The investigation was conducted on potato cv. Kufri Badshah durtng autumn season of 1994–95 and 95–96 at CCS HAU, Hisar. The treatments (6×3=18) consisted of combinations of six plant densities (47,619, 60,606 and 83,333 plants/ha adjusted in single row system and 95,238, 1,21,212 and 1,66,666 plants/ha adjusted in double row system) and three fertility levels of N:P:K i.e. recommended dose (100:60:80 kg/ha), 125 and 150 per cent of the recommended dose. The study reveal that plant height, stems/m2 and number of tubers/m2 increased with increase in plant density from 47,619 to 1,66,666 plants/ha. while leaf area index and dry weight of foliage increased with increasing plant density upto 1,21,212 plants/ha. The above parameters also increased with increase in fertility levels up to 150 per cent of the recommended dose. Yield of over size tubers decreased and that of under size increased with increase in plant density up to 1,66,666 plants/ha, whereas, fertility showed the reverse trend. The yield of seed size tubers as well as total tuber yield increased with increase in plant density up to 95.238 plants/ha and fertility levels up to 150 per cent of the recommended dose. The interaction between plant denSity and fertility level was significant and highest yield of total as well as seed size tubers was obtained with treatment combination of D4F3 (95.238 plants/ha adjusted in double row system with fertility level of 150 per cent of the recommended dose).
