Relative abundance of major insect pests and natural enemies in high yielding rice varieties of Assam (original) (raw)
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Journal of entomology and zoology studies, 2017
Fixed plot survey carried out during Kharif season (August to December) 2013 for insect pests and natural enemies complex of paddy ecosystem in different location of Cauvery command areas of Mandya district (nearby Vishveshvaraiah canal farm, Mandya). Among the pests, yellow stem borer, plant hoppers, gall midge and leaf folder were very severe and in case of predators, mirids and spiders were most important natural enemies. The average yield loss in rice has been estimated 21-51 %. The population of yellow stem borer was significantly positively correlated to Hymenopterans, Odonata and Staphylinids, whereas BPH is positively correlated with mirids (r=+0.770**), spider spider (r=+440*), odonatan (r=+0.700**), coccinellids (r=+0.476*), carabids (r=+0.779**) and cicindelids (r=+0.417*). In the same way white backed plant hopper, skipper, caseworm, hispa, blue beetle & grass hopper recorded positive significant and positive non-significant with the predators and parasitoids.
Seasonal incidence of insect pests of rice at Pajancoa and RI, Karaikal, U.T. of Puducherry
The Seasonal incidence of insect pests of rice were studied with a light trap during Kharif 2019 and Rabi 2019-2020. The results exhibited that yellow stem borer, Scirpophaga incertulas was first observed during 28 th meteorological standard week (0.14) and its activity gained momentum from August to November (Kharif 2019) and January to February (Rabi 2019-2020) and reached its highest peak during 43 rd MSW (2.86) and green leafhopper, Nephotettix virescens commenced during 47 th MSW (1.43) and populations reached its highest level during 1 st MSW (4.86) and 4 th MSW (5.29). Brown planthopper, Nilaparvata lugens occurred first during 50 th MSW (0.29) and its major activity was observed during 1 st MSW (2.29) and 3 rd MSW (1.86). White leafhopper, Cofana spectra arrived first during 48 th MSW (0.29) with highest peak of population during 3 rd MSW (1.71) during Rabi 2019-2020.
2017
The yellow stem borer (YSB) (walker) is one of the most serious insect pests infesting field rice crop. The relative abundance of different natural enemies in relation to the interaction with the environmental factors and also in relation to the incidence of YSB was studied in view of the three growth stages of kharif rice at Murshidabad, West Bengal, India, during 2016. The incidence of natural enemies was found to vary in relation to the YSB incidence. Collectively, 262.75 lady bird beetles (LBB) ware counted. Numerically Long jawed spider ranked second with 97.30 individuals. This was followed by wolf spider (32.53), lynx spider: LS (19.87), carabid beetle (38.44), damsel fly (33.67), dragon fly (15.28) in descending order. Least was noted for wasp (14.70) population. All of the insect natural enemies had very steady correlation with YSB population. Rank order of relative abundance of natural enemies in kharif rice field. Lady bird beetles (51.06%)> Long jawed spider (18.91%) ...
Journal of Applied and Natural Science
Rice is the cereal grain that feeds half the planet. Rice fields are economically important as well as ecologically valuable. Rice fields are one of the biggest ecosystems that can be found in the tropics, including diverse insect pests and their natural enemies. In this view, rice varieties were sown in experimental plots of Faculty of Agriculture, Annamalai University, Chidambaram. The values are found significant at 5% level. To monitor the pest and natural enemies by using net sweeping and yellow pan trap method was used. The results showed that the maximum number of yellow stem borer was observed in the direct-seeded rice variety of CR Dhan 209 (7.33) and the leaf folder population was maximum in the direct-seeded rice variety of CR Dhan 204 (7.33). The peak population of grasshopper and green leafhopper was recorded in the transplanted rice variety of CR Dhan200 (11.33), CR Dhan 209 (8.00). The values were found significant at 5% level. The maximum number of Braconidae was obs...
2017
An experiment was carried out under field conditions at the Agricultural Research farm of Institute of Agricultural Sciences, Banaras Hindu University, Varanasi to study the seasonal abundance of major insect pests of rice, during kharif, 2014-15. Incidence of yellow stem borer was started from last of July with its peak during second week of October and showed a positive significant correlation with evening and average humidity and a positive non-significant correlation with morning humidity and rainfall. BPH appeared in rice crop during first week of August and reached at highest level during 2nd week of October. Later on the population decreased as the crop reached the harvesting stage. The correlation analysis of Brown plant hopper revealed a positive non-significant correlation with rainfall, temperature and relative humidity. The incidence of leaf folder infestation was commenced during first fort night of August and the larval population increased gradually till 38th week wit...
2017
An experiment was carried out under field conditions at the Zonal Agricultural Research Station (ZARS), Vishveshvaraiah Canal(V. C) Farm, Mandya district of Karnatakato study the population status of major sucking insect pests of rice in different methods of planting. Incidence of BPH was started from last of July and its mean population was observed in mechanical transplanted rice of 4.40 followed by manual (3.87) drill sown (2.16) and aerobic method (1.06) nymphs and adults per hill respectively. Whereas WBPH was recorded at 30 DAT and incidence remained up to the 90 DAT and Ear head bug incidence started with panicle initiation stage and continued till dough stage of the crop, and its mean population was non-significant differences among the different methods of planting. KeywordsEar head bug, BPH, WBPH, Rice ecosystem Introduction Rice (Oryza sativa L.), is the important cereal food of world and India. In India rice is grown over an area of 42.86 M. ha. with a production 104.3 M...
Insect-pests complex associated with basmati rice in Western Uttar Pradesh
The Pharma Innovation Journal, 2021
Present investigation was carried out at Crop Research Centre (CRC) of Sardar Vallabhbhai Patel University of Agriculture & Technology, Meerut during Kharif season, 2019 and 2020 to assess the insect-pests complex associated with basmati rice in Western Uttar Pradesh. Results revealed that in total eleven different insect species were found infesting the basmati cultivar PB-1509. Insect-pests includes borers viz. yellow stem borer (Scirpophaga incertulas Walker), sucking pests viz. brown plant hopper (Nilaparvata lugens Stal.), green leaf hopper (Nephotettix virescens Distant), white backed plant hopper (Sogatella furcifera Horvath) and earhead bug (Leptocorisa acuta Thunberg), defoliators viz. leaf folder (Cnaphalocrocis medinalis Guenee), rice Hispa (Dicladispa armigera Olivier), kharif grasshopper (Hieroglyphus banian Fabricius), army worm (Mythimna separata Walker) and caseworm (Nymphula depunctalis Walker) and root feeders viz. termites (Odontotermes obesus Rambur) were found damaging the crop during both the seasons. Severity of pests varies due to the environmental and other factors.