Comparative Studies on the Performances of Some Plant Cakes and Synthetic Chemicals Against Nematodes in Tea in Bangladesh

Abstract

A comparative study was undertaken to evaluate the performances of plant cakes and synthetic chemicals against nematodes infesting tea at Bangladesh Tea Research Institute (BTRI) during March 2012 to June 2012. The indigenous plants i.e. Bishkatali (Polygonum hydropiper), Mahogani (Swietenia mahagoni) and Neem (Azadirachta indica) and synthetic chemicals i.e. Carbofuran (Furadan 5G), Fipronil (Goolee 3GR) and Rynaxypyr (Ferterra 0.4G) were considered as treatments. The dose of tested plant cakes @ 50g/pot and synthetic chemicals i.e. Furadan 5G @ 35g/pot, Fipronil 3GR @ 35g/pot and Rynaxapyr 0.4G 15g/pot were used in this experiment. Soil samples are regularly collected at weekly interval and samples were analyzed for nematode count at Entomology Laboratory through Baermann funnel method. Result revealed that all the treatments had showed the toxic effect on nematodes and significantly reduced nematode population from the soil. The nematode population in the soil treated with Rynaxypyr 0.4G was the lowest due to the highest mortality of nematodes (85.80%) followed by Fipronil 3G (82.00%), and Carbofuran 5G (81.71%) which was satisfactory. Among the plant cakes, Mahogani cake showed the highest (79.89%) mortality of nematodes in the treated soil. The cakes of Bishkatali (74.82%) and Neem (71.57%) also reduced the nematode population significantly. Rynaxapyr and Mahagani Cake can be used as soil treatments for the management of nematodes to get nematode free soil or safe soil with less nematode for establishing tea nursery. Crude plant cakes of P. hydropeper, S. mahagoni and A. indica can effectively be utilized beside the use of chemical nematicides as safer nematicidal products in integrated pest management of nematodes in tea in Bangladesh.