The effects of phorate (Thimet) on the root knot nematode (<i>Meloidogyne incognita</i>) (Kofoid & White) chitwood infesting soyabean (<i>Glycine max</i> L. Merrill) and resultant effects on some biochemical components of seeds

Abstract

The effect of phorate (0,0-diethyl thiomethyl phosporo dithioate in controlling the root knot nematode Meloidogyne incognita (Kofoid & White) Chitwood infestation on Soyabean Glycine max (L.) Merrill and resultant effects on some biochemical components of the seeds were studied. Yield was tremendously improved by the phorate treatments in the 2 soyabean cultivars tested. Plants of cultivaz TGm 80 treated with phorate at the concentrations of 1000 and 1500 μg a.i./ml recorded more than double the seed weight recorded for the control plants. Significantly lower gall indices and nematode populations (P= 0.05) were recorded for treated plants when compared with the controls. Biochemical analysis of seeds from treated plants showed significantly (P = 0.05) higher crude fibre, fat/oil and phosphorus contents but lower protein and free fatty acids, contrasting with those of the controls. The values of free fatty acids, obtained for plants treated with 1500 and 1000 μg a.i./ml were less than half of those obtained for the controls in both soyabean cultivars TGM 80 and TGM 344.8

Keywords: Soyabeans, Meloidoqyne incognita, Phorate, Biochemical components of seeds.