited predominantly to this part of the country. However with the introduction of the Semi-

dwarf varieties from Mexico during the mid-sixties hasdled to tremendous increment in the area

and production too in the Terai and other areas.(NARSC Annual Report 1987/88).

Wheat Status in Nepal

The cultivation of the wheat is done in an area of 7, 65,317 ha with the production of 18, 46,142

Mt and yield of 2412 kg/ha. The area of wheat cultivation have increased by 29.2% since

1990/91 (592740 ha) and productivity of the crop has escalated by 71.064% during the same

period in comparison with yield of 1410 kg/ha in FY 1990/91. District wise Dhanusa is the

largest while Dolpa is smallest in terms of wheat acreage cover. Meanwhile Rupandehi district

stands top in account to total production producing 106750 Mt and Dolpa lowest producer

producing 605 Mt in the FY 2011/12. The productivity of the wheat is highest in Lalitpur district

and least in Sindhupalchok district with 3618 and 1000 kg/ha respectively -. 97.63 percent

(747190 ha) of total area is covered by improved seeds and 2.36% (18085 ha) by local seeds.

The irrigated wheat land accounts 485045 ha sharing 63.36% and 280230 ha (36.61%) land is

rainfed in condition.(MOAD, 2011/12).

Formatted:Justified


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The wheat grown in Nepal is of spring types. They are sown in April or May and harvested in

AugustSeptember. However in Nepal and India spring wheat is grown in winter. It is only in

some high hills in Nepal viz., Nigale, Dandapakhar, Mustang, and Rasuwa etc. that wheat is

grown in winter as well as in summer. Wheat is utilized in the form of flour or whole-meal and

consumed in many forms such as noodles, pancakes, flatbreads, leavened breads and rolls,

porridge etc. (Joshi and etalet al. 1988). It is estimated that nearly two thirds of wheat

production in the world is used for food; the remaining one third is used for feed, seed and non-

food applications. Wheat based foods are the major source of energy, protein and various,

vitamins and minerals.(Ranhotra, 1999).

Features about World and Nepalese Wheat Cultivation

Wheat serves as a staple food for more than 1 billion people in more than 45 countries of

the world.

Wheat contributes more calories (20%) and more protein to the worlds diet than any

other food crop.

Winter wheat can survive temperature as low as -300C whereas spring wheat can be sown

in any season.

Wheat is grown between the latitudes of 300 and 600 N and 270 and 400 S. Mostly in

temperate zones as wheat is basically a crop of the temperate region.(Joshi and Regmi,

1988).

Wheat is grown to some extent or more on every continent except Antarctica.

(Ranhotra,1999)

Wheat has the widest adaptation of all cereal crops and is grown in some 100 countries

around the globe as far as Finland in North and Argentina in South.(Oleson, 1999).

From the sea level to 5000 m altitude. Wheat is grown in altitude ranging from sea level

to 3050m in Kenya and 4572 m in Tibet.(Kent, 1983).

In Nepal the altitude of wheat cultivation now varies from about 70m in the Terai to high

as 4000 m in the hills.

In areas where rainfall ranges between 30-113 cm. The total consumptive water

requirements for wheat crop are about 300 mm.

The world record yield of wheat is 14-15 tons/ha reported from USA and China.


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Bread wheat (Triticum aestivum) covers about 90% of the world wheat area and only 9%

coverage by Durum wheat (Triticum-durum) sometimes called Marconi wheat.(Joshi and

Regmi, 1988).

The optimum growing temperature is about 250C with minimum and maximum growth

temperatures of 30to 40C and 300to 320C (Curtis, 2002).

Nepal exported Rs. 240 million worth of wheat flour to Tibet in 1996/97 (25 years of

wheat research in Nepal, 1997).

In general, recommended seed rate for normal sowing of small grains is 100 kg/ha, 120

kg/ha for normal sowing of bold grains and late sowing of medium grains while 130

kg/ha is recommended for late sowing of bold grains.

The line to line spacing of 20-25 cm or for normal sowing with hoe and 17-20 cm for late

sowing or normal sowing with seed drill.

The recommended depth of sowing is 5-6 cm.

Generally, broadcasting and dropping the seeds behind the plow are the most common

methods of wheat sowing. Line sowing is limited to few progressive farmers while seed-

drill (tractor or bullock drawn) is practiced by some farmers in Terai.

The general recommendation of fertilizer use is 80:40:20 kg/ha for irrigated conditions

and that for rainfed conditions as 40:40:20 kg/ha. A half a dose of N and a full dose of

P2O5and K2O are applied as basal dose for irrigated wheat but all doses is recommended

as basal dose for rainfed condition.(Joshi and Regmi, 1988).

November 19th sowing of wheat produced the highest average grain yield and planting

early or after November 19 reduces the grain yield. NARC (Annual Report, 1997/98).

The trend of wheat farmers of sowing wheat is around 15 thNov. which seems to be in

right direction.(NARC Annual Report, 1988/89).

More than 85% i.e. 567000 ha of wheat grown in the country follows rice.

The per capita wheat consumption has increased from 17.4 kg in 1972 (the year with

birth of the NWRP) to 54 kg in 2002.(NARC Annual Report, 2001/2002).


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Table 1. Released Wheat Cultivars in Nepal

S.

N.

Variety Year of

release

Origin Yield

Potential

Mt/ha

Maturit

y

Recommendation Domain

1. Vijaya 2011 4.45 111-123 Terai, Tars and Lower

Valleys up to 500 masl.

2. Aditya 2010 Nepal 4.8 118 Terai, Tars and Lower


3. Nepal 971 2010 Mexico 4.5 122 Terai, Tars and Lower


4. WK 1204 2007 Mexico 6.89 160-170 Mid and High Hills

5. Gautam 2004 Nepal 5.0 105-115 Irrigated, both normal and

late sown condition of

whole Terai, Tar and foot-

hills(


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11. BL-1135 1994 Nepal 5.0 115 Terai

12. Annapurna-4 1994 CIMMYT 5.0 161 Hilly Region

13. Bhrikuti 1994 CIMMYT 5.0 120 Terai (Early and Late

sowing)

14. BL-1022 1991 Nepal 5.0 120 Western Terai From

Narayani river)

15. Annapurna-3 1991 CIMMYT 5.5 165 Hilly areas

16. Annapurna-2 1988 India 5.0 161 Mid Hill

17. Annapurna-1 1988 CIMMYT 5.5 168 Hilly areas

18. Nepal-251 1988 India 5.0 118 Terai

19. Nepal-297 1985 India 5.0 117 Terai (Late sowing)

20. Vaskar 1983 Mexico 5.0 125 Mid-Western Terai

21. Binayak 1983 India 4.0 120 Terai (Late sowing)

22. Siddhartha 1983 India 4.5 118 Terai

23. Triveni 1982 India 4.0 124 Terai

24. Lumbini 1981 India 4.0 120 Terai

25. UP-262 1978 India 4.0 122 Terai

26. HD-1982 1975 India 5.0 120 Western Terai

27. NL-30 1975 India 4.0 120 Western Terai

28. RR-21 1970 CIMMYT 4.0 116-160 Terai, Hill

29. S-331 1968 India 4.5 122 Mid Hill, Terai


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Fungal diseases Wheat rusts, smuts, bunts, mildews, molds etc.

Bacterial diseases Bacterial blights, spots, scabs

Nematodal diseases Root knot and cyst, cockle, ergot

Viral diseases BYDV, wheat streak virus

Globally, 128 different diseases are recorded to attack the wheat crop (CPC, 2007) and in Nepal

there are 26 different wheat diseases including both minor and major diseases (Mahto et al.and

etal, 2010). However the major and important diseases of Nepalese wheat are illustrated below.

Table 2. List of Wheat Rusts Disease recorded in Nepal and their distribution.

Source:

Annual Report

1987/88

NARSC and

http://www.do

cstoc.com/doc

s/71699988/Li

st-of-Wheat-

Diseases-

recorded-in-

Nepal

Wheat

Rusts

Diseases

Wheat rust

pathogens

belong to

genus Puccinia, family Pucciniaceae, order Uredinales and class Basidiomycetes . (Singh et

al.and etal, 2002) Rust pathogens are the fungal pathogens. Temperature as well as humidity is

regarded as the important climatic factors affecting the establishment and further growth of rust

pathogens. In addition, a free film of water on the host surface influences urediospores

S.N. Name of

disease

Causal

organism

Year Reference Prevalence Status

1. Brown rust Puccinia

recondita

f.sp.tritici

1980s AnnR,PP

D

1988

Widespread

Tari

Major disease

of Terai and

valley areas

2. Yellow

rust

P. striformis

f.sp.tritici

1988 Proceedin

g

1992

Widespread

Hills

Major

3 Stem rust P. graminis

f.sp. tritici

1989 AnnR,

NWRP

Terai &

hills

Minor disease

of some local

wheats in the

hills


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germination, production and penetration by fungal hyphae. Temperature apparently is a major

deciding factor in the development spread of wheat rusts in the Indian sub-continentSouth Asia

.(Joshi, 1986).

In wheat there are three different forms of rust disease

Yellow Rust

Leaf Rust

Stem Rust

Leaf Rust (Brown Rust)

Nepali Name:Khairo Sindure

C.O.:Puccinia recondita Tritici reconditaRob. Ex Desm.

More than 150 physiologic races are known.(Shurtleff and etalet al., 1978).

Distribution:The disease is found wherever temperate cereals are grown. (Prescott and etalet

al., 1986). The disease is distributed throughout Terai, inner Terai, Tars and lower elevations

(below 2500 meters). Hot spot locations of leaf rust are Tarahara, Kankai, Rampur, and

Khairenitar.(Joshi and Regmi, 1988).

Hosts:Leaf rust can affect wheat, triticale and many other related grasses.

Primary hosts: Bread and durum wheat, triticale (Singh and etalet al., 2002).

Alternate hosts: Meadow rue, Thalictrum sp. Species of Anchusa, Anemonella and Isopyrum

Weak parasite on certain cultivars of barley, AegilopsandAgropyron species.(Joshi and Regmi,

1988).

Symptoms: The pustules are circular or slightly elliptical, smaller than those of stem rust,

usually do not coalesce, and contain masses of orange to orange-brown urediospores. Infection

sites primarily are found on the upper surfaces of leaves and leaf sheaths, and occasionally on the

neck and awns.(Prescott and etalet al., 1986).


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Small (up to 1.5mm), round to oval, raised, orange-red, dusty pustules or sori are scattered or

clustered on the leaves and leaf sheaths of susceptible wheat varieties. Each pustule contains

thousands of microscopic orange red urediospores. Rust usually starts on the lower leaves and

gradually progresses up the plant to the flag leaf. A circle of small pustules may ring large, older

pustules.( Shurtleff and etalet al., 1978).

The uredia formed are bigger in size than the uredia of yellow rust fungus. When old the uredia

of leaf rust cannot be generally distinguished by color from those of the yellow rust except for

their irregular arrangements. Heavy rusting of the foliage results in poorly developed root

system, poor quality and quantity of grains and reduced yield of straw.(Singh, 2009).

Development: Primary infections usually are light and develop from wind-borne urediospores

that may have travelled long distances. The disease can develop rapidly when free moisture is

available and temperatures are near 20C. Successive generations of urediospores can be

produced every 10-14 days if conditions are favorable. As plants mature or when environmental

conditions are not favorable, masses of black teliospores may become evident (Prescott and

etalet al., 1986).

LR is likely to appear in epidemic form where the weather, during crop growing season is mild

and moist. LR develops rapidly between 15 and 220C when moisture is not limiting. Late

plantings are more likely to favor the disease development.(Joshi and Regmi, 1988).

Leaf rust develops rapidly at temperatures between 100 and 300C and . in highly susceptible

genotypes, florets, tillers and plants can be killed by early epidemics.(Singh and etalet al., 2002).

Importance: Severe early infections can cause significant yield losses, mainly by reducing the

number of kernels per spike, test weights, and kernel quality.(Prescott et al.,and etal 1986). In

sever attack the plants mature early produce light and shriveled grains.(Saha, 2002).

Stem Rust (Black Rust)

Nepali Name:Kalo Sindure

C.O.:Puccinia graminis tritici(Eriksa. And Henn, ????).


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There are more than 340 physiologic races of the wheat attacking variety tritici.(Shurtleff and

etalet al., 1978).

Distribution: Stem rust is found wherever temperate cereals are grown. In Nepal it occurs

throughout Terai on a moderate scale. But but it isnot a major problem in Nepal.the country

(Joshi and Regmi, 1988).

Hosts:Stem rust can affect wheat, barley, triticale, and many other related

Primary hosts: Durum and bread wheats, barley, triticale (Singh and etalet al., 2002).

Alternate hosts: Barberries (Berberis vulgaris, Berberis Canadensis, Berberis fendleri - (chutro

in Nepali)) and certain species of Mahonia. Certain barley , rye and oat cultivars and some

grasses (wild barley and Aegilops sp. ) are also parasitized and may be sources of primary

inoculum. (Joshi and Regmi, 1988).

Symptoms: Pustules (containing masses of urediospores) are dark reddish brown, and may occur

on both sides of the leaves, on the stems, and on the spikes. With light infections the pustules are

usually separate and scattered, but with heavy infections they may coalesce. Prior to pustule

formation, "flecks" may appear. Before the spore masses break through the epidermis, the

infection sites feel rough to the touch; as the spore masses break through, the surface tissues take

on a ragged and torn appearance.(Prescott and etalet al., 1986).

The elongated in shape, uredial pustules are more on stem and less on leaves and ears so also

named as stem rust. Black rust is called the killer of the wheat plants and in severe infection

there is shriveling of grains and failure of crop.(Saha, 2002).

Soon after the pustules appear, they rupture the epidermis exposing a reddish brown powdery

mass of urediospores. A single pustule may produce 350,000 thousand spores. The pustules and

the fragments of epidermis that adhere to the sides and ends of the pustules gives them a ragged

appearance and are the characteristics that distinguish stem rust from leaf rust .(Shurtleff and

etalet al., 1978).

Formatted:Font: Italic


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Penetration 15 29 35 High Essential

Growth 5 30 40 High None

Sporulation 15 30 40 High None

Yellow Rust

Germination 0 9-13 23 Low Essential

Penetration 2 9-13 23 Low Essential

Growth 3 12-15 20 High None

Sporulation 5 12-15 20 High None

Source: Singh and etalet al.(2002)

Stripe Rust (Yellow Rust)

Stripe rust or yellow rust is principally a disease of wheat grown in cooler climates (20 to 150C)

which are generally associated with higher elevations, northern latitudes or cooler years.(Singh

and etalet al., 2002).

Nepali Name:Pahelo Sindure

C.O.:PucciniastriformisWest

Distribution: The disease is found in all highland and/or temperate areas where cereals aregrown.(Prescott and etalet al., 1986).It is a serious disease of high and mid-hills of Nepal above

4000 ft.. Hot spot locations are Kavre, Jumla, Marpha, Pakhribasm, Lumle. Occurring in

epidemic form since 1985.(Joshi and Regmi, 1988).

Host:Stripe rust can attack wheat, barley, triticale, and many other related grasses.(Prescott and

etalet al., 1986).Have wider host range infecting rye and over 18 genera of grasses including

barley that serve as reservoirs for the fungus.(Joshi and Regmi, 1988).

Primary hosts: Bread and durum wheat , triticale, a few barley cultivars(Singh and etalet al.,

2002).

Alternate hosts: Unknown(Singh and etalet al., 2002)


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Wheat inoculated with aeciospores from B. Chinensisresulted in uredinia, which demonstrated

that Berberis spp. also serve as alternate hosts for the wheat strip rust pathogen. And hence the

sexual recombination has likely played an active role in contributing to pathogen variability.(Jin

and etalet al., 2010).

Symptoms:The pustules of stripe rust, which. Contain yellow to orange-yellow urediospores,

usually form narrow stripes on the leaves. Pustules also can be found on leaf sheaths, necks, and

glumes.(Prescott and etalet al., 1986).

Uredo pustules of the disease occur on the leaves but in severe attack they are formed on the leaf

sheaths, stalks and glumes too. The arrangement of lemon yellow pustules in rows is the

characteristic feature of yellow rust. Hence, named also as stripe rust. In severely attacked field

the ground or field may appear orange or red due to a large number of spores falling on it.(Saha,

2002).

While the telia appears late as dull black patches or spots chiefly on the under surface of the leaf.

Like uredia they are often arranged in rows. They do not break through the epidermis and remain

covered by the epidermis as a flat black crust.

Plants attacked by YR generally show a poorly developed root system. This seems to be the

result of heavy leaf infection which hinders the translocation of carbohydrates from the leaves to

the roots which are starved.(Singh, 2009).

Development: Primary infections are caused by wind-borne urediospores that may have

travelled long distances. The disease may develop rapidly when free moisture (rain or dew)

occurs and temperatures range between 10-20C. At temperatures above 25C, the production of

urediospores is reduced or ceases and black teliospores are often produced.(Prescott and etalet

al., 1986)

Epidemiological studies indicated that the favorable time for YR development in Kathmandu

valley is between December and March. It was also found that temperatures of 5-150C with

abundant moisture were congenial conditions for the epidemic development of YR. LR howeverstarted appearing early in October and remained developing until June.( NARSC Annual Report,

1987/88).


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Importance:Severe infections can cause yield losses, mainly by reducing the number of kernels

per spike, test weights, and kernel quality.(Prescott and etalet al., 1986).When infection occurs

early in the season followed by a long period of cool weather, a severe epidemic may develop

with heavy losses in yield.(Joshi and Regmi, 1988).

Statement of the Problem

Wheat is the third most important crop in Nepal in terms of production and area but still occupies

the second most value in terms of food utility. Wheat is prone to numerous diseases in the world

context but only few several diseases attack Nepalese wheat. Rust disease on wheat has been one

of the major constraints of wheat production in Nepal. Each year about 20% of the wheat that

otherwise would be available for food and feed is lost to disease.(Joshi and Regmi, 1988).All

together 34 wheat cultivars have been released since organized wheat research started in the

country. However, only 22 varieties are in cultivation whereas 12 varieties have been denotified

since their resistance to major disease broken out and regarded as degenerated.( Tripathi and

etalet al., 2012). For this the wheat varieties/genotypes has to be tested against the disease

resistance and their validity to be still able to be grown or needs to be abandoned. The changing

climate scenario and diverse micro climatic environments in the country have possessed new

challenges like Yellow and leaf rusts, stem rust, Spot blotch, etc. in wheat production.(Tripathi

and etalet al., 2012). There is emergence of serious issues that were not present previously in

wheat production like climate change effects, resurgence of super races of disease such as stem

rust race Ug99, major yield losses caused by yellow rust in several countries.(Joshi and etalet

al., 2012). Hence preparations against the wheat diseases specially rust and information on their

occurrence, distribution becomes inevitable research and survey aspects for future wheat

progress.

Objectives

The study was undertaken with the purpose of following objectives


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General objective

To scrutinize upon the wheat rust disease status to the date today and gather the

guidelines important for the wheat growers/farmers (about the better varietal knowledge

against rust control and management) and research entities (on the mode and pace of

direction of the wheat rust disease research in progress for Nepal and drive the wheat

agriculture to boost productivity and production uplifting the national food basket and the

economy of the farmers through rust resistance varieties identification, selection and

distribution.

Specific objectives

To evaluate the 45 different wheat genotypes/varieties against the three wheat rusts viz.,

Yellow rust, Leaf rust and Stem rust for their resistance.

And hence to segregate/identify out the better wheat genotypes/lines from the worst and

the poor against the rust resistance.

To monitor the wheat rusts disease in the farmers field and access rust prevalence and

their severity.

Justification of the Study

The evaluation and monitoring of the wheat rusts is prompted in order for the knowledge up -

scaling and updating with respect to the wheat rust disease in Nepal. It is of sure importance as

rusts disease of the frequent outbreaks of epidemics and considerable losses to the wheat

production has been encountered often in the country. The study will definitely provide the

comparative analyses and conclusions on the wheat genotypes for their excellence against the

wheat rust disease in Nepal. Monitoring of farmers field for wheat rusts on one part of the study

provides the rust scenario in connection to their incidence, severity, distribution and economic

significance while the other section of the study with wheat genotypes/varieties that are released

and on the pipeline to be released being evaluated will promote the selection and distribution of

the only rust disease outsmarting wheat varieties among the wheat growing farmers and at the

same time also would guide or provide the wheat research bodies like NARC with the evidences

and information on how the research works of wheat against the rust disease is heading towardsand forecast the future of the wheat progress in terms of disease resistance and increase in

production and productivity.

Formatted:Justified


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Scope of the Study

The study was mainly undertaken to assist the Wheat research program undertaken in at the

NARC in relation to wheat varieties released and to be released to assess their performance and

liability against the wheat rusts. However the study encompasses some more scopes with it with

its nature of outcomes as predictable.

Nepal Agricultural Research Council can make the conclusion on the varietal research

work of wheat against rust resistance.

The study will provide the guidelines for the wheat researchers for what is the situation

and what needs to be done in wheat varietal development for rust resistance.

The evaluation of wheat genotypes will certainly aid the NARC as well as other research

bodies to identify or segregate the better lines of wheat against rust resistance and carry

the selection, multiplication and dissemination of seeds of the rust outsmarting wheat

cultivars.

The study will provide the rust disease situation in farmers field at Bhaktapur district and

aims to assist the agricultural organization in supply and distribution of rust control or

management tools like resistant cultivars.

The study prompts to upscale and update the information on wheat rust disease among

the farmers and concerned agricultural units.

With the final output of the study, it facilitates farmers and wheat growers of Nepal with

guidelines on which varieties to be selected best against wheat rusts disease resistance,

better disease control and management.


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The paper is also supposed to be useful for the academic purpose mainly for the

agricultural students, teachers, trainers etc.

Major Assumptions

Research Funding will be available and released timely.

Climatic factors will remain favorable throughout the project period

Political environment will pose no hindrances to the research procedures and schedules

The setup of experiment will give the consistent result

Research co-coordinator and collaborative organization will be in active touch and

participation


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LITERATURE REVIEW

Wheat Rusts in Nepal

Available literature point that Theat least three rust types of wheat have been the cause of

significant loss in wheat production in Nepal. Yellow rust has been of greater concern due to

frequent epidemics with recent ones during 2004, 2005, and 2007 with losses up to 50% since

the commonly identified pathotypes were virulent on widely grown wheat cultivars RR21,

Annapurna-1, Annapurna-4, and Nepal 297. Stem rust occurs very late when the normal wheat is

harvested. Leaf rust though important in Nepal, has been managed through incorporation and

pyramiding of resistant genes like Lr34/Yr18, Lr46/Yr29 and other slow rusting genes. In last

few years seven wheat varieties including those resistant to stem rust race Ug99 are released. Thecultivars are Gautam, WK 1204, Aditya, NL 971, BL 3063(Vijay), BL 3235) (Gaura) and BL

3503 (Dhaulagiri). In addition, two Ug99 resistant varieties viz., Francolin (NL 1073) and

Danphe#1 (NL 1064) are in pipelines as identified for release. These varieties are currently

occupying around 70% of wheat area in Nepal.(Sharma and etalet al., 2012).

Leaf rust is most widespread and regularly occurring disease throughout plain area, river basin

(


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Pasang Lhamu is has been observed with low or yellow rust free since about 15 years. Same is

the case for the Gautam variety in the low hills and river basin areas. Also recently

recommended varieties BL 3503 (Dhaulagiri) and BL 3235 (Gaura) has lower or no disease

infection. Stem rust causes yield losses up to 70% in Nepal.

Leaf rust highly infected the popular variety RR 21 in 2036/37 which led to necessity of the

alternative varieties. Then different varieties like Nepal 297, Siddhartha, Achyut, Rohini,

Bhrikuti and others too at different period had been recommended. Later, leaf rust was found

severely in varieties like Nepal 251 and Nepal 297.(Sharma, 2012).

All together 34 wheat cultivars have been released since organized wheat research started in the

country. However, only 22 varieties are in cultivation whereas 12 varieties have been denotified

since their resistance to major disease broken out and regarded as degenerated. Recently, Vijay

(BL 3063) variety was released in 2010 for all over Terai region, the first variety resistant against

Ug99 race of black/stem rust. Two yellow rust resistant varieties have been released in year 2012

namely Gaura (BL 3235) and Dhaulagiri (BL 3503) for the hilly region. National Wheat

Research Program has also identified other two Ug99 resistant genotypes viz. NL 1064 (Danphe)

and NL 1073 (Francolin) for hills and Terai respectively. Other genotypes like BL 3623, BL

3555 and several others were also evaluated and promoted in pipelines for different ecological

zones.( Tripathi and etalet al., 2012).

Yellow rust has been appearing in Nepal in epidemic form causing huge losses to wheat farms in

the hills. Susceptible varieties Nepal 297 and RR 21 are still grown in farmers field in wider

area resulting in occurrence of new virulent races. In hills there is less genetic diversity and

varietal replacement is slow causing frequent epidemic of rust during favorable condition and

also due to appearance of virulent race. During the epidemic of 2005, 2005 and 2006 the farmers

were forced to abandon the crop when disease appeared in seedling stage. The varieties BL 1064,

NL 1073, BL 2879, and NL 1050 are Ug99 and yellow rust resistant farmer preferred genotypes.

(Sharma, 2011).

The unavailability of the short duration yellow rust resistant variety is reported as constraint forwheat cultivation. Most of the farmers grew RR 21, Pasang Lhamu, Nepal 297, BL 1473 and


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to the yellow rust. Also, Danphe (NL 1064) and Francolin (NL 1073) showed moderately

resistant reactions to the yellow rust.(PPD Annual Report, 2010).

Leaf rust caused by Puccinia triticina is one of the major diseases of wheat in Nepal especially

in Terai region. Time to time leaf rust posed a serious threat to wheat cultivation rendering most

of the wheat cultivars (RR 21, UP 262, Nepal 297, Nepal 251, Vinayak, Sidhartha, BL 1022, BL

1135) susceptible with varying degrees of severity. Leaf rust pathogens (Puccinia triticina)

survive in self-sown wheat plants in the hills of Nepal. Central Nepal serves as a focal point of

leaf rust for further infection and spread in gangetic plain of India (Mahto and Karn, 2010).

A devastating black/stem rust disease of wheat caused by new race TTSK named as Ug99

emerged from Uganda and Kenya is appearing to be approaching to South Asia and posing the

serious threat to Nepal too. Hence, the development of improved cultivars with resistance against

rusts is an important task to combat the future rust epidemics potentialities and increase

production and productivity. ABD (agriculture botany division), NARC has developed many

improved varieties like WK 1204 a high yielding yellow rust resistant for mid and high hills of

Nepal. And other promising genotypes at ABD and NWRP, Bhairahawa for irrigated mid hill

condition are WK 1627, Danphe#1, Danphe#2, Munal#1, Becard#1 and for rainfed condition of

mid hills are WK1481, Chonte#1, Kiskadee#1, Chewink#1 and Chyakhura#1 while Wk936, WK

1481, WK 1803, WK 1776, WK 1723 and WK 1905 are for high hills.(ABD Annual Report,

2010/11).

The disease score for yellow rust was 20R for BL 3467 and 30R for WK 1733. But the score for

Leaf rust was zero for all the entries in the trial conducted .(NARC Annual Research Report,

2010/11).

Nepal faced periodic epidemics in the past due to heavy outbreak of yellow rust disease. The

disease was most prevalent during seventies, when local land races were extensively cultivated.

With Sonalika (RR21) farmers became relieved to yellow rust but after few years it became

vulnerable and new resistant varieties like Annapurna 1,3,4, Kanti and Pasang Lhamu were

released and around 1997 all these varieties except Pasang Lhamu lost their resistance. Thencultivars like Nepal 297 and BL 1473 got popular. But between the 2003-2006 the hill farmers of


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Nepal faced another epidemic of yellow rust knocking down Nepal 297 and RR21 and yield

losses was recorded up to 54 percent in BL1473. (ABD Annual Report, 2009/10).

According to Pokharel (2009) Leaf rust was observed at more severe rate,which was from traces

to70S. Leaf rust was more severe at Dhulikhel and Banepa and comparatively less in Panauti.

The severity of yellow rust was also much ranging from 0 to 60S.

Similarly, Leaf rust and yellow rust are important wheat diseases in context of Nepal. In a survey

at Kathmandu valley, Leaf rust was higher at Bhaktapur and Kathmandu and the severity was

40S and yellow rust was observed 70S at several locations of Kathmandu valley while stem rust

was observed only at Ramkot at later stage on the variety WK 1505 with score of 70S. Also

under the poly house condition at Khumaltar leaf rust was observed on several varieties of wheat

and scored up to 50S on variety WK 1803 and yellow rust was observed and scored 90S on WK

2007 and WK 1714 mentions Bhusal (2009).

Leaf rust is the second major disease in Terai and also increasing in valleys and lower hills.

Yellow rust has been found serious in hills since last several years. Stem rust has been found

sporadic in Nepal. Grain yield losses of 554,30, and 27 percent were recorded due to yellow rust

in Nepal 297, Sonalika, and BL 1473 respectively. Likewise yield losses of 11.5%, 36.3%,

36.9% and 61.3% were recorded due to leaf rust.( NARC-Research Highlights, 2008).

Wheat disease monitoring in various agro-ecological zones in the western hills of Nepal revealedthat yellow rust outbreak was found increasing during 1997 and 1998. The wheat genotypes

namely Annapurna 1, Seri 82, and Pak 81 with Yr9 gene were experienced moderately

susceptible with yellow rust scores of 60MS, 60MS and 40MS respectively.

Field screening, disease progression study and seedling test revealed that NL 810, WK 810, WK

823, NL 731 and NL 769 were resistant to moderately susceptible to yellow rust with slow

development of disease. The genotypes NL776, BL 1473, BL 1530, WK 810 and Pasang Lhamu

were resistant with low yellow rust severity at the mid hill region of Lumle Agricultural

Research Centre(ARC)

Severe outbreak of yellow rust was observed on the river basin area of Baglung, Parbat and

Myagdi districts during 1998. At Kkudule of Baglung and Pakuwa of Parbat yellow rust severity


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ranging from 40MS-S to 60MS-S was noted in variety Annapurna-4 and in BL1022 severity was

high with 80S at Pakuwa. At chambas yellow rust in the variety Morocco was recorded with

100S. The variety Rohini had no rust infection at low hill river basin and WK 685 and BL 1473

were found to be rust free in mid hill domain .(Advances in Agricultural Research in Nepal,

2001).

Monitoring of the wheat diseases exhibited that leaf rust incidence was up to 100S in few areas

of Nepalgunj and Surkhet with susceptible cultivars, 60S in Agra Local at Parwanipur, 100S in

Morocco and 80S in Agra Local at Rampur and 40S in Morocco in Bhairahawa. Leaf rust

occurrence was observed more in western Terai than in eastern Terai. Bhrikuti had high severity

of leaf rust at Manohari, Makwanpur district. Same was with yellow rust with the disease being

recorded more in western hills than in eastern hills with observation records at Amiri, Dang

district.

In Nepal Disease Screening Nursery (NDN), in total of 617 entries of wheat lines tested 228

were resistant to both leaf and yellow rust. In addition 393 and 295 entries were resistant to leaf

rust and yellow rust respectively. Latest cultivar BL 1887, BL 1813, NL792 had low leaf rust .(

NARC Annual Report, 2001/2002).

Survey and monitoring of wheat diseases over 150 sites of 24 districts of Nepal revealed that

varieties RR 21, Nepal 251 and Nepal 297 were found infected with leaf rust in many of the

surveyed areas. Also yellow rust was noticed in many of the hill districts locations with as high

as 100S on varieties like BL 1022, Vinayak and Annapurna-4 at Sipaghat of Kavrepalanchowk

district. The then released varieties Kanti and Annapurna-1 were also found to be susceptible at

Sipaghat and ARS, Kavbre. Also interestingly, yellow rust was also observed in some parts of

Terai in the districts Dang and Banke with high severities.

Due to dry weather the incidence of Yellow rust and leaf rust were low. But Annapurna 1 had

30S-MS, Sonalika had 20S and Bhrikuti 10MS LR while varieties with Yr 9 background showed

yellow rust of 50-60S.( NARC Annual Report, 1998/99).

Leaf rust severity was low and appeared late in the season. Stripe rust severity in the hills was

observed high, Sonalika scored up to 90S, whereas Annapurna -1 showed 80S severity.


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Monitoring of wheat disease in 153 sites of 39 districts of Nepal indicated the presence of Leaf

rust 54% after HLB and YR occupied 4thrank with 32% with loose smut being third.(NARC

Annual Report, 1997/98).

Leaf rust or Brown rust was most predominant with Terai 14% yield loss record in Kalyansona

variety. In 1992 there was outbreak of the leaf rust epidemic in the wheat variety Nepal 297 due

to pathotype 77-2, 77-4 and 104-3.

Stripe rust is also observed occasionally in Terai and inner Terai. During FY 1989/90 wheat

season yellow rust epidemic was observed in Kathmandu Valley, Kavbre, some pockets of

Kavrepalanchok and Sindupalchok districts with grain yield losses of 30% and even more. In FY

1990/91 RR21 was found highly susceptible with 80S - 90S in some pockets of Sindhupalchok

district and 40S60S in Dolakha district.

Screening of 315 wheat varieties against yellow rust at Khumaltar by PPD resulted with 132

genotypes resistant, 45 moderately resistant,79 moderately susceptible and 19 susceptible like

varieties Binayak, BL 1135, Nepal 251, SD1982, Lerma 52, Lermarojo 64, UP 262 and NL 297.

(NARC Research Highlights, 1998).

Leaf rust was at epidemic level during 60s and 70s in Nepal but its severity and incidence

decline after the release of series of rust resistant wheat varieties including UP 262. Again, from

1993 onwards the severity and incidence of leaf rust increased in the country heavily infectingthe cultivars like RR 21, Nepal 251 and Nepal 297.

To the date as many as 46 leaf rust resistance genes have been designated and catalogued in the

world.(Karki and Nayar, 1998).

The major diseases of national importance was were leaf rust in the Terai and yellow rust and

leaf rust in the hills after HLB. Results indicate that Nepalese wheat carry Lr1, Lr3, Lr10, Lr13,

Lr14s, Lr16, Lr23, Lr 26 and Lr34 genes for leaf rust resistance and similarly Yr2, Yr2+, Yr7,

Yr9 and Yr18 genes for yellow rust resistance.(25 Years of Wheat Research in Nepal, 1997).

Leaf rust and yellow rust are among the major diseases of national importance. After an interval

of more than two decades, Stem rust was reported in Khumultar. Race 77-2 of LR and 7E150 of


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YR were the most common races while the most frequent resistant genes present Nepalese

Wheat genotypes were Lr 13, Lr 23 and Lr 26 of LR and Yr 2 and Yr 9 of YR.(Devkota, 1996).

YR epidemics have been recorded in Syria, Iran and Pakistan. New pathotypes of YR virulent on

the Veery varieties made appearance in Pakistan in 1994 and a severe epidemic of YR was

experienced in the year 1995. But the YR was not recorded in Veery varieties in Nepal. The

situation means an evolution of the pathogen to overcome the previously resistant Yr 9 gene for

resistance in these Veery cultivars. This makes the most important varieties Annapurna 1 and

Annapurna 3 for hills of Nepal vulnerable.(Saari, 1996).

Leaf rust is the major disease of wheat in the Terai areas as well as in the mid hills and the loss in

grain yield is estimated to be 14 percent with the moderate level of infection and 20 percent

when there is high rust Severity. Until 1992, LR problem was negligible in Nepal expect in old

varieties like RR 21. But during 1992/93 many of the popular cultivars like Nepal 297, Nepal

251, Vinayak and Siddhartha became susceptible to newly developed biotypes of LR races 77

and 12. While wheat varieties such as Vaskar, UP 262 and Triveni remained resistant to new

races.

Stripe rust has been a disease of cool temperature and cause significant yield losses in

susceptible wheat varieties in the hills with loss up to 30 percent been recorded in Kabre station

in YR susceptible cultivar RR21 when infected at flowering stage. The YR has been under

control after the release and dissemination of wheat varieties like Annapurna-1, Annapurna-3

and Annapurna-4 with Yr 9 gene.(Bhatta, 1996).

In a second semi-arid wheat yield trial the highest yielder showed the highest score of leaf rust

with 15MS,S. while in initial evaluation trial for Terai, Tars and Lower Valleys under timely

sown rainfed condition except NL 740 (5 MR MS), BL1556 (30S MS), and checks, none of the

test entries showed LR.(Sah, 1996).

In one of the trial, most of the entries were resistance to LR. In advance varietal trial (late sown-

irrigated) only some of genotypes were susceptible to LR. The leaf rust of as high as 20MS, S

was recorded in one of among many different trials.(Pokharel, 1996).


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Yellow rust and Leaf rust are important diseases in the constraints of wheat production in Nepal.

Several resistant varieties for LR and YR like Annapurna 1, 2, 3, 4, NL 297, BL 1135 etc. were

developed but due to the evolution of new pathotypes some of the resistant varieties for LR were

broken down especially NL 297 and Nepal- 251

YR appeared very late at 3rdweek of February and Agra Local had 10S infection. The maximum

development of rust was found on 1stweek of April and up to 60S-80S. Also later head infection

was noted.

Similarly LR occurred in mid-April and RR21, HD2380 and NL 697 were heavily infected in

CVT. Also LR infected varieties were NL 697, WK 550, BL 149, BL 1649, BL 1650, HP 1748,

Suzhoe, PWL 147, Siddhartha, Nepal 251, and BL 1135.The hill varieties Annapurna 1, 2, 3 are

were free of both forms of LR and YR.(Sharma and etalet al., 1996).)

LR was number one disease in mid-western region of Nepal. In 1995 LR occurrence was noted

at Keware, Mirdi, Rishing Patan, Yampa, Taranagar and Bhoteodar. The severity of the disease

was high in the varieties RR-21, UP-262, Nepal-251 and Nl-297. The variety BL-1135, Bl-1066

and BL-1022 had high disease incidence at one area while low in other places. The variety NL-

539 was found YR and LR free in Keware but BL-1439 was moderately susceptible while NL-

645 was either clean or with trace infection. The variety BL-1066 had rust severity ranging from

low to high and not uniform (20MS-60S). Similarly, BL- 1135 had low rust incidence at many

places. At Rishing Patan LR epidemic appeared in the March where RR 21 had up to 80S rust

infection recorded in farmers field. Rust incidence was comparatively less in Yampaphant. The

variety NL-297had high rust severity while BL-1022 had low severity in boron application trial.

In seed multiplication trial NL-297 had 60MS,S more than in BL-1066 (20MS). The variety BL-

1022 had 0-30 MS rust incidence and NL-297 had 60S at Yampaphant. All recommended and

promising varieties like BL-1135, BL-1022, UP-262 and BL-1066 were heavily rusted in

Taranagar. LR incidence in all location was high in the varieties NL-297, UP-262 and RR-21.

For YR, it appeared very late in 3 rdweek of February at Lumle. The maximum development of

rust was found on April 1

st

week and up to 60S-80S was noted in Agra Local. YR was also foundat Rishing Patan at 3rd week of February where HD-1982 and NL-30 had as high as 60S


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infection. In field visited YR incidence was not found except in Lerma-52 (5MS) was noted at

Keware.(Sharma, 1996).

A survey carried out during 1995 to identity the occurrence, distribution and severity of wheat

disease in the command areas of RARA, Tarahara showed LR prevalent throughout the

command areas.(Adhikari and etalet al., 1996).

Total of 315 entries were tested in Nepal Disease Nursery (NDN). Some of the released cultivars

viz., Annapurna-1, Vaskar, Siddhartha, UP262 were found susceptible (80S) however cultivars

like Annapurna 2, 3, Nepal 251, Nepal 297 and Bhrikuti were found resistant (0-10 MS). The

Agra Local had the highest disease score of 90S.(Karki and Upreti, 1996).

YR was a great threat to the wheat cultivation in several parts of the hills. To control YR a

fungicide Bayleton is advised to farmers. Bayleton was found the most effective in controlling

the rust and produced the highest grain yield of 2140 kg/ha an increase by 210% over water

sprays.

In Nepal Disease Screening nursery (NDN) 230 wheat strains or lines were evaluated for their

disease expressions against major wheat diseases which led to outcome of 101 entries were

observed resistant to both LR and YR, 170 lines to LR and 117 to YR.(NARC Annual Report,

1988/89).

Investigation into wheat diseases with comprehensive surveys made in different parts of the

country showed stem rust was predominant on most of the local wheats during the period.

Epidemiological studies indicated that between December and March is the favorable time for

YR development in Kathmandu valley. It was also found that temperatures of 5-15 0C with

abundant moisture were congenial conditions for the epidemic development of YR. LR however

started appearing early in October and remained developing until June.(NARSC Annual Report,

1987/88).

Leaf rust and yellow rust are the major problems to the wheat cultivation in the plains and the

hills respectively. The yellow rust in general causes 15-20 percent yield loss while leaf rust isless damaging relatively. In the beginning, the yellow rust was noticed in leaf and leaf sheath but

now one can see the spores even on seed and rachis.


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Recommended varieties Annapurna 1 and Annapurna 2 and promising lines such as Nepal 297,

NL 539, NL 410 and NL 464 are resistant to yellow rust. Likewise, the varieties Siddhartha and

up 262 and promising lines like Nepal 297, Nepal 251 and BL 1066 are resistant to Leaf rust .(

Manandhar and etalet al., ..).

Wheat Rusts in South Asia and Some Third Countries

Wheat rust diseases are among the major biological threats to wheat production causing

significant yield and quality losses in almost all wheat growing countries under favorable

conditions. South Asia is not an exception in this regard and one or other rust species is of

serious concern in countries of the region under favorable conditions.(Dusunceli, 2012a).

India: In India rusts are one of the serious wheat diseases. Leaf rust has proved to be most

damaging in Punjab, Uttar Pradesh and West Bengal. The yellow rust is common in Northern

Plains, Uttar Pradesh and Bihar. The annual economic losses due to all rusts have been estimated

to Rs. 6 crores in 1940.(Chavan and Kadam 1985).

Stem rust and leaf rust are prevalent all over the country. Leaf rust is perhaps the more important

of the two. Stripe rust is prevalent only in the cooler parts of the country and in the foot hills of

Himalayas and adjoining plains. In 1971-72 and 1972-73 stripe rust appeared in epidemic form

in Punjab, Haryana and Western Uttar Pradesh causing loss of nearly 0.8 to 1.5 million tones .

(Joshi and etalet al., 1986).

Pakistan: The major diseases of wheat in Pakistan are Yellow or strip rust, brown or leaf rust

and black or stem rust. Losses from rust disease on an average are estimated to be about 2

percent but in years under favorable conditions the value goes up to 10-20 percent. Leaf rust is

the most serious of the three rust diseases. The epidemics of 1976 and 1978 had 50-80 percent

severity on most of the commercial cultivars.( Bhatii and Ilyas, 1986).

Wheat rust as a biotic factor is the major constraint to wheat production. Stem rust is great threat

specially to spring wheat in southern Pakistan. Leaf rust occurs on crop in the late growth stage

in Southern Pakistan while yellow rust is the predominant rust in the Northern Pakistan. Wheat

rust surveillance undertaken by Crop Diseases Research Program in the key wheat growing areas

of the country during March 2012 revealed stem rust to be present in Southern part of the

country but absent in the central and western regions in Pakistan. Of the wheat field surveyed in


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the highlands and west of the Pakistan in late March stem rust incidence of 1.1%, Leaf rust

incidence was 19.3% while yellow rust was recorded as 4.4% (Rehman and etalet al., 2012).

Bangladesh: Leaf rust as one of the disease constraints to wheat production is most important

because of their wide occurrence with varying levels of severity. Stem rust of wheat has been a

historical disease and was last observed in the mid-1980s, whereas yellow rust occurs

occasionally with sporadic infection and is restricted to the northern parts of the country. So far

none of the rusts has reached an epidemic level but large scale damage is not unlikely if a

virulent race is introduced and infection occurs early in the crop season.(Malaker and etalet al.,

2012).

Leaf rust is one of the major diseases occurring in almost all the wheat growing regions with

varying degrees of severity. Preliminary studies have shown that in favorable years the loss may

be as high as 40% whereas in normal crop year, it may be 10-15%. So far leaf rust has not

appeared in epidemic form in Bangladesh. Stem rust has never appeared as a problem except in a

few old varieties which are not in cultivation now. (Ahmed and Meisner, 1996).

Bhutan: The main rust disease is yellow rust and brown rusts with a report of serious outbreak

of yellow rust in late 1980s. The other rust stem rust has not been recorded till date though its

presence cant be completely ruled out particularly in lower elevations.(Tshewang and etalet al.,

2012).

Morocco: The survey carried out in 2011-12 that was relatively dry revealed that 38 and 42% of

the 146 inspected fields of bread wheat were infected by leaf and yellow rusts respectively.

Likewise 39 and 11% of the 70 fields of durum wheat were infected respectively with leaf and

yellow rust. However during rainy season such as 2008-09 for instance, almost all inspected

fields of both bread and durum wheat were infected by leaf rust and 60 and 20% of them

respectively by yellow rust with severity reaching 90S on some fields.(Abdelhamid, 2012).

USA: In USA, stem rust has reduced grain yields by as much as 200 million bushels in a single

year. It also lowers test weight, reduces grain quality and causes shriveled kernels and lodging of

the stems. The losses from the stem rust are not greater because of the extensive use of resistant

varieties that matures early and the removal of the rust spreading barberry. New races of rust are


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completely. Balanced fertilizer application and alteration in planting date is also somewhat

effective control measure for yellow rust control. It is best to plant wheat as possible as in the

month of Kartik that escapes the disease.

In Terai, Vijay variety is found with disease resistant capability and is recommended for this part

of the country. The disease occurs less in the recently recommend varieties Dhaulagiri (BL 3503)

and Gaura (BL 3235). The pipeline varieties like Danphe, Munal, BL 1073 (Francolin), Becard-1

and Chyakura are found promising against the stem rust resistance.

Bhrikuti is still popular as no disease attack is encountered for a long time since after being

released while Gautam in Terai and Low hills is also popular. Varieties NL 971 and Aditya are

found with disease resistant qualities.(Sharma, 2012).

Although some very effective fungicides are available to control the rust, high cost and health

hazards have restricted their uses. Use of the resistant varieties has and will be the only

economical and safer method of rust control.(Karki and Nayar, 1998).

Bayleton was found the most effective fungicide to control the rust and to increase grain yield

and 1000 kernel weight of wheat. Plantvax-20 was also found promising but less effective than

Bayleton. There was increase in 32-43% grain yield over control with the spray of fungicides .

(Upreti and Karki, 1999).

Stem rust has been controlled by the use of resistance combinations and Sr26, Sr31 and Sr36

genes seems to be the most effective single gene resistances worldwide. Leaf rust has been

successfully controlled by combination of Lr13 and Lr34 genes.(Roelfs, 1988).

The objective of cultural methods for rust control is to break the life cycle of the rust usually at a

critical stage such as overwintering or over summering,.. In some areas winter wheat is infected

soon after emergence by spores from nearby infected spring wheat. Volunteer plants, or even late

crops of winter wheat. Delaying planting if it does not causes other problems, may prevent this

early infection. Cultivation to remove volunteer plants from an earlier crop may also reduce the

sources of inoculum. On the other hand in the areas where rust inoculum normally arrives late inthe growing season planting early may allow a crop to mature before rust becomes serious .

(Knott, 1989).


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Materials and Methods

Site of Study

Monitoring site: The monitoring of the Wheat rusts was undertaken in farmers field and various

wheat cultivated areas at Bhaktapur district.

Research/trial location:The trial for evaluating the different wheat genotypes released and those

in the progress to be released in Nepal till the date was taken in Nepal Agricultural Research

Council at Plant Protection Division Block.

Duration of Study:The study was designated to beperformed within the period of six months.

It was worked from December 2012 to June 2013.

Wheat Disease monitoring

Field visits and inspections were made in farmers field in wheat growing areas of the Bhaktapur

district mainly in Dadhikot, Balkot, Gathaghar, Duwakot, Gundu etc. A set of semi-structured

questionnaire derived from the Global rust monitoring form was prepared for the monitoring and

data collection in relation to wheat rusts and cultivation practices. Rust scoring was performed

on the basis of Modified Cobbs Scale.

Wheat Varietal Evaluation Trial

45 different genotypes /varieties that has been released by NARC sinceNARC sincethe period

of organized wheat research started in Nepal and those that are in pipeline werepipeline were

selected as trial key input and planted in the plot size of 2m 1m slightly raised for each of the

varietal test. Each of the wheat variety was sown in the parallel rows counting 4 in total at the

spacing of 25 cm across the 1m side of the plot. All the wheat varieties were put to the linear

layout in the order of the released date. The sowing of the wheat genotypes was done in 4

December 4,2012 (Mangsir 19, 2069 B.S.). The rust scoring was carried out April 16, 2013

(Baishak 3rd, 2070) and evaluated for their rust resistance.

Recording Rusts in the Field

Scoring of stripe, stem and leaf rust intensities in cereals, based uponseverity (percentage of

rust infection on the plants) andfield response (type of disease reaction), have been developed by

Loegering. Severity is recorded as a percentage, according to the modified Cobb scale and the


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study follows the same technique for rust monitoring and evaluation both in the farmers field

and trial. The recording process relies upon visual observations. It is common to use the

intervals: Trace, 5, 10, 20, 40, 60, 100 percent for severity recordings.

Field responseis recorded using the following letters:

0 : No visible infection on plants.

RResistant: visible chlorosis or necrosis,no urediaare present.

MRModerately Resistant;small urediaare present and surroundedbyeither chlorotic or

necrotic areas.

MIntermediate;variable sized urediaare present, some with chlorosis, necrosis, or both.

MSModerately Susceptible;medium sized uredia are present and possibly surrounded by

chlorotic areas.

SSusceptible;large urediaare present, generally with little or no chlorosis and no necrosis.

Severity and field response readings are usually combined.

For example:

tR = Trace severity with a resistant field response.

5MR = 5% severity with a moderately resistant field response.

60S = 60% severity with a susceptible field response.

Source: Rust Scoring Guide, CIMMYT


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Figure A. Map of Research Site, Khumaltar, Lalitpur.


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Figure B. Map of the Wheat Monitoring AT Farmers Field

1. Gundu

2. Changunarayan

3. Dadhikot

4. Balkot

5. Duwakot

6. Gathaghar


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OBSERVATION AND FINDINGS

Table 4. Wheat Rust Monitoring Data at different places in the Farmers Field

Serialno.

Date

Location

Cropstage

Disease

Recording

Incidenceon

Fieldlevel

everyon

infected

plants)

Reaction

Type+

Score

1. 11/05/2013 Gathaghar Late

dough

LR M H 45MS

2. 11/05/2013 Gathaghar Dough LR M L 5S,MS

3. 11/05/2013 Gathaghar Maturity LR H M 30MS

4. 11/05/2013 Gathaghar-15 Dough LR H H 40MS

5. 11/05/2013 Gathaghar Late

dough

LR M M 25MS

6. 10/05/2013 Gundu-7 Dough LR L L 5MS

7. 10/05/2013 Gundu-7 Dough LR L L 5S,MS

8. 10/05/2013 Gundu-6 EarlyDough

LR L L 15MS

9. 10/05/2013 Gundu-6 Late

Dough

LR L L 5MS

10. 10/05/2013 Gundu Dough LR L M 20S,S

11. 10/05/2013 Gundu-6 Maturity LR M M 25MS,S

12. 10/05/2013 Gundu-6 Maturity LR M M 25S,MS

13. 10/05/2013 Gundu Maturity LR H H 40S,MS

14. 9/05/2013 Dadhikot-8 Dough - - - -


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15. 9/05/2013 Dadhikot Maturity - - - -

16. 9/05/2013 Dadhikot-9 Maturity YR M L 5S

17. 9/05/2013 Dadhikot-9 Milk LR H H 50S,Ms

18. 9/05/2013 Dadhikot-8 Dough LR H H 55S,MS

19. 7/05/2013 Dadhikot-8 Dough YR M L 10MS

20. 7/05/2013 Dadhikot-8 Milk LR M L 15MS

21. 7/05/2013 Dadhikot-8 Dough LR

YR

L

H

L

H

5MS

70MS,S

22. 7/05/2013 Dadhikot-8 Milk YR H H 50MS

23. 7/05/2013 Dadhikot-8 Maturity YR M L 5MS

24. 7/05/2013 Dadhikot-8 Dough YR

LR

M

M

H

M

40MS

20MS,S

25. 7/05/2013 Dadhikot-8 Maturity LR

YR

M

M

L

M

5MS,S

30S

26. 7/05/2013 Dadhikot-8 Dough - - - -

27. 7/05/2013 Dadhikot-8 Dough - - - -

28. 11/05/2013 Balkot-8 Dough LR M L 5MS

29. 11/05/2013 Balkot-8 Maturity - - - -

30. 11/05/2013 Balkot-8 Maturity YR M M 25MS

31. 11/05/2013 Balkot-8 Maturity YR L L 15MS


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32. 7/05/2013 Balkot-8 Maturity YR H M 30MS

33. 7/05/2013 Balkot-8 Dough LR H H 50S,MS

34. 7/05/2013 Balkot-8 Dough LR

YR

M

M

L

L

5MS

5MS

35. 7/05/2013 Balkot-8 Milk LR

YR

M

M

L

M

5S

20S

36. 7/05/2013 Balkot-8 Dough LR

YR

L

M

L

H

10S

60S

37. 7/05/2013 Balkot-9 Maturity - - -

38. 6/05/2013 Duwakot Late Milk - - - -

39. 6/05/2013 Duwakot Late Milk LR L L TR

40. 6/05/2013 Duwakot Early

dough

LR L L TR


dough

- - - -


dough

- - - -

43. 08/05/2013 Duwakot Late

dough

LR L L TR

44. 6/05/2013 Duwakot Dough - - - -

45. 08/05/2013 Duwakot-8 Dough - - - -

46. 08/05/2013 Duwakot-7 Maturity - - - -


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46

47. 08/05/2013 Duwakot Dough - - - -

48. 08/05/2013 Duwakot-7 Dough - - - -

49. 29/04/2013 Dadhikot YR H H 100S

50. 29/04/2013 Dadhikot - LR H 70-80S, Late

planting

51. 29/04/2013 Balkkot - YR H 100S

52. 29/04/2013 Balkot - CS

YR

H

H

30-40%

80-100S

53. 29/04/2013 Changunarayan,

Bhaktapur

- FB H 92-95


Bhaktapur

- FB H 75-76


Bhaktapur

- LR L 5-10MS


Bhaktapur

- YR H 60S


Bhaktapur

- LR M 20MS,S


Bhaktapur

- LR H In late planting

there was severe

LR but no or

very little LR in

early planting.

59. 29/04/2013 Kharipati, - LR M 20-30 MS


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57/101


58/101


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34. Mangsir Rice Power till Rainfall 0-2 6 kg NK

35. Mangsir Rice Power till Rainfall

+ Well

0-8 1.5 kg 1.5

kg

NK

36. Mangsir

1/2

Rice Power till Rainfall +

Once @

tillering

3-0 12 kg 30-40

doko

NK

37. Mangsir Rice Power till Rainfall 1-0 10 kg NK

38. Mangsir Rice Power till Rainfall 1-0 10 kg 20 doko NK

39. Mangsir Rice Power till Rainfall 1-0 3 pathi 15-16

doko

NK

40. Mangsir Rice Power till Rainfall 2-8 NK NK NK NK

41. Mangsir Rice Power till Rainfall 1-4 2-4

pathi

1-2 doko NK


doko

NK

43. Mangsir Rice Power till Rainfall 0-4 1 pathi *

44. Mangsir Rice Power till Rainfall+

well

1-4 3 pathi NK

45. Mangsir Rice Power till Rainfall 0-6 2 pathi *

46. Mangsir Rice Power till Rainfall 1-3 10

pathi

20-25

doko

*

47. Mangsir Rice Power till Rainfall 0-5 5 kg *


doko

NK

Note : NK = Not known ? = quantity not known * = No occurrence

YR = Yellow Rust LS = Loose Smut

Area(0-0) first numeric = ropani second numeric = aana


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Table 6. Data on Farmers Details

S.N. Name of Respondent Gender Address Contact no.

1. Kamal Shrestha Male Thimi-11 9841098061

2. Chandra Keshav Shrestha Male Thimi-11 015639217

3. Balkrishna Shrestha Male Balkumari, Thimi -

4. Ishwori Basnet Female Gathaghar -

5. Dharma Krishna Shrestha Male Gathaghar 9841531482

6. Chandra Bahadur khulimuli Male Gundu -

7. Nanu Pancha Female Gundu 9841916371

8. Sanu Kc Female Gundu -9. Laxmi Pancha Female Gundu -

10. Madan Thapa Male Gundu -

11. Jit Bahadur Pancha Male Gundu

12. Jagat Bahadur Pancha Male Gundu -

13. Shree Ram Pancha Male Gundu -

14. Narayan Khaka Male Dadhikot -

15. Laxmi Thapa Female Dadhikot -

16. Chakra Bahadur Thapa Male Dadhikot -

17. Nani Maiya Thapa Female Dadhikot 016632596

18. Sanu Maya Khadka Female Dadhikot -

19. Laxmi lal Shrestha Male Dadhikot 9841909836

20. Ram Krishna Shrestha Male Dadhikot -

21. Subak Roka Male Dadhikot -

22. Shyam Krishna Shrestha Male Dadhikot -

23. Kabita Shrestha Female Dadhikot -

24. Suku Maya Shrestha Female Dadhikot -

25. Nani Maiya Shrestha Female Dadhikot -

26. Dhurba Adhikari Male Dadhikot -

27. Sapana Shrestha Female Dadhikot 9803917006

28. Shova Bhuja Female Balkot 9818981320


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53

Irrigation:2 times (pre-sowing + post sowing)

Weeding:1

Plot size: 2m1m for each genotype

4 rows of seeding (25 cm spacing) along a metre side


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Table 7. Rust Disease Scoring AT Wheat Evaluation Trial 2012/13, Khumaltar

S.N Wheat

Genotype

Growth stage Disease Recordings Remarks

YR LR SR

1. Lerma-52 Late milking 70S,MS - - Drying of plants

2. Lermarojo-64 Late

milking(dry)

20MS,S - -

3. Kalyansona Late milking 80S - - Leaf drying

4. Pitic-62 Mid milking TR - -

5. RR21 90S - -

6. NL 30 90S - - Dried, head drying and

awn infection

7. HD 1982 100S - - Head drying

8. UP 262 90S - - Awn and glume infection

9. Lumbini Late milking 80S - - Awn and glume infection

10. Triveni 20S,MS - - Awn and glume infection

11. Vinayak Mid milking 80S - - Awn and glume infection

12. Siddhartha Milking 20MS -

13. Vaskar Milking 100S - -

14. Nepal 297 Mid milking 90S - - Awn infection and glume

infection

15. Nepal 251 Mid milking 80S - -


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16. Annapurna-1 5-10 MR,

MS

TMS MR

17. Annapurna-2 Early milking 40S, MS - -

18. Annapurna-3 Early milking 30MS, S - -

19. BL 1022 Early milking 10MS,

MR

5S ?

20. BL 1135 Mid milking 90S - -

21. Annapurna-4 90S - - Severe infection including

awn and glume

22. Achyut Early milking 70S - - Awn and glume infection

23. Rohini Mid milking 100S - - Awn and glume infection

24. Kanti TR - -

25. Pasang Lhamu - TR? -

26. BL 1473 Mid milking 50S - - Awn and glume infection

27. Gautam Early milking TR TM

R

-

28. WK 1204 Early milking - TM

R

-

29. Aditya Early milking 10MR - -

30. Vijaya Early milking 100S - - Awn and glume infection

31. NL 971 Mid milking 10MR - -

32. BL 3235 Early milking - 5S, -


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56

MS

33. BL 3503 Mid milking 20MS,MR - -

34. BL 3623 Early milking TR, TMR - -

35. BL 3872 Early milking TMS -

36. NL 1055 Mid milking 80S - - Awn infection

37. NL 1008 Mid milking 10MR, R - - Glume infection

38. NL 1064 Mid milking 20 MR - -

39. NL 1073 Late milking - - -

40. Triticale Early milking - -

41. Durum - - -

42. Becard#1 Mid milking 10 MR - -

43. Chyakhura-1 TMR - -

44. WK 936 Early milking 5S -

45. WK 1481

(mudule)

Mid milking - - -

Note: YR = Yellow Rust LR = Leaf Rust SR = Stem Rust

S = Susceptible MS= Moderately Susceptible MR = Moderately Resistant

TMR = Trace Moderately Resistant TR = Trace Resistant TMS = Trace

Moderately Susceptible R = Resistant

? = May be


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57

RESULT AND DISCUSSIONS

Result on Wheat Rusts Monitoring at Different Locations in Farmers Field.

Wheat rust monitoring was carried out in different locations around the Farmers field (Gundu,

Gathaghar, Balkot, Dadhikot, Duwakot, Kharipati, Changunarayan) with the purpose of

assessing the rusts disease situation in the FY 2012/2013. In total, 66 farmers field sites were

visited during the entire monitoring schedule and results are discussed in the following section.

Among the 66 sites monitored across the different areas with farmers wheat cultivated field, 24

(i.e. 36.36 % of total sample size) sites were observed with the yellow rust disease infection;

with 15 of them having high severity attack, 4 having the medium and 5 fields with low

severities. The level of severity (high, medium and low) for the disease in terms of percentage in

correspondence to total yellow rust attack is found to be 62.5%, 16.67%, 20.83% in respective

order. Also, the incidence level viz., high, medium and low had 13, 10, 1 entries each giving

54.16% , 41.67% and 4.17% share respectively with respect to total number of yellow rust

diseases infection. The disease score was highest with 100S in few areas of Balkot and Dadhikot

of Bhaktapur district.

Table 8. Incidence and Severity Levels of the Yellow rust and Leaf rust disease

Disease Incidence Total

(+)

Severity Total

(+)H M L H M L

Yellow

rust

13 10 1 24 15 4 5 24

% in

total(+)

54.16% 41.67% 4.17% %

total

sample

36.36% 62.5% 16.67% 20.83%

Leaf

rust

6 12 14 32 8 8 16 32

% in

total(+)

18.75% 37.5%% 43.75% %

total

sample

48.48% 25% 25% 50%


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In case of leaf rust 32 of the farmer fields that were monitored was observed with this disease

infection sharing 48.48% of total sample sized. As in the above table, the number of infection

into the high, medium and low severities are calculated to be 8, 8, and 16 respectively sharing

between them 25%, 25%, and 50% in sequential order. While for that of incidence level

categorically high, medium and low it comprised 6, 12, 14 number of infection respectively

sharing 18.75%, 37.5% and 43.75% in respective levels. The disease was recorded highest in

some sites of Dadhikot with 70-80S, 50S,MS and in Balkot with 50S,MS.

Six of the farmers field was found having both the yellow rust and leaf rust to some extent in

varying degrees to each other. However, 16 of the surveyed areas were found free from the rust

disease.

In summary in total of 66 surveyed farmers field 32 of them have leaf rust disease infection

while 24 of them were found with yellow rust disease infection and 6 of them having both leaf

and yellow rust. In other way 48.48% monitored sites have leaf rust, 36.36% have yellow rust

and 24.24% had no rust infection at all. Additionally, yellow rust infections have highest of

percentage falling in high severity and high incidence zone. In contrast leaf rust infections have

highest of the percentage falling in the low severity and medium incidence zone. Over viewing

the disease score table it could be generalized that yellow rust was severe up to 100S mainly in

the Balkot areas while in Dadhikot both of leaf and yellow rust was prevalent from low severity

8%

12%

31%

23%

17%9%

Figure 1. Distribution of the sample size by

location wise

Gathaghar

Gundu

Dadhikot

Balkot

Duwakot

Changunarayan


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59

to high severity variation. Farmersfield around Gundu was observed with low to medium level

of leaf rust majorly. Similarly, in Gathaghar region Leaf rust was common with moderate level

of severity. However the sites monitored in Saraswotikhel-Duwakot were mostly rust free and

healthy except in few fields with very insignificant severity and trace resistant display. Lastly, in

Changunarayan there was little leaf rust with low severity and one of the fields with high yellow

rust(60S).

1

3

5

7

9

11

13 12

11

0 0 0 1

7

5

8

5

3 3

4

2

0 0

8

2YR LR No

Figure 2. Distribution of Wheat Rusts in Farmers Field

Known

25.00%Unknown

64.58%

No Disease

10.42%

Figure 3. Knowledge on farmers about wheatdisease in history

Known

Unknown

No Disease


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60

Discussion on Wheat Rusts Monitoring Results.

Rust disease is found in all highland and/or temperate areas where cereals are grown.(Prescott

and etalet al.1986).)Joshi and etalet al.(1988) mentioned that yellow is a serious disease of high

and mid-hills of Nepal above 4000 ft.. Also, Yellow rust is a major disease which poses a serious

threat in wheat cultivation and occurs mostly on mid and lower hills, river basin and valleys

according to Mahto and Baidya (2012). The observation thus obtained in the process of

monitoring wheat rusts in farmers field at Bhaktapur district which too being geographically

positioned in mid-hill belt with yellow rust disease occurrence ( of 36.36% of total sampled

fields) is easily understandable. Nepal faced periodic epidemics in the past due to heavy outbreak

of yellow rust disease. (ABD-Annual Report, 2009) In Nepal, yellow rust epidemics occurred

during 2004-06. Bhaktapur district along with the Kathmandu valley is one of the 10 yellow rust

disease prone districts in the country.(Sharma and etalet al., 2011b).These previous findings

hence can easily be related out with the findings in this paper of high percentage of yellow rust

infected sample sites observed with high severity and high incidence at field level i.e. more

precisely 62.5% of yellow rust infected sites were found with high disease severity while only

16.67%, 20.83% with medium and low level of severity orderly. Also, for incide

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