Abstract

The sorghum earhead bug Calocoris angustatus Lethierry population at pre-flowering. milky, dough stage and maturity stage of earhead was influenced by three weeks average weather parameters. Morning and evening relative humidity were positively correlated with the population while maximum and minimum temperature and wind velocity were negatively correlated in all the stages of the earhead. The regression equation of three weeks mean was found to have maximum regression co-efficient representing most appropriate equation in all the stages of the earhead. Evening relative humidity showed positive influence while rainfall had negative effect during pre-flowering stage. At milky stage, moming relative humidity and minimum temperature exhibited positive effect while maximum temperature, evening relative humidity, wind velocity and rainfall effected negatively. The positive effect was noticed with maximum temperature, evening relative humidity and rainfall while the negative effect was observed with minimum temperature and moming relative humidity in dough stage. In maturity stage the population was negatively influenced by maximum temperature, wind velocity and rainfall.

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