Comparative performance and economic efficiency of different pesticides against okra jassids (Amrasca biguttula biguttula): Their impact on okra yield and growth attributes

Abstract

Okra is a vegetable of high economic importance. Among many pests attacking it, jassids are considered to be the major one. Considering the impacts of jassids on yield reduction of okra, health hazards due to chemical pesticides and the high cost of chemical pesticides, a field experiment was conducted in olericulture farm of Agriculture and Forestry University in April, 2019 to assess the comparative performance and economic efficiency of different pesticides against okra jassids; their impact on yield and growth attributes. The pesticides Mugwort green leaves @200g/L, Justicia green leaves @200g/L, Neemix @2ml/L, Nitenpyram @2ml/L and an untreated plot i.e. control was chosen as treatments. Nitenpyram was found to be significantly (P<0.05) superior to Neemix, Justicia, Mugwort and control for percent reduction in okra jassids (84-93%) after 48 hours of spray. Both Nitenpyram and Neemix treated plot were statistically (p<0.05) similar for yields (26 mT/ha and 22.4 mt/ha respectively). Nitenpyram was superiorly significant (p<0.05) for okra plant height, biomass and fruit length from rest of the treatments. The correlation between the percent reduction of pests and yield of okra was found to be 0.733, 0.789, 0.859 and 0.74 (all at p<0.01) for the 4 sprays. The benefit cost ratio was highest for plot treated with Justicia (1.78) followed by Neemix, Nitenpyram, mugwort and control. Thus, it would be better to suggest the okra growing farmers of Chitwan to use Nitenpyram for maximum reduction of jassids but for yield purpose Neemix can be suggested for a better yield without using chemical pesticide. Justicia and Neemix both would prove to be economically efficient owing to their high BC ratio (1.78 and 1.65).