Phosphine fumigation for control of bamboo borer, Dinoderus minutus Fab. infesting bamboo culms and products

Abstract

Wood of bamboo is gaining more popularity in India for various applications replacing the usage of conventional timber of high priced tree species. Currently, many species are available in market for different purposes such as handicrafts, furniture, structural material and bamboo composites etc. Freshly felled bamboos are prone to attack by ghoon borers, mainly Dinoderus minutus Fab. (Coleoptera: Bostrychidae). The attack leads to powdering and loss of strength of bamboo culms. Chemical treatments by various methods like spraying or surface application may not yield desirable results as the larvae dwell inside the culms with least exposure to outside. In this context, fumigants like phosphine can be useful to effectively penetrate the culms and kill the existing infestations. Hence, in the present investigation, phosphine gas at different dosages (0.5, 1.0, and 1.5 mg/L) was tested against adult borers and their immature stages by in vitro testing. Mixed-age culture of D. minutus (cultured in cut bamboo and tapioca chips) containing young and old adults and different stages of larvae were used for the study. Phosphine fumigation was carried out in 2.85 L desiccators for an exposure period of 96 h. Subsequently, post-fumigation studies indicated that all the three dosages of phosphine caused 100 % kill of all life stages of D. minutus. The results reveal that the use of phosphine fumigation for controlling wood borers in bamboo handicrafts and other artifacts can be further exploited.