Department of Plant Sciences

Need based nutrition by soil or leaf analysis is the most scientific way of nutrient management in horticultural crops, but this approach is not possible in the limited resource situation in India. India’s 6.3 million hectares under horticultural crops are managed in about 2.2 million farm holdings, since the average land holding is low at 2 ha. Analyzing soil / leaf samples from all 2.2 million farm holdings once or twice every year and giving fertilizer recommendation is practically impossible, since the infrastructure and skilled manpower needed for soil and leaf analysis and for interpretation is enormous. But due to the liberalized international economy and free trade in horticultural commodities, Indian farmers need to be competitive in terms of yields, quality, sustainability in supply and profitability in terms of better input use efficiency in fertilizer and also for avoiding environmental pollution. Hence instead of establishing nutrient needs for a micro farm situation, a macro level monitoring was done for crops (mango, banana, orange) for micronutrient disorders within an agro-ecological zone. Based on the results of this survey, foliar formulations of micronutrients were prepared for each crop and used to correct visible and sub clinical deficiencies. This technique has been used in India already for correcting iodine deficiency in humans with iodised common salt (NaCl) and is successful in correcting sub clinical disorders.