INTEGRATED MANAGEMENT OF MELOIDOGYNE JAVANICA (TREUB) CHITWOOD INFECTING OKRA BY BACILLUS THURINGIENSIS BERLINER ISOLATES AND CHEMICAL FERTILIZERS
In the present studies three Bacillus thuringiensis isolates viz. BT-64, BT-16 and BT-14 alone and in combination with three different fertilizers namely urea, Di--ammonium phosphate (DAP) and potash were applied in soil @ 0.1% (w/w). Second stage juveniles (J2) of root-knot nematodes (Meloidogyne javanica (Treub) Chitwood) were released around roots of okra (Abelmoschus esculentus (L.) Moench. cv. Arka anamica) 15 days after seedling emergence. The effect of the treatments on the growth parameters and nematode population / g roots of okra plants were examined. All treatments significantly reduced the root galls, egg masses/root system and eggs/egg mass. Different developmental stages of M. javanica in okra roots were also recorded to assess the effect of combined treatments. Populations of J2, J3, J4 and female nematodes /g root declined with combined treatments of Bt isolates and chemical fertilizers.