Crop Protection Unit

The Crop Protection Unit comprised of Four scientists (Two Senior Scientists and Two Scientists) and One SSS At present the following scientists and technical officers are in position:

Disciplines Entomology, Plant Pathology and Nematology Major Programs

• Refinement and Validation of management module for soil-borne diseases of groundnut
• Development of management practices for Alternaria leaf blight in groundnut
• Studies on white grub and bruchid beetle and their management in groundnut

Current activities

• Survey for collection and identification of white grub species
• Monitoring of insect pests of groundnut
• Management of bruchid beetles in stored groundnut
• Integrated management of major foliar fungal (Early Leaf Spot, Late Leaf Spot, Rust and leaf blights) and soil-borne diseases (Collar rot and Stem rot) of groundnut through cultural practices, fungicides, botanicals, soil-amendments and bio-control agents
• Screening of groundnut varieties/germplasms /advance breeding lines for resistance to major foliar fungal (Early Leaf Spot, Late Leaf Spot, Rust and leaf blights) and soil-borne diseases (Collar rot and Stem rot) of groundnut.

CROP PROTECTION ACHIEVEMENTS: Major achievements from ICAR-DGR. PLANT PATHOLOGY Soil-borne Diseases

• First report of ‘incidence of Sclerotium rolfsii on groundnut foliage’ was brought in1991.
• Early sowing (June) of groundnut with closed spacing (22.2×7.5/10 cm) reduces the incidence of collar rot, stem rot and bud necrosis.
• Soil application of castor cake @ 500 kg/ha in furrow at the time of sowing reduced incidence of stem rot and collar rot by 50% or above and increased the monetary benefit in comparison to farmers practice.
• Soil application of fresh leaves of Parthenium hystarophorus, Azadirachta indica, Pongamia pinnatta and Sorghum halepense @ 500kg/ha at the time of sowing reduced incidence of stem rot considerably with higher pod yield as compared to control under field condition during rainy season.
• The genotypes, NRCG CS 19, NRCG CS 319, have been identified/registered as resistant source for rolfsii.
• Verticillium lecanii as bio-agent was found effective for foliar and soil borne disease management in groundnut.
• Summer ploughing and soil solarization shown to reduce the incidence of stem rot in groundnut.
• Application of arbuscular mycorrhiza in seed furrow reduces the stem rot and increases the plant growth.
• Bio-agent Trichoderma harzianum isolate T-170, mouldboard plough and soil solarization with transparent polythene sheets were effective for management of stem rot disease.
• Deep summer ploughing with mouldboard plough, then soil application of Trichoderma harzianum @ 4 kg/ha enriched in 250 kg FYM/ha as basal application, then seed treatment with Tebuconazole 1.5 g/kg seed, again soil application of harzianum @ 4 kg/ha enriched in FYM @ 250 kg/ha at 35 and 70 DAS, effectively reduces incidence of soil borne diseases (stem rot, collar rot and dry root rot) and helps in getting higher yield.
• Organic management of groundnut diseases:
• Seed treatment with Trichoderma harzianum @ 10 g/kg of seed with furrow application of harzianum @ 4 kg enriched with FYM 250 kg/ha at sowing followed by foliar application of neem seed kernel extract @ 5% first at 30 and 45 DAS in Tamilnadu, Rajasthan and Andhra Pradesh conditions; foliar application of T.harzianum @ 5 g/lit (2.5 kg/ha) at 30 and 45 DAS for Gujarat conditions.
• Seed treatment with mixture of harzianum and Pseudomonas fluorescens @ 10 g each/kg of seed and combined furrow application of both T.harzianum and P. fluorescens @ 2 kg each enriched with FYM @ 250 kg/ha along with foliar application of mixture of both @ 5 g each/lit (2.5 kg/ha each) at 30 and 45 DAS in Odisha, Maharashtra, Andhra Pradesh and Karnataka conditions.

Foliar fungal Diseases

• A new leaf blight disease caused by Alternaria tenuissima was reported in 1982 in groundnut.
• Studies on aerobiology of leaf spot and rust pathogens shown the existence of diurnal periodicity with peak catches of conidia at dew dry-off in the morning and urediniospores peak catches around noon.
• Early planting (15 days prior to normal sowing) with spacing of 45 x 10 cm and intercropping with red gram or castor or sorghum or pearl millet shown to reduce leaf spots and rust intensity.
• Aqueous leaf extracts of neem and mehandi @ 2% were found effective and economical in controlling leaf spots and rust of groundnut. Neem leaf extracts was also effective to Alternaria
• Outbreak of Alternaria blight was recorded in summer groundnut during 2009. Alternaria alternata was identified as causes of leaf blight in summer groundnut in Saurashtra and leads to high severity, if groundnut is grown in the vicinity of cotton. Identified fungicides Tebuconazole 50% + Trifloxystrobin 25% or Metiram 55% + Pyraclostrobin 5% for the management of Alternaria
• Groundnut is a sodium sensitive crop, which can be grown profitably up to a salinity of 2.0 dS m^-1 and irrigation water salinity (ECiw) of 2.5 dS m^-1 in black clayey soil as at this salinity the severity of foliar diseases were less and the pod yield was maximum.
• Difenaconazole 25EC and Tebuconazole 25.9EC were identified for management leaf spots and rust.
• Stem rot incidence up to 30% was recorded in 2009, 2010, 2011, 2013 and 2014 in Saurashtra region of Gujarat. Rust and ELS were severe in 2013 and 2014, respectively. Late leaf spot was recorded in most of the years with the disease severity of more than 60%.
• Fusarium incarnatum– equiseti species complex –reported as casual agent of leaf blight and wilt disease of groundnut from Western part of Rajasthan.
• Treating seed with mancozeb (2 g/kg of seed) followed by two sprays of hexaconazole @ 0.1% at 45 & 60 DAS, or Treating the seed with Tebuconazole 1.5 g/kg of seed followed by two sprays of Tebuconazole @ 0.1% at 45 & 60 DAS.

Virus Diseases

• Application of dimethoate 30EC reduces the incidence of PBND.
• Growing border crop of jowar (4 rows) with higher seed rate (@ 200 kg/ha) of groundnut treated with imidacloprid 600 FS @ 1 mL/kg of seed followed by foliar application with Acetamaprid 20 SP @ 0.2 g/L at 35-40 DAS reduces PBND incidence and thrips damage as well as increases pod and haulm yield.

Aflatoxin Contamination

• Blanching used in conjunction with manual and electronic sorting was very effective in eliminating aflatoxin-contaminated kernels. Roasting at 120 degree C for 12-15 min. or 140 degree C for 6-8 min. reduces the aflatoxin contamination.
• Groundnut in rotation with onion or garlic shown to reduce aflatoxin contamination in groundnut.
• Common salt or rock salt at the concentration of 20% or baking soda at 2% adversely affected the germination of flavus spores and also colony growth.
• Good Storage Practices for Groundnut Pods and Kernels: for protection from Stored Pests and Aflatoxin Contamination: Storage processing viz., sorting of pods, avoiding rewetting of pods before shelling, drying of kernel moisture content below 7%, storing of kernels in high density polybags having 160 micron thickness and roasting at 120^oC -140^oC cum blanching reduced the aflatoxin contamination in groundnut kernels
• Good Agricultural Practices for minimizing aflatoxin contamination in groundnut: Practices viz., rotation of groundnut with onion and garlic, summer ploughing, seed treatment with fungicide, application of gypsum, avoiding drought in pod development & maturity stage, inverted method of drying and drying of pods below 7% before packing reduces the aflatoxin contamination in groundnut.

ENTOMOLOGY Defoliators (Tobacco caterpillar, Gram pod borer, Hairy caterpillars and Leafminer)

• The sex pheromone @ 10:20:14 composition of (R)-(Z)-7, 9-Decadienyl acetate, E7-Decenyl acetate and Z7-Decenyl acetate with wota-T trap surface smeared with castor oil proved effective in trapping the male moths of leafminer (Aproaerema modicella).
• The modified trap was developed with reduced distance between the funnel and lid (from 4 to 2 cm) increased the efficiency in trapping the male moths of gram pod borer, Helicoverpa armigera.
• The per cent loss in pod yield due to the artificial defoliation by tobacco caterpillar, Spodoptera litura and gram pod borer, armigera varied from 21 to 25 during vegetative, 18 to 41 during pegging and 16 to 57 during maturity stage.
• Cyrtozema dispar (black weevil) was reported to be pest of groundnut.
• Management of defoliator pests like, Spodoptera litura and Helicoverpa armigera: A single spray of Rynaxypyr 20 SC @ 125 mL /ha on need basis.
• Management of Leaf miner (Aproarema modicella ): A single spray of Quinalphos @ 1000 mL/ha on need basis.

Sucking pests (Thrips, Leafhoppers and Aphids)

• Bajra/pearl millet (Pennisetum glaucum) as border crop (2 rows) along with 2% crude neem oil spray protects crop from thrips.
• The yellow sticky tray trap was found effective in trapping adult populations of both the leafhopper and thrips.
• Spraying spore suspension of Verticillium lecanii at 2.0 g/lt to manage the leafhopper and thrips populations, respectively.
• Bajra intercropped with groundnut (1:3) harboured lowest population of thrips, leafhoppers and aphids.
• Management of sucking pests: Seed treatment with imidacloprid 600 FS/thiamethoxam 30 FS @ 2 mL/kg of seed (1:3 ratio of chemical and water) reduces sucking pest incidence and protects the crop.

Storage pests (Bruchids, Flour Beetles and Rice Moths)

• Combination of 30±5ºC and >70% RH was found to be most congenial for bruchid, Caryedon serratus (Olivier) growth and multiplication.
• Tamarind (Tamarindus indica) was found most suitable for mass multiplication of bruchids in laboratory.
• On an average 1.9 adults only can emerge/kernel irrespective of the density of eggs.
• A positive relation was observed between the number of exit holes/kernel and the adult emergence.
• The castor oil, pongamia oil and eucalyptus oil @ 10% (v/w) and neem oil @ 5% (v/w) were found effective in reducing the bruchid oviposition and also the loss in pod weight.
• The super grain bags (78µm thickness) protected the stored groundnut up to 4 months period from the bruchids.
• Survey was conducted in Saurashtra region of Gujarat, samples were collected and sent for identification species were identified as Phyllognathus dionysius, Holotrichia serrate, and Holotrichia sp.
• Management of bruchid in stored groundnut: Disinfecting old jute bags with deltamethrin 2.5 SC @ 0.5 mL/L protect groundnut pods from bruchid infestation for six months of storage.

Integrated Pest Management

• State-wise IPM modules were developed comprising of basal application of castor cake @ 500 kg/ha (time of application as per the local practice) + seed treatment with Trichoderma sp. @ 4g/kg seed (locally available formulation) + intercropping (Andhra Pradesh: Groundnut + Redgram (7:1), Gujarat: Groundnut + Castor (3:1), Maharashtra: Groundnut + Soybean (4:1), Tamil Nadu: Groundnut + Castor (4:1) and Karnataka: Groundnut + Bajra (3:1)) + border crop of castor/bajra (collect egg mass and young larvae of Spodoptera litura) + need based application of crude neem oil (2%) + bird perches 50/ha + pheromone traps 10/ha + application of NPV @ 1.5 X 10¹³/ha when the larvae are 1^st to 3^rd instars + for leaf miner spray, NSKE @ 5% (if necessary one spray of recommended chemical when the pest is observed in mining stages) + for red hairy caterpillar (field drenching, trapping the larvae with calotropis branches and poison baiting (5 kg rice bran + 500 g jaggery + 500 ml quinalphos 25EC).

Nematology Plant-parasitic nematodes

• The infection of root-knot nematode, Meloidogyne arenaria and root-lesion nematode, Pratylenchus was detected in groundnut fields of Rajkot district (Gujarat) and West Midnapore region (West Bengal), respectively. The damage and reproductive potential of root-knot nematode, M. arenaria and M. incognita and their reactive oxygen species modulation in groundnut have been worked out.
• Soil drenching with fluorescent pseudomonads (Pf1 and Pf3 strains) was found effective in reducing the nematode egg hatching and juvenile mortality in Meloidogyne arenaria and incognita.

Entomo-pathogenic nematodes

• • • Two virulent entomopathogenic nematodes (EPNs), Heterorhabditis and Steinernema carpocapsae were found to be effective against larvae of S. litura.
    • The mermithid nematode parasitizing larva of Helicoverpa armigera (~40% parasitism) was recorded in groundnut fields of Junagadh district (Gujarat).

Crop Production Unit

Staff position in this unit

Water Management, Fertigation and Mulching

• • 1. Scheduling irrigation based on IW/CPE ratio of 0.8 is optimum.
    2. Crop residue mulch @ 5 t/ha reduces irrigation and increases yield.
    3. Pre-monsoon sowing with irrigation improves yield.
    4. IRWH system recorded highest yield followed by FBSS, BBF, and FB.
    5. Black polythene mulch increases yield by over 15%.
    6. Drip irrigation saves 33.2% water; fertigation saves 25% fertilizer.
    7. 75% NPK through drip improves yield over conventional methods.

Weed Management

• • 1. Alachlor or Pendimethalin with interculture operations is effective.
    2. Paired row planting reduces weed biomass.
    3. Ridge-furrow systems reduce weed population.
    4. Mulching reduces weed growth.
    5. Lasso and TOK E 25 combination is effective.

Nutrient Management

• • 1. Fertilizer is the most critical factor in kharif groundnut.
    2. Wheat straw mulch increases yield by 23%.
    3. Early planting with higher fertilizer increases yield by 34%.
    4. Water hyacinth can be used as organic manure.
    5. SSP is the best phosphorus source.
    6. Gypsum @ 750 kg/ha at flowering improves yield.

Cropping Systems

• • 1. Groundnut + sunflower intercropping increases yield.
    2. Paired row planting improves productivity and profit.
    3. Radish intercropping gives highest returns (B:C ratio 4.60).
    4. Groundnut-wheat-green gram system gives high sustainability (SYI = 0.92).

Other Practices

• • 1. Optimum sowing: second fortnight of January.
    2. Paired-row planting increases yield by 20–27%.
    3. Maintain soil moisture at -0.4 bar during harvest to reduce losses.
    4. Recommended practices increase yield by 32–46%.
    5. Dry seeding before monsoon gives maximum yield.
    6. Hydrogel improves yield under irrigated conditions.