Effect of intra row spacing, dates of haulm cutting and fertilizer dose on disease free quality seed tuber production of potato (Solanum tuberosum L.) under new Alluvial Zone of West Bengal

Abstract

Potato (Solanum tuberosum L.) is the most popular tuber crop in West Bengal, India. Seed tuber is the single most important factor in potato cultivation and if the seed is not of good quality, then optimum production could not be achieved. Unavailability of good quality seed, high price and untimely supply of seed at the village level are the main limiting factors in potato production. Field experiments were conducted during rabi season of 2017-18 and 2018-19 at Bidhan Chandra Krishi Viswavidyalaya, Kalyani, West Bengal to determine the effects of intra row spacing, dates of haulm cutting and fertilizer dose on disease free quality seed grade tuber production of potato. The experiment was laid out in a split split plot design with three replications having twelve treatment combinations. The results revealed that with the decrease in intra row spacing from 20cm to 15cm seed grade size (< 75g) tuber yield and numbers and total tuber numbers were significantly increased but marketable grade (> 75 g) tuber yield and numbers were significantly reduced. Haulm cutting at 65 DAP increased the seed grade size tuber yield and numbers over 75 DAP. With the decrease in fertility levels from 100% RDF of NPK to 50% RDF of NPK the seed grade tuber production and number were significantly increased at 5% level of significance. Disease incidence and intensity of Phoma leaf spot decreased and early blight increased with decreasing doses of fertilizers. No viral disease was observed. Dehaulming at 65 DAP was found safer so far as infestation and chances of viral disease transmission by the sucking pests were concerned. From the present study it may be concluded that, for quality seed tuber production of potato and to get highest net return under New Alluvial Zone of West Bengal, use of 50cm X 15cm spacing along with haulm cutting at 65 DAP, when planting is done on first week of November and grown with 50% RDF of NPK was found best.