Evaluation of trellis system for pest management in bitter gourd

To investigate the response of different trailing systems against insect pests of bitter gourd, a trial was conducted under field conditions for two consecutive years (2012–13 & 2013–14) in rabi season along with simultaneous assessment of their response on natural enemies. The findings clearly indicated that the fruit borer infested fruits was minimum in trellis system (12.19 and 13.57%) followed by non-trellis system (22.58 and 24.14%) followed by bower system (32.14 and 30.86%). Similar trend was also observed for fruit borer and fruit fly population during the same period. The maximum yield and highest cost:benefit ratio (138.07 q/ha and 1:7.25) was observed in trellis system. Regarding natural enemies, different trellis system showed positive response against coccinellids, spiders and grubs of chrysoprela. Fertilizer application, manual weeding, pesticide spraying insect pest monitoring and manual irrigation was found easier in trellis system. Highest cost:benefit ratio and least pesticide hazard due to drift was also found in trellis system.