Effect of date of sowing and weather factors on infestation of Atherigona soccata (Rondani) and yield parameters of forage sorghum

Abstract

Ecofriendly strategies for the management of sorghum shoot fly, helps in addressing the Atherigona soccataissues related to insecticides load on forage crop. The present study was carried out to know the suitable date of sowing on damage indices of sorghum shoot fly and green fodder yield in sorghum. The staggered sowing technique at a different time intervals was used, starting from 2 fortnight of March (12 SMW) to 1 fortnight of ndthstJuly (27 SMW). Oviposition in terms of eggs per 10 plants and dead heart percentage was recorded to be low thin 18 SMW (1 fortnight of May) sown crop (eggs: 6.66 and dead heart: 25.46%), but it was found to be highest thstin 1 fortnight of July (27 SMW) sown crop (eggs: 21.95 and dead heart: 65.45%). The correlation of shoot fly stthinfestation in relation to weather parameters revealed that egg load and dead hearts were negatively correlated with maximum temperature and positively correlated with minimum temperature, relative humidity and rain fall. Green fodder yield was recorded to be highest and lowest for the crop sown on 18 SMW (409 q/ha) and 27 ththSMW (302 q/ha), respectively. The study indicated that 1 fortnight of May was the best time to escape from the stsorghum shoot fly attack.