Influence of Climatic Changes on the Abundance of Major Insect Pests of Sugarcane

Abstract

The abundance of major sugarcane insect pests like top shoot borer, stem borer and rootstock borer were investigated for the last 28 years from 1980 to 2007 at Ishurdi, Pabna. The incidence of these major insect pests occurs in the months of March to October. The abundance of top shoot borer, Scirpophaga excerptalis Walker, was positively correlated with rainfall (r = 0.448*) in the month of June, where temperature and humidity did not affect significantly on their incidence. Stem borer, Chilo tumidicostalis Hampson, was found positively correlated with average maximum temperature in July (r = 0.399*), and negatively correlated with average minimum temperature in October (r = −0.379*) where humidity and rainfall did not affect significantly on their incidence. The abundance of rootstock borer, Emmalocera depressella Swinhoe, was positively correlated with average maximum temperature (r = 0.525**), and negatively correlated with rainfall in the month of May (r = −0.563**) and September (r = −0.380*). Top shoot borer and rootstock borer infestation were increased by 2.09 and 1.43%, respectively, during the last 28 years. Maximum and minimum temperature was increased by 0.18% and 0.22%, respectively, in the month of May during the last 28 years.