Present study was carried out at R.A.K. collage of agriculture, Sehore (M.P.) during experimental year Kharif 2016
, four varieties of soybean JS-335, JS-9305, JS-9560 and RVS-2001-04 were studied upon the impact of climatic factors on the incidence of soybean’s Grey semi-looper (Gesonia gemma
) and Green semi-looper (Chrysodeixis acuta
). Weather data of maximum, minimum temperature, rainfall, relative humidity of Kharif
-2016 was collected (June standard weather week 26 to October Standard weather week 42) from the national observatory. Monsoon arrival and date of sowing and difference in number of days between these two parameters was also taken into consideration for correlation with the incidence of Gesonia gemma
and Chrysodeixis acuta
. Activity of the Gesonia gemma
on different varieties of soybean was observed at low level. The season mean of pest population per 2 meter row length was 0.83 in JS–335, 0.69 in JS-95-60, 0.71 in JS-9305, and 1.12 in RVS-2001-04 varieties. Larval population of Chrysodeixis actua
was also remained at very low level in all the four varieties of soybean. The correlation study revealed that the population of Chrysodeixis acuta
was not correlated with date of sowing after monsoon. The maximum temperature in 2016 was negative but significantly correlated with the season mean larval population of both insects while larval population of only Gesonia gemma
was negatively and significantly correlated with minimum temperature in 2016. Data of first appearance of pest in day after germination was correlated with the seasons mean larval population the correlation was negative and significant in case of Gesonia gemma
while in Chrysodeixis acuta
it was positively significant.
Hemant Kumar Verma, Dr. Rajesh Verma, Anand Rao Azad and Rajesh Aggarwal. Impact of climatic factors on the incidence of soybean leaf feeders. J Pharmacogn Phytochem 2020;9(3):577-580.