Kuldeep Srivastava

Seasonal dynamics and management of whitefly ( Bemesia tabaci Genn.) in tomato ( Solanum esculentum Mill.)

ABSTRACT Studies on seasonal dynamics of white fly (Bemesia tabaci) on tomato (Solanum esculentum var. Pusa Ruby) revealed that it appeared first during the 13 th and reached maximum during 21 st standard meteorological week. A positive correlation between adult population and abiotic factors viz. temperature (maximum and minimum) and sunshine hours was observed, whereas humidity (maximum and minimum) and rainfall showed a negative correlation with it. Taken together, the key weather parameters studied, caused 89.00 per cent variation in whitefly population (R 2 value). Combination of carbofuran (soil application) + imidacloprid (seed treatment ) + imidacloprid (foliar application) proved significantly superior and caused maximum reduction in whitefly population followed by imidacloprid (seed treatment) + thiomethoxam (spray), imidacloprid (seed treatment) + imidacloprid (spray), imidacloprid (seed treatment) + dimetheoate (spray), carbofuran (soil application) + malathion (spray), and imidacloprid (seed treatment) + yellow sticky traps. The highest cost benefit ratio of 1:25.04 was recorded in case of carbofuran (soil application) + imidacloprid (seed treatment ) + imidacloprid (foliar application) followed by 1:22.38 for imidacloprid (seed treatment) + thiomethoxam (spray) ; 1:21.81 for imidacloprid (seed treatment) + imidacloprid (spray); 1:19.27 imidacloprid (seed treatment) + dimetheoate (spray); 1:19.48 carbofuran (soil application) + malathion (spray), and 1:8.33 for imidacloprid (seed treatment) + yellow sticky traps. The soil application of carbofuran + seed treatment with imidacloprid and three foliar sprays of imidacloprid at fortnight interval starting 40 days after transplanting is found effective and is advised for whitefly management in susceptible tomato cultivars.

Seasonal incidence and management of wheat aphid, Sitobion avenae (F.)

Experiments conducted on the seasonal incidence of Sitobion avenae F. during 2010–2011 and 2011–2012 at the University Farm of Sher-e-Kashmir University of Agricultural Sciences and Technology-Jammu revealed that it was @ 2.16 aphids/shoot in the 5th standard week and reached maximum (10.04 aphids/shoot) in the 11th standard week. The maximum and minimum temperatures had positive and significant effect (r = 0.719* and r = 0.565*), while relative humidity and rainfall had negative and significant correlation (r = - 0.425* and r = - 0.462*). Imidacloprid 200SL (0.008%) was the most effective in reducing population followed by thiamethoxam 25WG (0.0125%), dimethoate 30EC (0.03%), oxy-demeton methyl 125EC (0.03%), quinalphos 25EC (0.05%), clothianidin 50WDG (0.025%), acetamiprid 20SP (0.06%), flubendiamide 480SC (0.003%) and neem seed kernel extract (NSK) (5%). The maximum yield was recorded with imidacloprid (32.65 q ha−1) followed by thiamethoxam (31.72q ha−1) and dimethoate (30.59 q ha−1). The highest cost:benefit ratio (1:24.78) was obtained with dimethoate and the lowest in flubendiamide.

Plants For Bees: Brankad: Adhatoda vasica Nees

Value to Bees The plant is entomophilous, honeybees being the dominant pollinators. Successful pollination of Moringa flowers requires large number of insects’ visitations. The flowers are visited by Hymenoptera (Apis dorsata, A. mellifera, A. cerana, Xylocopa latipes, X. pubescens, Megachile sp. and Halictus sp.), Lepidoptera (Lycaenidae, Danaidae, Papilionidae and Pieridae), Coleoptera (Coccinella spp.), and Diptera (Syrphids, House flies, etc.) (Table 1). The A. dorsata and A. mellifera forage heavily on the plant for pollen and nectar. Besides these, humming birds (Mellisuga sp.) have also been observed to be active on Moringa flowers. The Jammu and Kashmir, a major ecological unit with rich diversity is having an abundant scope for natural/organic products. The conservation and propagation of M. oleifera flora will help to develop the beekeeping activities and in turn enable beekeepers can collect surplus honey during the blooming period.