Effect of Plant Phenology on Infestation by Legume Pod Borer <i>Maruca vitrata</i>on Dolichos Bean

Abstract

The legume pod borer Maruca vitrata (F.) (Crambidae: Lepidoptera) causes considerable yield loss in major edible legumes including dolichos bean Lablab purpureus var. typicus. This study analyses the M. vitrata incidence and abundance in relation to the four plant parts during two consecutive cropping seasons of 2019. The results revealed that peak incidence of 80.00 ± 2.83% was in the 11th week after planting during rabi, 2019, and it was more in unopened flower buds (64.00 ± 8.76%) and mature pods (13.00 ± 0.80%). There existed significant differences between the four growth stages of the crop in the order- flower buds (maximum) ˃ mature pods ˃ immature pods ˃ open flowers (least) during summer 2019. The occurrence of single and multiple larvae was more in the unopened flower buds (78.00 ± 3.35%) and mature pods (52.00 ± 3.35%).