Potential of natural enemy, Epiricania melanoleuca and Tetrastichus pyrillae against leaf hopper under sugarcane agro ecosystem in Bihar

Abstract

Potential of two natural enemies i.e. the nymph and adult parasitoid, Epiricania melanoleuca and the egg parasitoid, Tetrastichus pyrillae were studies during 2015-2016 against sugarcane leaf hopper, Pyrilla. Perpusill. Study revealed that the population of cocoons of Epiricania melanoleuca ranged from 0.10 to 3.7 per ten leaves and reached its peak (3.7 cocoon/ten leaves)) in the 2nd fortnight of August 2015.The minimum temperature with relative humidity (07 hrs and 14 hrs) and rainfall showed highly significant positive correlation with population of cocoons and the maximum parasitization of these natural enemy was recorded 61.4% on pyrilla during second fortnight of August, 2015. Thereafter, parasitization was observed in declined trend. Whereas weather factors i.e. minimum temperature, relative humidity and rainfall were showed highly positive significance relation with parasitization of Epiricania melanoleuca. In case of parasitization of pyrilla (eggs) by Tetrastichus pyrillae started parasitization from 1st week of June 8.56% and it was found increasing trend up to 100% in month of October and November. The weather parameters is concerned, the maximum temperature, relative humidity 07 hrs. Showed significant positive correlation with parasitization of (eggs) pyrilla.