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20222
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Subject: Entomology × End date: 2022 × Start date: 2022 × Thesis Type: Ph.D ×
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    ThesisItemOpen Access
    Studies on insect pest complex in pulses, biology and management of spotted pod borer, Maruca vitrata (Fabricius) in green gram, Vigna radiata (L. Wilczek)
    (CCSHAU Hisar, 2022-07) Sonu Kumari; Balbir Singh
    The current studies entitled “Studies on insect pest complex in pulses, biology and management of spotted pod borer, Maruca vitrata(Fabricius) in green gram, Vigna radiata (L. Wilczek)” was carried out at CCSHAU Regional Research Station, Bawal and oilseed section, Deparment of Genetics and Plant Breeding during Kharif 2020 and 2021. Survey revealed that the population of leafhopper (6.96 leafhopper/plant), hairy caterpillar (0.85 larvae/plant), aphid (12.04 aphid/plant), whitefly (7.71 whitefly/plant), spotted pod borer (2.75 larvae/plant), blister beetle (13.24 adults/plant) and tur pod bug (6.63 bugs/plant) was more abundant in Gurugram district as compared to Mahendragarh and Rewari. The seasonal incidence revealed that the larval population of spotted pod borer increased significantly with maximum temperature (r=0.956 and 0.761) and showed significant negative correlation with rainfall (r=-0.823 and -0.911) during Kharif 2020 and 2021, respectively. The biology of spotted pod borer, M. vitrata showed that total developmental period (egg to adult) was 34.35±1.62 days. The fecundity of female moth was on an average 47±5.48 eggs/female. The treatment azadirachtin (0.03%) was found most effective protectants resulted in reduction larval population (4.32 larvae /m2), per cent pod damage (12.94%) and highest grain yield (13.01 q/ha) as well as per cent increase yield over control (35.69%) followed by neem oil (20 ml/l) and neem seed kernel extract 5 per cent (50 ml/l). The trichome density on leaves and pods and pod breadth was responsible for the resistance to spotted pod borer. Whereas, pod size, number of grains per pod and pod wall thickness were associated with the susceptibility to M. vitrata. Expression of resistance to spotted pod borer infestation was associated with higher amount of phenol content, low amount of soluble sugar and crude protein in pods as well as grains of pulses crop.
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    ThesisItemOpen Access
    Population dynamics and eco-friendly management of major insect-pests on tomato under open field and polyhouse conditions
    (Chaudhary Charan Singh Haryana Agricultural University, 2022-04) Dharmendar Singh; Rajesh Kumar
    The present studies entitled “Population dynamics and eco-friendly management of major insect-pests on tomato under open field and polyhouse conditions” were carried during the years 2019 and 2020 at farm area of CCSHAU Krishi Vigyan Kendra, Jhajjar and at farmers’ field, Village Surajgarh, Block Matanhail, Distt. Jhajjar (Haryana). The population dynamics was studied on seven varieties of tomato viz., Hisar Arun, Hisar Lalit, Pusa Ruby, Pusa Rohini, Red Cherry, Sona Cherry and Kesar Cherry under open field conditions. The population of whitefly (Bemisia tabaci) was recorded from 9th SMW with its peak during 12th SMW on varieties Hisar Lalit, Pusa Ruby and Pusa Rohini. The whitefly remained present on most of the varieties up to 15th SMW. Leaf hopper (Amrasca devastans Ishida) remained present on tomato from 7th SMW till 18th SMW with its peak during 13th and 14th SMW. The fruit borer (Helicoverpa armigera Hubner) population appeared in 10th SMW on Hisar Lalit, Pusa Ruby and Hisar Arun varieties of tomato with its peak in 16th and 17th SMW being highest on Punjab Sona Cherry (5.53 larvae/plant). The whitefly population showed non-significant positive correlation with the maximum temperature, minimum temperature, wind speed and rainfall whereas non-significant negative correlation with the relative humidity. However, pest population of leafhopper and fruit borer exhibited significant positive correlation with maximum and minimum temperature whereas significant negative correlation with the relative humidity. Number of branches/plant, pericarp thickness, average fruit weight and number of fruits per plant exhibit significant negative correlation with the whitefly population. Leafhopper population exhibited significant positive correlation with pericarp thickness. The correlation coefficient revealed negative significant correlation between number of branches/plant and fruit borer population. Under polyhouse conditions, the maximum temperature and minimum temperature of 33.5oC and 18.7oC, respectively and relative humidity 70 per cent favoured peak population build-up of whitefly under polyhouse conditions whereas the maximum temperature, minimum temperature and relative humidity of 33.5oC, 18.7oC and 70 per cent, respectively were congenial for peak population build-up of leaf miner. Seven eco-friendly insecticides were evaluated against Helicoverpa armigera on tomato under open field conditions. The highest larval reduction over untreated control was recorded in Spinosad 45% SC (85.80%) whereas it was lowest in Dashparniark (54.71%). All the insecticidal treatments proved statistically better than untreated control in lowering the fruit damage (weight basis) due to fruit borer on tomato. No significant adverse effect was observed due to different insecticidal sprays on the population of natural enemies Coccinella spp., Chrysoperia carnea and Menochilus spp. Under polyhouse conditions, out of 6 eco-friendly insecticides, Spinosad 45% SC @ 188 ml/ha proved to be most effective treatment in keeping the population of whitefly and leaf miner at significantly lowest level. Neem oil @ 0.3% was found to be the next most effective treatment Beauveria bassiana (1% wp 1x108 cfu/g) against whitefly and leaf miner, respectively. The cow urine based formulations viz. Brahmastra, Neemastra and Dashparniark were found least effective among all the treatments but significantly better than untreated control.