RESPONSE OF KUFRI-MEGHA POTATO (SOLANUM-TUBEROSUM) TO NITROGEN, PHOSPHORUS AND THEIR INTERACTION IN ACIDIC SOILS OF MEGHALAYA

A field experiment was conducted during the summer seasons of 1990 and 1991 to study the response of 'Kufri Megha' potato (Solanum tuberosum L) to N and P in acidic soils. The variety under north-eastern hill c onditions was tested at different combinations of 4 levels of N (0, 50 . 100 and 150 kg/ha) and 4 levels of P (0, 35, 70 and 105 kg/ha). Bein g a long-duration variety, its response to P was higher compared with the other varieties ('Kufri Jyoti'). The highest tuber yield (20.1 ton nes/ha) was obtained with the application of 100 kg N + 70 kg P/ha. Th e optimum doses of N and P were 129 and 90 kg/ha respectively. The int eraction between the 2 nutrients was significant. The uptake of N incr eased significantly up to 1 00 kg N/ha with 70 kg P/ha. However, signi ficant uptake of P was observed up to 105 kg P/ha with 100 kg N/ha. Tu bers accounted for 83% of the N and P uptake; the haulms accounting fo r the rest. The mean recovery of applied N and P was 38.3 and 7.1% res pectively.