Studies on the seasonal incidence of stem borer Chilo partellus Swinhoe and sorghum shoot fly Atherigona soccata Rondani on maize and their management

Abstract

The present investigation entitled Studies on the seasonal incidence of stem borer, Chilo partellus Swinhoe, and sorghum shoot fly, Atherigona soccata Rondani, on maize and their management was carried out during , 2016-2017 at Students Instructional Farm (SIF) of Chandra Shekhar Azad University of Agriculture and Technology, Kanpur (UP). The initial occurrence of C. partellus during Kharif - 2016 and 2017 caused 4.20 and 2.80 per cent mean number of dead hearts, respectively, during the 30th SMW i.e. at 33 DAS (Days after sowing), during both the years. The pest population increased gradually and reached its peack on 33rd SMW (Standard Meteorological Week) i.e. 53 DAS with a formation of mean number of dead hearts i.e. 28.10 and 27.80 per cent, respectively. The correlation matrix for both the years indicated a non significant negative correlation with maximum temperature (r = - 0.188 and r = - 0.056, respectively) with maize stem borer infestation. However, non significant positive correlation; except positive significant correlation with minimum temperature in 2017 was observed with other meteorological parameters viz. minimum temperature (r = 0.161 and r = 0.472*, respectively), total rainfall (r = 0.280 and r = 0.277, respectively) and average relative humidity (r = 0.137 and r = 0.250, respectively). The initial infestation of A. soccata during Kharif - 2016 and 2017 was noticed by causing 4.80 and 5.60 per cent mean number of dead hearts, respectively, during the 27th SMW i.e. at 13 DAS, during both the years. The pest population increased gradually and reached its peack on 30th SMW i.e. 34 DAS with a formation of mean number of dead hearts i.e. 21.60 and 20.80 per cent, respectively, The correlation matrix indicated a non significant negative correlation with maximum temperature r = - 0.348 in the years 2016 and significant negative correlation in 2017 i.e. r = -0.512* with sorghum shoot fly infestation was observed. However, non significant positive correlation was observed with minimum temperatures