Fertilizer recommendations based on targeted yield concept involving integrated nutrient management for potato (Solanum tuberosum) in tarai belt of Uttarakhand

Abstract

Soil-test crop response of potato (Solanum tuberosum L.) was studied in Mollisol during winter (rabi) season, 2006– 07. Four levels of fertilizer N, P, K and 3 levels of farmyard manure were randomly distributed in 24 plots and 3 fertility strips with a total of 72 plots. Soil and plant analysis data were exploited to formulate fertilizer adjustment equations for each strip with and without farmyard manure at varying yield targets at different fertility levels. Co-efficient of determination (R2) was found significant (0.614**) between yield and soil test values. Based on the experiment, the nutrient requirement for producing 100 kg of potato tuber was 0.33 kg of N, 0.05 kg of P and 0.40 kg of K. The per cent contribution from soil was 20.01, 8.02 and 19.84; from applied farmyard manure 12.82, 1.32 and 14.49 and from fertilizer 15.41, 5.43 and 26.21 for N, P and K, respectively. Verification trial of this experiment was done in the next season, ie during winter (rabi), 2007–08. The variation in yield obtained from the targeted yield ranged from +9.77 to –9.76%. The farmers’ practice of fertilizer application and control were least efficient in producing tuber yield of potato. Both the highest cost : benefit and response ratio was found with farmyard manure 10 tonnes/ha + yield target 2000 kg/ha.