10.Effects of different insecticides on cowpea aphid (Aphis craccivora Koch)
Roshan Dhakal, Reeta Ghimire, Madan Sapkota, Samita Thapa, Atal Kumar Bhatta and Jiban Shrestha
Abstract: Aphid (Aphis craccivora Koch) is one of the serious pests of cowpea. Bio efficacy of four insecticides with different concentrations namely Jholmol (125 ml/L), Neemix (2 ml/L), Cannabis extract (100 g/L), Chloropyrifos 50% EC and Cypermethrin 5% EC (2 ml/L) along with control were evaluated against aphid at Research Station of Agriculture and Forestry University, Rampur, Chitwan, Nepal in 2018. Five treatments; four different insecticides and control were laid out in randomized complete block design with four replications. The results indicated that all the insecticides were significant for aphid reduction. The effects were higher in Neemix followed by Jholmol and cannabis extract. Yield of cowpea was significantly highest (11.10 t/ha) with Neemix application, while lowest in control (7.58 t/ha). The highest net profit (NRs.61670) was obtained in Neemix followed by treatments of Jholmol (NRs.46175) and Cannabis extract (NRs.35815). The lowest incremental Cost/Benefit ratio or ICBR was obtained in Neemix (1.341) and followed by treatments of, jholmol (1/1.12) and Cannabis extract (1/0.85), respectively. Thus, application of Neemix @ 2 ml/L could be used in cowpea to control aphid with high yield. Keywords: Aphid (Aphis craccivora Koch), insecticides, bio efficacy, cowpea.