Screening of Soybean Germplasm against Spodoptera litura (Fab.) for the Expression of Antixenosis Resistance Through Seasonal Incidence and Dual-feeding Assay

Soybean, [Glycine max (L.) Merr.] is an important kharif growing crop and affected by a number of insect pests which are directly or indirectly decrease the yield. To increase the yield, the infestation by insect pest should be managed. Spodoptera litura is considered as the major pest of soybean crop and damages soybean to a very extent. Cultivation of insect resistant soybean can be the best technique for pest management program. Insect resistance is usually conferred by antixenosis i.e. the set of plant characteristics and insect responses that lead to undesirability of host. Thus, to find out the antixenosis resistance among 16 germplasm this study was performed.

Seasonal incidence of S. litura was recorded with the abiotic parameter. Antixenosis resistance was determined through non-choice and free-choice feeding assay likewise MLAC (cm²) and C-value were calculated to find out the preference or non-preference of soybean germplasm. Trichome density and length were also examined which aids in the resistance mechanism.

Incidence of pest show positive correlation with temperature and morning humidity. The data on area consumption and C-value of soybean signified the resistant germplasm (BAUS 102, DSB34, MACS 1493 and RSC 11-03) and highly susceptible germplasm (NRC 131 and RSC 11-07) against S. litura which also conferred indirect relationship with trichome density and length.