Studies on Mango Leafhoppers Homoptera Cicadellidae With Special Reference to Seasonal Abundance Varietal Influence and Management in North Eastern Transition Zone of Karnataka

Abstract

newlineThe leafhoppers alone can cause 20-100 per cent inflorescence loss in mango during newlinevegetative and reproductive phases of the tree. They have different species composition newlineacross the mango growing area. The survey conducted across the different location of the newlinemango growing in Karnataka during 2016-17. The Shannon diversity index indicated that newlinediversity at surveyed places as Brahmavara (0.61), Bidar (0.60) and Shivamogga (0.56), in newlinecontrary least was observed within Gadag (0.35), Kolar (0.39) and Dharwad (0.41) district of newlinethe Karnataka. The dominance of the leafhoppers by Simpson index recorded that highest newlinewas in Brahamavara and Bidar i.e 0.32 each and lowest dominance was in Gadag (0.16), newlineKolar (0.19) and Dharwad (0.20). The richness by Margalef s index displayed highest was in newlineBelagavi (0.59) and Shivamogga districts (0.56), and least was observed in other districts newlineranged from 0.36 to 0.41. Based on the maximum availability, the ranking was made as newlinefollow; Idioscopus nitidulusgtAmritodus atkinsonigtIdioscopus nagpuriensisgtIdioscopus newlineclypealis. In the present experiment different leafhoppers populations were monitored on the newlinemango tree Kesar at College of horticulture, Bidar, during 2015-17 revealed that the I. newlinenitidulus was more (4.68 per sweep), followed by A. atkinsoni (3.65) and lastly I. newlinenagpurensis (3.23). During 2015-16, weather parameters such as maximum temperature and newlinerelative humidity (RH) showed significant positive correlation (r=0.59 to 0.74). Similarly, in newline2016-17, wind speed showed positive significant correlation (r=0.57 - 0.62) and no such newlinerelation were observed with other climatic factors. The varietal observations imply, the newlinevarieties like Raspuri, Langra and Kesar were infestated by moderate number of leafhoppers. newlineThe leafhoppers mean population were highest during the fruiting period in the varieties such newlineas Dasheri, Mulgoa, Neelum and Alphanso. The biochemical study shows that, the highest newlinequantity of phenol was observed in Mallika, Totapari, Mulgoa and the least was in Rasap