Enhanced yield and nutritional enrichment of seeds of Pisum sativum L. through foliar application of zinc

Zinc deficiency has been identified as a major nutritional constraint for optimum crop yield. The study was conducted to determine the period of growth and optimum concentration for foliar application of Zn to improve yield and nutritive quality of seeds of pea (Pisum sativum L. var. IPFD-99-13), an important edible legume. Foliar application of Zn (0.01, 0.1 or 0.5% ZnSO4) to plants supplied low Zn (0.1 μM Zn as ZnSO4) produced significant increase in yield parameters viz. number of flowers, number of pods, pod size and number of seeds. This could be attributed to the beneficial effect of Zn by minimizing premature floral abscission, increasing pollen fertility and enhancing activity of stigmatic esterase. Maximum improvement in seed yield was observed in pea plants given foliar spray of 0.5% ZnSO4 at bud initiation. Foliar application of Zn improved not only the boldness and vigor of seeds but also the quality of the seeds in terms of carbohydrates (sugars), protein (albumins, globulins, glutenins and prolamins) and seed Zn content. The present study suggests that foliar application could be an effective strategy in biofortifying legumes with Zn to produce seeds of high nutritional quality.