Effect of seed treatment chemicals and pruning on seed-potato (Solanum tuberosum) production of 'Kufri Bahar' under Allahabad condition

The effects of seed treatment chemicals [no seed treatment (control set)], Gibberellic acid, Benzyl adenine and urea and pruning: no tipping (control set), tipping, tipping + Maleic hydrazide, tipping + Triodo benzoic acid were assessed in 'Kufri Bahar', a semi-vigorous, input-responsive mid-season potato variety at Allahabad during 2007-08. Tipping was found to have significant effect over non-tipping treatment. Plant height was increased significantly (62.83 cm) by the seed treatment chemicals. Gibberellic acid treatment showed maximum plant height, followed by urea (nitrogen) and Benzyl adenine, respectively. Tipping reduced plant height but insignificantly. Pruning chemicals (Maleic hydrazide and Triodobenzoic acid) were found to reduce plant height significantly when applied after tipping. Those inhibitors were also found to suppress the effect of seed treatment chemicals (Gibberellic acid, Benzyl adenine and urea). Plant height was recorded in the range of 62.83 cm in T-4 to 34.80 cm in T-2. Number of shoots/plant, top fresh weight, underground fresh weight, top dry weight and underground dry weight were significantly affected by seed treatment chemicals and pruning and the range was 12.25-3.45, 290.88-176.76 g, 54.26-28.68 g, 159.44-96.44 g and 30.78-14.98 g, respectively. Number of tubers/plant were also influenced by the treatments. Gibberellic acid yielded more number of tubers followed by urea, Benzyl adenine and minimum in the control set. Maleic hydrazide and Triodobenzoic acid were found to reduce number of tubers/plant. Tipping with chemical seed treatment increased number of tubers/plant significantly. Contrary to this, number of economic tubers/plant were recorded more when seed-treated plants were tipped, followed by Maleic hydrazide and or Triodobenzoic acid spray. Number of seed tubers/plant was adversely affected by tipping. Seed treatment chemicals yielded higher number of seed tubers/plant. Tipping followed by Maleic hydrazide and or Triodobenzoic acid spray displayed significantly better results and highest number of seed tubers/plant (10.73) were observed in T-7, while lowest (5.57) was observed in T-2. Similarly, yield of seed-tubers/ha was highest (35.66 tonnes/ha) in T-7 and lowest (13.06 tonnes/ha) in T-2. Seed treatment chemicals and tipping were found to enhance the vigour and productivity of potato plant. Seed treatment with GA(3) @ 50 mg/litre, water and tipping at 25 days after seed sowing, followed by spraying with Triodobenzoic acid @ 15 mg/litre at day 3 of tipping may be recommended to the farmers to get higher yield of seed-potato in cv. 'Kufri Bahar' under Allahabad condition.