Effect of different proportion of organic and inorganic nutrients on productivity and profitability of potato (Solanum tuberosum) varieties in Meghalaya hills

A field experiment was conducted during summer seasons of 2005 and 2006 at Shillong in split plot design having three potato varieties in the main plots and six organic-inorganic nutrient combinations in the sub-plots with four replications. Among the varieties, Kufr i Megha recorded significantly higher tuber yield when compared with Kufri Giriraj and Kufri Jyoti. Number of tubers/plant, mean tuber weight, marketable and total tuber yield of potato increased significantly due to the use of recommended dose of fertilizers (RDF) i.e. 120-52.4-50 kg N-P-K/ha or 75% RDF + 25% recommended dose of N (RDN) through FYM. The yield components and tuber yield decreased gradually as the crop received higher proportion of plant nutrients through FYM. Accordingly, substitution of RDN by FYM resulted in lower tuber productivity which was significantly lower than those of other organic-inorganic combinations except control. Kufri Megha receiving RDF or 75% RDF + 25% RDN through FYM produced the highest tuber yield (27.11/26.98 t/ha) among all treatment combinations. High net return was obtained from the crop receiving 100% RDF or 25% RDN through FYM + 75% RDF. Kufr i Megha at RDF or 75% RDF + 25% RDN through FYM may be recommended for better growth, higher tuber yield and greater net return from potato cultiva- tion in the North Eastern Hill Region of Meghalaya.