Correlation and regression studies on incidence of leaf roller, Diaphania pulverulentalis (Hampson). (Lepidoptera: Pyralidae) in mulberry

Abstract

The quality mulberry leaf and subsequent quality silk production is greatly hampered due to the incidence of defoliating insect pests. The maximum population buildup of the pest was recorded during September – October, 2017 with the incidence range of 35.67 to 40.12 per cent and July to September, 2018 (39.86 to 30.36 per cent). Further, the study revealed that, there was a linear relationship of the pest incidence with decreasing temperature and increasing relative humidity, under Chintamani conditions. Correlation analysis revealed that, there was a significant negative correlation between pest incidence with maximum temperature. All the other abiotic and biotic stress factors had a positive correlation with incidence of the leaf roller. However, multiple regression analysis revealed that none of these abiotic and biotic factors significantly influenced the population of leaf roller, D. pulverulentalis (Hampson) in mulberry.