EFFECTS OF FENAMIPHOS AND BIOCONTROL AGENTS ON COTTON GROWING IN NEMATODE-INFESTED SOIL

Efficacy of a chemical nematicide, fenamiphos and three microorganisms in controlling Rotylenchulus reniformis and Tylenchorhynchus latus on cotton planted in field plots was investigated. Monthly records of th e nematode population levels showed that fenamiphos had the highest (p less than or equal to 0.05) levels of their control which resulted in the top cotton yield. Plots receiving the bacterium Bacillus sp. had various degrees of nematode control though their cotton yield was comp arable (P less than or equal to 0.05) to the fenamiphos-treated plots. Plots inoculated with a fungus Chaetomium spirale recorded the least effect for controlling the two nematode species and their cotton yield was not significantly different from the untreated plots. Plots treat ed with an actinomycete, Streptomyces sp., had an intermediate effect on both nematode population densities and cotton yield. At harvest, T. latus population densities were equally suppressed (P less than or eq ual to 0.05) in all treatments which should be reflected on the subseq uent crop.