System of Rice Intensification: Research Perspective in Nepal

Ram B. KhadkaScientist

Regional Agricultural Research Station, Khajura, Banke, Nepal

Presented at National SRI Network Meeting held at 19th June 2015 at NARI Hall, Lalitpur, Nepal

Outlines

• Introduction• Conceptual frame work• Advantages

Research Perspective : National context

IntroductionThe System of Rice Intensification (SRI) is a “set of

insights and practices that change the management of plants, soil, water and nutrients used in growing irrigated rice.” SRI methods, promote the growth of more productive and robust plants.

More simply: SRI is a package of practices especially developed to improve the productivity of rice.

SRI involves intermittent wetting and drying of paddies as well as specific soil and crop management practices.

It is civil society innovation.

Advantages of SRI? Increases rice yield per drop of

water, per kg of seed and fertilizers.

Tolerant to flooding, lodging and drought.

Suitable for organic production. Resource-conserving technology;

SRI is based on local resources Reduce GHG emissions (64% less

methane and 25% less nitrous oxide compared to conventional).

Reduces arsenic (which is toxic to humans) in rice

Why SRI? Consumption demand

and prices for rice increasing

The shortage of water (climate change)

Shortage of land suited for rice productionAbout 50% farmers have land holding less than 0.5 ha.Farmers and scientist have challenge to develop new alternatives to increase the sustainable productivity, in context of climate change.SRI would be the best alternative.

SRI Research Focus in Nepal

Varietal selection Spacing Age of seedling Water management Adoption and socio-economic study

Institutions involved in research

Nepal Agricultural Research Council Tribhuvan University/Institute of Agriculture

and Animal sciences Department of Agriculture/ District Agriculture

Development Offices I/NGOs Civil society organizations Farmers' groups

Historical Background First SRI trials conducted in 1998 by NARC at Khumaltar  2001: CIMMYT and Appropriate Technology Asia (ATA) began trials at

sites near Kathmandu and at NWRP, Bhairahawa, on-station and on-farm. 2002-2003: Farmer Field Schools in the Sunsari-Morang irrigation project

supported by DFID in the terai. 2005: a series of farmer's field trials started conducted at Morang 2004 – 2005: Program on SRI by PARDYP (People and Resource

Dynamics in Mountain Watersheds of the Hindu Kush-Himalayan Region) sponsored by ICIMOD

2010-11: Farmers' field trials at far-western Nepal under EU/FF Project. 2012: Farmers’ field trials was conducted at Bajhang district proving the

relevance of SRI in high-value aromatic rice landraces 2012-2015: RARS, Khajura and ARS, Dailekh conducting on-station

evaluations of different components of SRI. 2008-2014: Five master's thesis research conducted under Tribhuwan

University, Institute of Agriculture and Animal Sciences, Rampur.

Performance of SRINo promising results obtained from Khumaltar trials in

1999.Significantly higher grain yield and tiller were obtained

in 20х20 cm and young seedling compared to narrower spacing and old seedlings in Khumaltar (Evans and Justice, 2002)

In 2001, on-station and on-farm experiments conducted at RARS, Tarahara showed yield increment up to 8 mt/ha in Manshuli variety in SRI.

More than 2 times increased in yield as compared to conventional in farmer's field trials under the Morang-Sunsari Irrigation project.

Cont….Series of experiments were conducted both on-farm and

on- station at NWRP, Bhairhawa (Bhatta & Tripathi, 2005). Conclusion of Bhairahawa experiments were: There is tremendous potential and scope for

increasing rice yields by SRI. 28-49% yield gain was observed over FP. SRI with closer spacing of 20x20 cm to 30x30 cm

performed better than wider spacing of 40x40 cm. Three rotary weedings followed by hand weeding

found effective in SRI. 10-day-old seedlings give better yield. Two seedlings /hill was slightly better than one

seedling /hill

Cont….

40-50% yield increase in SRI compared of available best practices in the trials conducted by PARDYP, with 75% reduction in seed requirements and 50-75% reduction in water use.

SRI with mechanization gave 55% higher yields than conventional cultivation, with 27% reduction in costs of cultivation in the trials conducted at Morang district (Uprety et al.)

Yield different of SRI with conventional practice at different locations

0

2

4

6

8

10

12SRI yield (t/ha)

Conventional yields (t/ha

Districts/organizations

Ric

e y

ield

(t/

ha

)

Source: Uprety 2008

Weeding Effect

412 farmers in Morang district using SRI methods in monsoon season, 2005

Data show that WEEDINGS can raise yieldAve. SRI yield = 6.3 t/ha, vs. control = 3.1 t/ha

----------- No. of No. of Average Rangeweedings farmers yield of yields 1 32 5.16 (3.6-7.6) 2 366 5.87 (3.5-11.0) 3 14 7.87 (5.85-10.4)

Uperty and Uphoff, 2008

0.0

10.0

20.0

30.0

40.0

50.0

60.0

70.0

<4 t/ha 4.1-6 t/ha 6.1-8 t/ha >8.1 t/ha

Per

cent

age

of fa

rmer

s

Yield category (t/ha)

Yield distribution of rice by SRI method according to number of weedings, 2005.

One Weeding

Two Weeding

Three Weeding

Uprety et al. 2005

Effects of methods of cultivation on farmers’ fields, Kailali, 2010

Method of cultivation

Tillers per hill

Effective tillers per m2 TGW Yield

SRI 35.46a 340.50a 21.55a

7.58a

Conventional 6.20b 146.1b 20.98b 4.01b

LSD 1.44 7.23 0.28 0.14

Dahal and Khadka, 2013

Effects of varieties on SRI in farmer’s field trials, Kailali,June-November, 2010

Varieties Tillers per hill Effective tillers per m2

TGW Yield

Sarju #52 20.63bc 249.7b 25.45a 5.69c

Sunaulo Sugadha 17.50d 212.20c 18.76e 6.00b

Radha #4 18.88cd 212.60c 24.55b 5.025d

Jaya 20.63bc 242.90b 21.01c 5.86bc

Mithila 22.75ab 254.90b 18.00f 5.72c

Sabitri 24.63a 287.5a 19.81d 6.47a

LSD 2.510 12.52 0.49 0.25

SEM 0.87 4.35 0.17 0.08

Khadka and Acharya, 2011

Effect of different methods of crop establishment

Wet DSR DRY DSR Conventional SRI0

1

2

3

4

5

6

7

3.363.73

6.4 6.61

Grain Yield

Straw Yield

Yie

ld (

Mt/

ha

)

Khadka, 2015

Different methods of cultivation

Dhital, et. al. 2015

Effect of varieties in SRI and conventional transplanting at farmers’ field trials, Kailali, 2011

Sunaulo Sugandha

Radha #4 Jaya Sabitri0

1

2

3

4

5

6

7

8

97.8

6.9

8 8.2

SRI Planting

Normal Planting

Khadka & Dahal, 2012, unpublished

Effect of variety and method of cultivation in farmers' fields, Bajhang district

Treatments Hills per m2 Tillersper m2

Grain yield (t ha-1)

Methods of CultivationSRI 16b 305.19 7.60Conventional 37.04a 273.23 4.46F0.05 ** * **

Varieties VarietiesInteraction Effects

SRI×Thapachini 16.00b 358.00a 8.11a

SRI×Khumar-4 16.00b 312.00ab 7.87a

SRI×Hansraj 16.00b 245.60bc 6.81ab

Conv.×Thapachini 35.57 a 318.70a 4.25c

Conv.×Khumar-4 39.00a 286.10abc 4.93bc

Conv.×Hansraj 36.57a 214.90c 4.21c

F0.05 7.7 72.9 *SEm± 1.26 378.8 0.34LSD value * * 2.08

Effect of cultivation practice in promising rice lines in mid hills, Dailekh

VarietiesNormal SRI Normal SRI

Tillers per hill Yield (mt/ha)

NR 10676-B-1-3-3-3 11 12 6.3 7.87

NR 10490-8-9-3-2-1 10 15 6.2 7.07

Khumal-10 8 8 6.49 6.8

Source: Ghimire et al., 2015, unpublished data

Performance of SRI in drought-tolerant varieties

Sukh-3 Radha-4 Sukha-5 Sukha-4 Sukha-1 Sukha-60.00

1.00

2.00

3.00

4.00

5.00

6.00

7.00

8.00

9.00

6.54

7.597.87

6.316.07 5.96

Grain weight (mt/ha)Straw yeild (mt/ha)

Khadka et al., 2015, unpublished

Socio-economic study

A farmers' field survey conducted by RARS, Tarahara team at Dhanusha in 2008-09 showed early and summer paddy SRI average yields to be 8.1 and 5.74 mt/ha, respectively, while under normal practices the early and summer rice yields were 3.45 and 3.70 mt/ha (Bhuje et al. 2010)

Research Constraints

• Institutional commitment• Technical know-how• Lack of advanced equipment for taking data:

chlorophyll meter, leaf area meter, root and shoot physiological study, GHG emission chambers, gas chromatography

• Knowledge and information-sharing• Funding

Future Research Focuses

Water budgeting Heavy metal toxicity Soil microbiota profiling Root and shoot architecture and physiology Social dynamics Greenhouse gas emissions (methane and nitrous

oxide) Mechanization (weeders and transplanting or

marking)

Way forward• Research consortium among different

organizations and researchers may be necessary for improving respective and collective efforts

Thanks