Unit

The Crop Protection Unit comprised of nine scientists (one Principal Scientist, three Senior Scientists and four Scientists) and required Technical Officers.

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).

1. Water Management, fertigation and mulching
   1. Scheduling of irrigation can be done better on the basis of depletion of available soil moisture or on the ratio of irrigation water and cumulative pan evaporation (IW/CPE). The ratio of (IW/CPE) of 0.8 wasfound optimum for scheduling irrigation in groundnut.
   2. Use of crop residue mulch @5 t/ha helped to reduce irrigation requirement and increased pod yield of summer groundnut.
   3. Pre-monsoon sowing with one or two irrigations before the onset of monsoon was found to increase pod yield substantially.
   4. The significantly higher pod yield was recorded in IRWH over flat bed. However, the order of pod yield was IRWH (1797 kg/ha) > FBSS (1785 kg/ha) > BBF > FB.
   5. Black polythene mulch was found to enhance seed germination, nodulation, nitrogen fixation, biomass production and pod yield (over 15%) significantly in rabi-summer season. Retention of the wheat straw mulch in combination with black polythene up to pod development stage further increased the pod yield in summer groundnut.
   6. Irrigation water can be applied at 6-day intervals through drip or 15-day intervals through check basin method without significant reduction in yield and economic returns over 4-day intervals through drip or 10-day intervals through check basin method during summer groundnut. Further, fertigation with 75% NPK resulted in saving of 25% fertilizers besides improving the productivity and economic returns. Drip irrigation also saved 33.2% irrigation water over conventional method.
   7. Use of polythene mulch significantly improved pod and haulm yields of kharifgroundnut by 5 and 20.7% over no mulch, respectively. Application of 75% NPK through drip significantly improved pod and haulm yields by 12.0 and 18.9% over 50% NPK. Thus, effecting saving of 25% NPK with drip irrigation over RDF with check basin method of irrigation.

   
   Weed Management

   1. Pre-sowing soil incorporation of alachlor @1.5 kg ai/ha, or pre-emergence application of pendimethalin @1.0 kg ai/ha along with 2 intercultural opertions at 30 and 45 days after sowing have been recommended for effective and economical control of weeds in groundnut.
   2. The weed population decreased with narrowing row spacing and pairing of rows (30-60-30 cm) could decrease dry matter of weed by 26.7% compared to single row planting.
   3. Altering land configuration like ridge and furrow, and broad bed and furrow decreased weed population and increased groundnut.
   4. Application of surface mulches like organic residues or polythene mulch also helped in reducing weed population in groundnut.
   5. Combination of weedicides Lasso and TOK E 25 @1.5 kg a.i./ha with suitable agronomic practices could control weeds effectively and gave higher monetary returns.
   6. Based on results of two years’ experimentation (kharif1988-89) on planting pattern and weed control, it was concluded that both the factors significantly effected pod yield and weed dry matter; moreover treatments of paired row planting and weed free condition were found as most effective.

   
   Nutrient Management

   1. Fertilizer was found to be the most critical production factor limiting groundnut production during kharif. The other important critical factors were: improved variety, plant density, and plant protection.
   2. Wheat straw mulch @ 5 t/ha was found to increase pod yield by 23% over the control in rabi-summer season by making available optimal quantities of nutrients and retaining sufficient soil moisture. It also maintained higher organic carbon content in soil than unmulched crop.
   3. Early planting with an increased dose of fertilizer and a plant density of 4.4 lakh/ha was found to increase pod yield by 34% as compared to conventional practice.
   4. It was observed that water hyacinth (Eichorniacrassipes) a common aquatic weed, could be successfully used as a source of organic manure in groundnut production.
   5. Single super phosphate (SSP) was found to be the most suitable form of phosphorus for increasing production.
   6. A number of varieties were evaluated for fertilizer responsiveness during summer and kharif1982-1984. Among the many varieties tested, GAUG-1, TG-17, TMV-12, M-13, S-206, TG-1, Kisan, Gangapuri and C-501, DH 3-30, SB-XI, TMV-12 and MH 1 were more responsive to higher fertility levels.
   7. Based on the continuous field trials (1989-90) studying the effect of gypsum application on groundnut yield showed that the application of gypsum @ 750 kg/ha at peak flowering stage of crop as top dressing was most effective to increase yield and yield attributes. Though the residual effect of gypsum on pod yield was not evident but a significant cumulative effect of gypsum of previous two years was observed while repeated the similar experiment in the next year (1991).
   8. Based on the field trials (Rabi-summer, 1993-95) to study the effect of mulching with N treatment on soil nutrient availability revealed that soil N was higher in wheat straw mulch over black polythene mulch at both 30 and 60 DAS with basal application, while no significant changes in soil P and K content was observed.
   9. Application of 37.5 kg N, 30.8 kg Pand 24.9 kg K/ha improved summer groundnut yield over RDF (25:22:0 kg NPK/ha) besides improving soil fertility.
   10. Maximum pod yield of summergroundnut was obtained with the application of 40-60-60 kg NPK (AS-SSP-MOP)+10:2:1 kg Fe Zn B/ha over the other combinations of treatments.
   11. Application of 20-40-30 kg NPK (urea-DAP-MOP)+250 kg gypsum+10:2:1 kg Fe Zn B/ha produced maximum pod yield while haulm yield was maximum in treatment 12.5:25:0 kg recommended NPK + 5 t +500 kg gypsum/haduring kharif
   12. Application of 25 kg N, 26.4 kg Pand 24.9 kg K/ha significantly improved the productivity of kharifgroundnut over RDF (12.5 kg N and 17.6 kg P_/ha).

    
   Cropping systems

   1. Intercropping groundnut with sunflower resulted in a further increase in pod yield by 18%. Criss-cross planting of groundnut was found to result in 14% increase in yield over the normal planting.
   2. By intercropping sunflower (one row) with paired row planting of groundnut, total oil production per unit area and time could be increased by 42% and 20% over sole crop of groundnut planted with normal and paired-row systems of planting, respectively. The optimum time for planting sunflower as an intercrop with groundnut was found to be 30 days after the sowing of groundnut.
   3. Over three years’ experimentation (1988-90) on plating pattern (normal and paired row) and intercropping (with Sesamum, sunflower and castor) with groundnut revealed that sunflower was found to be most suitable intercrop. Paired row planting was most effective in terms of pod yield and economics. Inclusion of intercrop with groundnut enhanced total oilseed output, oil yield and profit.
   4. Pod yield of groundnut was the highest (2820 kg/ha) when fenugreek was intercropped and lowest with spinach. Fresh vegetable yield was the highest in radish followed by spinach. Highest net returns and B:C ratio (4.60) were recorded in intercropping with radish
   5. Sole groundnut yielded 39.9% less under triphosphate than monophosphate. Pigeon pea yielded significantly higher in triphosphate than monophosphate. Groundnut yielded under intercrop did not vary significantly among the three sources of phosphorus.
   6. The highest total system productivity in terms of groundnut pod equivalent yield (2451 kg/ha) and net returns (` 33541/ha) were obtained with groundnut with FYM (5 t/ha)+50% RDF, wheat with FYM (5 t/ha)+50% RDF and green manuring with green gram in the groundnut-wheat-green gram cropping system The sustainable yield index was highest (SYI=0.92) in groundnut (FYM+50% RDF)-wheat (100% RDF).

    
   Other practices

   1. For summer groundnut, sowing time, planting density and balanced fertilizer were found as critical production factors. Second fortnight of January was found to be the optimum.
   2. Paired-row planting (with a gap of 22.5 cm between two rows of a pair and 45 cm between pairs) was found to be more efficient in accumulating dry matter and biomass production than the traditional systems and also supported lesser weed population. It increased pod yield by 20-27% over the wide row system (90 cm between rows) practiced in the Saurashtra region of Gujarat state. The method is being adopted in several areas of the Saurashtra.
   3. Among the varieties, Kadiri 3 showed its superiority over other varieties in paired row planting.
   4. By changing the planting pattern from set-row with 90 cm between rows, as practiced in Saurashtra, to a paired-row with constant seed rate, the yield could be increased substantially. Results of demonstrations conducted at farmers’ fields in Junagadh and Amreli districts of Gujarat revealed an increase in yield by 20-27% due to paired-row system over farmer’s practice.
   5. Pod losses during harvest, is a serious problem, especially in case of spreading varieties. The losses were recorded in the range of 15-26% in the farmers’ fields of Saurashtra region of Gujarat. Pod losses could be minimized by maintaining a soil moisture potential of -0.4 bar during harvesting period.
   6. From the two years field trial based on the economic seeding (summer 1983-1984) to study the effect of cut seed (half the portion removed) on germination and yield of groundnut, it was observed that pod yield was not affected in GAUG 1, JL-24, Kisan, MH 1, and RG 15 as compared to other varieties tested.
   7. During kharif1985 and 1986, maximization trialswere conducted to compare the superiority of proven technology (recommended practice) with the farmers’ practice in groundnut cultivation. It was revealed that recommended package of practices showed higher pod yield ranging 32-46% over the farmers’ practice. Total return was also higher when proven technology was adopted.
   8. The interactions between fertilizer × time of sowing and fertilizers × time of sowing × population density were found to have significant effect on pod yield and economic returns over the kharif
   9. To identify the most critical production factors contributing high yield in kharifgroundnut, field trials have been conducted over continuous three years (1989-91). Results indicated that pre-monsoon sowing was the most critical factor towards more yield and net return in the kharif sown crops.
   10. To study the yield variation through plant population in groundnut a field experiment was conducted over three years (1992-94) by taking seeds of different maturity (immature seeds to over-mature seeds) groups of spreading cultivar M 13 and bunch cultivar GG 2. It was concluded that the highest pod yield, number of pods/plant, pod weight/plant and shelling percentage was achieved in the mature seeds invariably over the years.
   11. Napropamide in controlling weeds (Monocots/Dicots) was similar to Pendimethalin. However, there was considerable residual effect on succeeding wheat germination but not in gram and no significant reduction in dry matter of green gram and pearl millet was observed.
   12. The pod yield was maximum when dry seeding was done 5 days before onset of monsoon. Seed coating with CaSO₄, Rock phosphate and cow dung showed some potential.
   13. Pod and haulm yields of kharifgroundnut were significantly higher under irrigated condition over rainfed condition. Furthermore, application of hydrogel @ 1.5 kg ha^-1 significantly improved pod and haulm yields over control and was at par with succeeding levels.
   14. Application of 2 t FYM+2 kg citric acid/ha improved both pod and haulm yields of summer groundnut and also fetched higher economic returns.
   15. Application of hydrogel @ 2.5 kg/ha along with integrated nutrient management and polythene mulch were found significantly better for obtaining higher productivity and economic returns from summer groundnut under drip irrigation.