Evaluation of systemic chemicals for the control of rotylenchulus reniformis on papaya

The reniform nematode Rotylenchulus reniformis was found highly pathogenic to papaya in India and Hawaii and responsible for papaya decline }n Hawaii. There is meagre information on the control of this nematode in papaya with systemic nematicides. Investigations were carried out to evaluate the systemic chemicals for the control of this nematode and it was found that carbofuran at the rate of 2 Kg a.i./ha significantly increased the yield by 38.4% over the control, closely followed by aldicarb sulfone and aldicarb. It was also observed that there was significant reduction in soil nematode population six months after the treatment compared to pre-treatment population in field condition. Pot culture studies also revealed that there was significant reduction in soil population by aldicarb and disulfotan treatments. In the nursery application of phorate and fensulfothion at the rate of 0.4 g a.i./m2 increased shoot height and vigour of the seedlings.