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Field efficacy of different bio-inputs and insecticides against melon fruit fly, Zeugodacus cucurbitae (Coquillett) in bitter gourd was carried out in farmer’s field. The effect of different bioinputs (ITK concoction) and insecticides were superior over control in reducing the fruit fly damage and increasing yield. The application of spinosad 45 SC and chlorantraniliprole 18.5 SC gave maximum fruit yield (12,200 and 14,540 kg/ha) and (11,780 and 13,950 kg/ha) followed by agniastram (10,950 and 13,600 kg/ha), karpurakaraisal (10,570 and 13,095 kg/ha) in Kharif and Rabi, respectively. The minimum fruit yield was recorded in ten leaf extract (9560 and 11,110 kg/ha) during Kharif and Rabi. The benefit cost ratio was maximum in spinosad 45 SC (1:2.33 and 1:2.81) and chlorantraniliprole 18.5 SC (1:2.18 and 1:2.61) followed by agniastram (1:2.14 and 1:2.56), karpurakaraisal (1:2.20 and 1: 2.40) in Kharif and Rabi.

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Aim: To evaluate the effect of abiotic factors such as temperature, relative humidity, wind velocity, sunshine hours and rainfall on the distribution and relative abundance of stem borer species in rice ecosystem. Methodology: Seasonal incidence of stem borer species was monitored using light trap catches and were correlated with the weather parameters. The relative abundance of stem borer species during Kharif and Rabi was estimated based on light trap catches and larval incidence. Results: Seasonal incidence revealed the occurrence of three stem borer species (yellow stem borer, pink stem borer and dark headed borer) populations in rice ecosystem. Yellow stem borer was found to dominate in rice ecosystem during Kharif, (80.61%) whereas during Rabi, pinkstem borer was found to be dominant (72.60%) than yellow stem borer (21.92%) and dark headed borer (5.48%). Weather parameters such as temperature, rainfall and wind velocity negatively influenced the occurrence of stem borer species in rice, whereas relative humidity and sunshine hours had positive effect. Regression analysis revealed the increased effect of abiotic factors such as temperature, relative humidity and wind velocityon the population of pink stem borer against yellow stem borer and dark headed borer. Interpretation: The present study reveals that, the change in weather parameter during seasons, such as temperature (25 - 27°C), relative humidity (69 - 80 %) and wind velocity (3 - 4 km hr-1) increased the fitness of pink stem borer species population than yellow stem borer and dark headed borer species in rice ecosystem, which was evidenced by the occurrence and relative abundance of pink stem borer population during Kharif 2018 and Rabi 2019 respectively.

Background: Bitter gourd, an important tropical and sub-tropical vegetable which occupies a predominant position in Indian vegetables. The aphids and leafhoppers are more serious agricultural insect pests and aphids indirectly transmit plant virus diseases like, Cucumber Mosaic Virus (CMV) in cucurbit crops. Our study aimed to noticed seasonal fluctuations and bio-inputs using management of sucking pests in bitter gourd.Methods: Field experiments were conducted during 2017-19 in a farmer’s field at Ellamanam village, Tiruchirappalli district, Tamil Nadu in insect pest population was monitored at weekly intervals from ten randomly selected plants in three plots. In field efficacy studies conducted Randomised Block Design with eight treatments and three replications. Result: Our results showed in the maximum aphid and leafhopper populations were recorded in September 2018 during 39th SMW (Standard Meteorological Week). In Rabi, the aphids and leaf hopper population were maximum in 9th and 10th SMW in February and March. The population of aphids and leafhopper were positively correlated with maximum temperature, minimum temperature, wind speed and wind direction. Rainfall and relative humidity were negatively associated to aphids and leafhopper infestation. In Kharif and Rabi, high reduction of aphid and leafhopper pest population were noticed in chlorantraniliprole 18.5 SC and spinosad 45 SC compared to control. Among the bio-inputs agniastram recorded higher reduction of pest population followed by karpurakaraisal, NSKE, fish acid and ten leaf extract.

Oviposition preference of Spodoptera frugiperda was studied on both monocot (rice, maize, sorghum, cumbu, cumbu napier, ragi and sugarcane) and dicot plants (cotton, castor, groundnut, sunflower, red gram, black gram and cowpea) under the laboratory condition. S. frugiperda moths highly preferred bottom and middle canopy of maize and cumbu napier for oviposition than other plants in both the free choice and no choice tests. In no choice test, S. frugiperda laid eggs on all the monocot and dicot plants except black gram, red gram and cowpea, in free choice test it completely prefered monocot plants. In monocots, pre oviposition period was shortest on cumbu napier (2.52 ± 0.22) and longest on ragi (3.79 ± 0.21), oviposition period was shortest on ragi (5.20 ± 0.19) and longest on maize (6.20 ± 0.36), egg mass per plant was maximum on maize (5.2 ± 0.57) and eggs per egg mass were maximum on sorghum (105 ± 19.89), egg mass per plant and eggs per egg mass were minimum on ragi (2.6 ± 0.54 and 45.8 ± 8.25). In dicots, pre oviposition period was shortest on cotton (4.20 ± 0.20) and longest on groundnut (5.62 ± 0.23), oviposition period was shortest on groundnut (3.33 ± 0.28) and longest on castor (5.04 ± 0.16), minimum egg mass per plant and eggs per egg mass were recorded on groundnut (2.9 ± 0.54 and 4.2 ± 3.56) and egg mass per plant was maximum on cotton (4 ± 0.79), eggs per egg mass were maximum on castor (47.8 ± 3.34).

Background: In India, out of the total loss incurred by different insect pests of paddy, 25 to 30 per cent damage is done by stem borer alone. Many conventional insecticides though have been evaluated against stem borers, yet, most of the chemicals have failed to provide adequate control. Hence, the present study aimed to evaluate the efficacy of some newer molecules of insecticides and bio-control agents.Methods: Field trials were conducted to record the seasonal incidence and to evaluate the efficacy of insecticides and bio-control agents against the stem borer species in rice during Kharif and Rabi. Result: Field experiments revealed that during Kharif 2018, chlorantraniliprole 18.5 SC was highly effective with 92.98 and 91.24 per cent reduction of stem borer infestation over control at vegetative and reproductive stages, respectively and recorded a high yield of 5720 kg/ha followed by spinetoram 11.7 SC with 83.16 and 80.82 per cent reduction of stem borer over control at vegetative and reproductive stages, respectively. During Rabi 2019, spinetoram 11.7 SC was highly effective with 92.36 and 93.73 per cent reduction of stem borer infestation over control at vegetative and reproductive stages respectively and recorded a high yield of 4570 kg/ ha, followed by chlorantraniliprole 18.5 SC with 84.60 and 91.48 per cent reduction of stem borer at vegetative and reproductive stages, respectively. The difference in the efficacy of insecticides during Khaif, 2018 and Rabi, 2019, might be due to shift in the species occurrence of stem borer, with a dominant occurrence of yellow stem borer (80.61%) in Kharif 2018 and pink stem borer (70.00%) in Rabi, 2019. The bio-control agent Trichogramma japonicum exerted minimum reduction of stem borer with a low grain yield of 3946.6 kg/ha.