Effect of Pest Exclusion Net (PEN) on the Sustainable Production of Late Season Broad Leaf Mustard (BLM) in Chitwan, Nepal

Abstract

Broad leaf mustard (BLM) (Brassica juncea L. var. rugosa, Brassicaceae) is one of the most widely consumed vegetable crops in Nepal. The production of crop in open field is constrained by major pests like mustard aphid and flea beetle. This study was aimed to determine the effects of pest exclusion net (PEN) on pest-infestation and yield of BLM cultivar "Khumal Broad Leaf". The experiment was carried out in randomized complete block design (RCBD) with five treatments and four replications. The treatments included control (no mulch + no net + no pesticide spray), black plastic mulch only, reflective plastic mulch only, black plastic mulch + no net + pesticide spray, and PEN + black plastic mulch + no pesticide spray. Data were analyzed with RSTAT software package and means were separated by Duncan's multiple range test (DMRT) at 5% level of significance. The result revealed that crop under PEN had highest plant height (38.99 cm), lowest number of aphid (0-0.86 per plant), flea beetle (0-1.07 per plant) and highest total marketable yield (77.50 ton/ha) while control had lowest plant height (20.06 cm), highest number of aphid (maximum 2.49 per plant), flea beetle (maximum 2.00 per plant) and lowest total marketable yield (13.75 ton/ha). Economic analysis revealed highest benefit-cost ratio in PEN (9.90). This study indicates that the use of PEN protect BLM against aphid and flea beetle, increases yield and can be considered as a viable technology for BLM production by smallholder growers of Nepal.

Effects of different mulches and net house on crucifer aphid (Brevicoryne brassicae L.) population, growth and yield of broadleaf mustard (Brassica juncea)

“…This vegetative parameter was superior in reflective mulch compared to black plastic mulch as reflective mulch has repellent characteristics against aphid and other small insects. Neupane et al (2018) also reported the highest yield attributing characteristics in broadleaf mustard inside net house + black plastic mulch followed by black plastic mulch + imidacloprid spray, reflective mulch and black plastic mulch.…”

“…The problem associated with pesticide use can be overcome by growing crops in a protected environment such as net house and use of mulching materials. Growing crops inside the net house (Neupane et al, 2018;Bhusal et al, 2019) and use of mulching (Orozco-Santos et al, 1995) lower insect pest population and increase yield. Therefore, this study was carried out to evaluate the efficacy of different mulching materials and net house against crucifer aphid of broadleaf mustard during the winter season in Chitwan, Nepal.…”