Comparative efficiency of root and foliar application of macro and micronutrients to correct mineral deficiencies in the rice plant grown in nutrient solution

Abstract

Rice plants cultivars IAC 47 (upland) an IAC 435 (lowland) were grown in nutrient solution either under low levels of N, P, K or S, or in the absence of B, Cu or Zn. At the tillering stage the deficient element was supplied via nutrient solution or through leaf feeding. Yield data and leaf analyses allowed for the following general conclusions to be drawn: (1) the deficiency of a given element affected differently grain production in the two varieties; (2) for a given nutrient the same nutritional status, i.e., "normal" or "deficient" could be defined by different leaf levels; (3) additional yield (due to corrective measures) divided by quantity of element applied was higher in the case of foliar feeding of macronutrients; the opposite took place in the case of micronutrients.