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Subject: Entomology × Author: Dharmendar Singh × Start date: 2010 × Type: Thesis ×
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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.