Dhirendra Singh

Resistance to yellow vein mosaic virus in okra: a review

Okra (Abelmoschus esculentus L. Moench) is an important vegetable grown throughout the world mainly for its immature fruits. Yellow vein mosaic virus (YVMV) transmitted by white fly (Bemisia tabaci Gen.) is the most serious disease of okra affecting both yield and fruit quality. Since the disease cannot be controlled properly by chemical means, the only practical solution of this problem is to develop tolerant/resistant varieties. Much work has been done to determine the inheritance of resistance to YVMV in okra and to identify different sources of resistance. In this review efforts have been made to elucidate the genetics of resistance to YVMV in okra and also to provide complete information regarding sources of resistance.

Impact of biodynamic preparations and panchgavya in organically managed cropping systems comprising legumes on soil biological health

Biological health of soil was assessed to understand the effect of varingly managed organic cropping systems under field conditions. Twelve treatment combinations comprised two cropping systems (CS1-Basmati rice-Chickpea-Sesbania green manure ;CS2-Basmati rice-Vegetable pea-Maize (green cob & Fodder) + Green gram (residues incorporation) and six organic nutrient manangement practices- T1: Farmyard manure + Vermicompost + Enriched Compost + Neem Cake, T2: Biodynamic Preparations, T3: Farmyard manure + Vermicompost + Enriched Compost + Neem Cake + Panchgavya, T4: Farmyard manure + Vermicompost + Enriched Compost + Neem Cake + Biodynamic Preparations, T5: Farmyard manure + Vermicompost + Enriched Compost + Neem Cake + Biodynamic Preparations + Panchgavya, T6: Control. The highest activity of different soil enzymes viz., dehydrogenase, acid, alkaline and total phosphatase; and aryl sulfatase was assessed to the tune of 1311.02 µg Tri Phenyl Formazan 24h-1g-1 soil at flowering in ‘spring’, 26.99 µg p-nitrophenol h-1g-1 soil, 35.19 µg p-nitrophenol h-1g-1 soil, 62.18 µg p-nitrophenol h-1g-1 soil and 77.75 µg p-nitrophenol h-1 g-1 soil at harvest of ‘rabi’ crop, respectively receiving the organic nutrient package through T5. Significantly enhanced microbial population and their biomass facilitating the enhanced mineralization of nitrogen to the tune of 150.10 µg NH4+-N g-1 soil with nutrient management practices employed through T5 was observed.