The authors studied the effect of new types of slow-release micronutrient fertilizers on crop production in the Himalaya. These were biorelease fertilizers of zinc, iron, manganese, copper, boron, and molybdenum synthesized in a laboratory. Trials were conducted at Pithoragarh (1240 m), Kumaon Himalaya, with radish (Raphanus sativus) followed by amaranthus (residual effect; Amaranthus blitum), and at Auli (2900 m), Garhwal Himalaya, with cabbage (Brassica oleracea L. var. capitata) and thereafter lahi (residual effect; Brassica rugosa). Increases in yields of radish of 61% and increases in its vitamin C content by 105% were observed with low dosages of micronutrients. The yield of cabbage also increased by 98%, and its vitamin C content increased by 46%. In the residual effect trial, lahi (a leafy vegetable) produced a remarkable 164% increase in yield that was statistically significant at a 1% level. Overall, the data suggest that biorelease fertilizers are very effective at low dosages. They would be particularly suitable for crop production in mountainous regions.
