A study on Maruca vitrata infestation of Yard-long beans (Vigna unguiculata subspecies sesquipedalis)

Abstract

Globally, Maruca vitrata (Geyer) is a serious yield constraint on food legumes including Yard-long bean (Vigna unguiculata subspecies sesquipedalis). However, there is a dearth of information on its damage potential, distribution and population dynamics in Yard-long beans. In the present study, the level of M. vitrata larval infestation on flowers and pods of Yard-long beans in Sri Lanka was determined with respect to three consecutive cropping seasons, Yala, Off and Maha. Results indicated that larval infestation and abundance varied with developmental stage of flowers and pods, cropping season and their combined interactive effects. Flowers of Yard-long beans were more prone to M. vitrata larval attack compared to pods. Abundance and level of infestation of M. vitrata varied with plant parts, having a ranking of flower buds (highest) > open flowers > mature pods > immature pods (lowest). Peak infestation was observed six and eight weeks after planting on flowers and pods, respectively. Among the three cropping seasons, M. vitrata infestation was found to be higher during Maha and Off seasons compared to Yala. The findings of this study contribute to the identified knowledge gap regarding the field biology of an acknowledged important pest, M. vitrata, in a previously understudied crop in Sri Lanka.

Constraints and solutions of country bean (Lablab purpureus L.) Production: A review

“…Shoot borer (Acrobasis caryae) and field cricket (Brachytrypes portentosus) were also found in winter and summer season, respectively in Sylhet. In Bangladesh ( Table 2) [24,25] . Das et al (2014) [26] noted frequency of five key insects and mite infested of bean field in Bangladesh.…”

“…Among them country bean is a very important crop in Bangladesh as cultivated in whole year. From the [14,23,25,26,32,40,41,42,43] . [23,25,32,44,45] .…”

“…From the [14,23,25,26,32,40,41,42,43] . [23,25,32,44,45] . Leaf beetle Karim 1995; Jayasinghe et al2015 [24,25] .…”

“…[23,25,32,44,45] . Leaf beetle Karim 1995; Jayasinghe et al2015 [24,25] . Epilakhna beetle Khan et al2018;Karim 1995; Jayasinghe et al2015 [23,24,25] .…”

Volatiles from Maruca vitrata (Lepidoptera, Crambidae) host plants influence olfactory responses of the parasitoid Therophilus javanus (Hymenoptera, Braconidae, Agathidinae)

“…Maruca vitrata caterpillars predominantly feeds inside plant organs. Feeding starts from the green, unopened flowers, with growing caterpillars moving to older flowers and ultimately pods where it completes its development ( Bailey, 2007 , Jayasinghe et al, 2015 ). Feeding inside growing cowpea pods might incur less mortality risks (e.g.…”