Credit Seminar by:-

Pushpendra Koli

Roll no. 20239

Division of Agricultural Chemicals

Indian Agricultural Research Institute

New Delhi 110 012

Anti - Sprouting Agents Status & Future

What is sprouting?

What is the significance of sprouting?

Which are the crops which need anti-sproutiongagents?

How do they work?

What are the different types of sprouting inhibitors?

We should know !!!

Dormancy is a complex physiological process that is utilized by plants to survive stress conditions such as drought and exposure to cold

- Lang et al. 1987

The process whereby seeds germinate or begin to grow

Sprouting is the practice of soaking, draining and then rinsing seeds at regular intervals until they germinate, or sprout

Dormancy:-

Sprouting :-

Increases in weight loss

Conversion of starch to sugar

Reduced appearance and quality of tuber

Impedes air passage leads to Potato Malformation and

unacceptable for marketing

Surrounding tissue also contain elevated level of toxic

Glycoalkaloid which can not be destroyed even after

cooking

Sprouting cause

Bulb and tuber crops are important vegetables cultivated and consumed in most areas of the world

Onions (Allium cepa L. var. cepa)

Shallots (A. cepa L. var. ascalonicum)

Garlic (A. sativum L.)

Potatoes (Solanum tuberosum L.) and

Yams (Dioscorea spp.)

Crops which required anti-sprouting agents

Any compound which suppress the sprouts or germination of seed, tuber or bulb etc.

Chlorpropham was first introduced over 50 years ago and it has become the dominant sprout suppressant globally

Chlorpropham is the most frequently encountered

residue in potatoes and has been regularly found

Sprouting inhibitors

- Briddon A. et al. 2013

- WPPR/PRC surveys

○DIPN (Diisopropylnaphthalene)

○Maleic hydrazide

○MCPP (Methylchlorophenoxypropionic acid)

○Ethylene

○1,4-DMN (Dimethylnaphthalene )

○3-Decen-2-one

○Spearmint oil (active ingredient R-carvone)

○Caraway oil (active ingredient S-carvone

○Clove oil (active ingredient eugenol)

Alternatives to CIPC

Metabolism and Mode of Action

α,β-unsaturated carbonyl compounds constitute new

chemistry for the suppression of sprouting in potato

tubers

Compounds containing this specific arrangement of

functional groups are biological in origin

Relative toxicity of aliphatic compounds to potato sprouts

Compounds are ranked in order of decreasing efficacy

- N.R. Knowles

Mode of Action

Meristematic tissues are most sensitive to being injured by the α,β-unsaturated carbonyl compounds

Sprouting tubers respond to treatment

Increase in respiration rate

Response reflects injury to the developing sprouts

Cells within sprouts experience a rapid loss of membrane integrity and increased peroxidation of membrane lipids

Oxidative stress

Metabolic pathways responsible for

• Neutralizing reactive oxygen species and

• Controlling cellular redox potential

The loss of membrane function, rapid water loss, and reduced ability to neutralize reactive oxygen species

leads to unabated oxidative stress, cell death and tissue necrosis

Sprouts thus exhibit a “burnt out” appearance

Tuber was exposed to 3N2vapours for 19 h

Sprouts darken by

3 h of exposure with

accompanying loss of

turgidity, starting at the

sprout apex and moving

downward

The progressive

loss in turgidity results in

collapse of tissue by 19 h

- N.R. Knowles

Symptoms of the Toxicity of 3-Nonen-2-one to Sprouts

Chlorpropham :- (Bud Nip, Taterpex)

- PGR and herbicide

- Sprout suppressant

- Inhibit potato sprouting

- Sucker control in tobacco

Mechanism - Interfering cell division

Availability - EC and liquid formulations

[ Isopropyl N-(3-chlorophenyl) carbamate ]

Maleic hydrazide

Synthetic compound which has a plant growth

regulating action

Applied to the growing potato crop

Arrest cell division, but does not limit cell expansion

Note - If it is applied too early during tuber development it will limit tuber size and yield

Only one application per season

Maximum Residue Limit (50 ppm)

Mecoprop

Mecoprop, methylchlorophenoxypropionic acid (MCPP)

Use as herbicide found in many household weed

killers and "weed-and-feed" type lawn fertilizers

It is primarily used to control broadleaf weeds

It is often used in combination with other chemically

related herbicides such as 2,4-D, dicamba, and MCPA.

2-(4-Chloro-2-methylphenoxy)propanoic acid

Acyclic monoterpenes as antisprouting agents for potato tubers

Anti-sprouting agent comprising a mixture of essential oils obtained from aromatic plant which inhibit the growth of tubers

Advantages

1. Low mammalian toxicity

2. Rapidly biodegradable

3. Inexpensive

4. No unpleasant taste and odour

5. In addition to these, control fungal growth

6. Reduce post harvest losses

Sprouts inhibition in potato tubers exposed to aromatic essential oils for 7 days

Treatment Size of potato

(cm)

No. of bud % eyes-

sprouted

Papermint oil 5.3 9.7 68

Japanesemint

oil

5.3 8.3 66

Basil oil 7.3 9.3 74

Artemesia oil 6.0 9.3 80

Eucalyptus oil 6.0 9.3 80

Lemongrass oil 6.0 8.0 54

control 7.0 11.3 81

LSD (5%) 1.9 2.7 34

-Farooqi et al. 2002

S-Carvone as a Natural Potato Sprout Inhibiting, Fungistatic and Bacteriostatic Compound

- Oosterhaven et al.

1995

Extraction

S-Carvone is a common monoterpene found in caraway (carum carvi L.)

Two varieties of sweet potatoes were used

This study has shown that response to ethylene, AVG and 1-MCP is not limited to one variety

Continuous exposure to ethylene (10 µl/L) can be used to suppress growth of sprouts in sweet potato roots at room temperature

It is possible that this might provide a strategy for sprout control in developing countries or during long-distance transport

The Effects of Ethylene, 1-MCP (1-Methylcyclopropene) and AVG (Aminoethoxyvinylglycine) on Sprouting in

Sweet Potato Roots

Sprout length & No. of sprouts per root after

4 weeks in storage at 25 0C

-Cheema et al. 2013

Maleic Hydrazide – Sprout control of Onions during Long-term Cold Storage

Maleic Hydrazide (Royal MH) is a herbicide

with PGR activity

Application to foliage

Stops cell division but not cell expansion

Registered in Canada - as a sprout inhibitor in

onions and potatoes

Weather dependent

Application of the MH-60 sprout inhibitor

Result

In conclusion :– Foliar application is easy to apply,

affordable and effective means of controlling

sprouting and moisture loss during long term cold

storage of a range of popular onion cultivars

- http://www.usask.ca

New Options for Sprout Inhibitors

Essential Oils○ Spearmint Oil

○ Peppermint Oil

○ Rape Oil

○ Methylester

○ Methyl-Jasmonate

○ Artemisia oil

○ Biox-C clove oil

Other compounds

○ Hydrogen Peroxide

○ Irradiation

○ CIPC combinations

○ Naphthalenes

○ Imazethapyr

○ Salicylaldehyde

○ Trans-3-nonen-2-one

Biox-C

Clove oil: a.i. eugenol

Distributed by Pace International,

LLC

Thermal aerosol recommended

Registered in US

“Organic ”

Multiple applications necessary

Effect of Biox on Sprout Lengthcm

\tu

ber

-Kleinkopf, 2003

c

CIPC

Untreated

Sprout Weight after Multiple Applications of Clove Oil

8

Sp

rou

tw

eig

ht(g

/tu

be

r

12

Untreated

Clove oil

6

4

2

0

APRIL MAY

10

7 Month after Harvesting

Clove oil

Untreated

Clove Oil (Biox-C) Results

• Effective for burning off sprouts

• Not a true “sprout inhibitor”

• Reapplication is necessary for long-term

control

• May not be appropriate for short dormancy

varieties

High Energy Radiation

• High-energy linear electron accelerator

• Non-radioactive source, electrically

generated ionizing radiation

• Relatively low dose

• Already used on beef, spices, & some

processed food

• Used for cancer treatment

Days after treatment

Spro

ut

weig

ht

(g t

uber-

1Sprout Growth after 25-100 Gy Treatments

-Kleinkopf, 2003

50 Gy

Control

25 Gy

Cont..

Unsaturated Aliphatic Ketone

Trans-3-nonen-2-one

• Rick and Lisa Knowles, Washington State University

(Patent pending)

• Seed age / dormancy release

• Isolated volatiles from potatoes

• Inhibited emergence in test plots

• Tested sprout inhibition in storage

• Showed long-term sprout inhibition with 2 applications

Spro

ut

length

(cm

/tuber)

Feb Mar Apr May June Jul

Sprout length on Russet Burbank at 7.2°C

-Kleinkopf, 2003

Untreated control

Single application

Double applications

Russet Burbank at 7.2°C & 280 Days after Harvest

Current status of some Sprout suppression

Spearmint oil

Received full UK registration (Biox-M,

MAPP 16021) in 2012

Biox-M is a volatile, oily liquid applied by

contractor, as a hot-fog

Dimethylnapthalene

Registered (1,4-SIGHT™) in USA

Registration in the Netherlands & UK in

2013

It is a volatile, oily liquid and is likely to be

applied by contractor as a hot-fog

3-Decen-2-one It was identified in the University of Washington and commercialised by Amvac

Approved as a food additive and received its US registration as a sprout suppressant (Smart Block™) in February 2013

Cont.

EthyleneIt has been available for a few years and the companies are Restrain and BioFresh

Caraway oil

Available for sprout control of seed crops in the

Netherlands as ‘Talent’

- www.potato.org.uk/cipc

PotatoIndustryCIPCStewardship

UK store Chemical Usage

CIPC 94%

Ethylene 4%

Thiabendazole 1%

Imazalil 1%

- Garthwaite et al. (2010). Pesticide usage survey report 227, FERA

Conclusions

Control of sprouting in storage is heavily dependent on the

use of chemicals mostly chlorpropham is used in the world.

Application of alternative compounds with different modes of

action may supplement CIPC efficacy and prove to be

advantageous for the sprout control industry

These alternative compounds also have some additional

benefits such as antifungal, antibacterial

Novel antisprouting agent comprising acyclic monoterpenes

such as citral, geraniol, citronellol, and citronellal and

conventional carriers also found in new hope