IJAER

International Journal of Agriculture and Environmental Research™

ISSN 2455-6939

Title:
IMPROVING PRODUCTIVITY AND GRAIN NUTRITIONAL QUALITY OF WHEAT (Triticum aestivum) UNDER DROUGHT STRESS CONDITION BY COMBINED NPK FERTILIZATION

Authors:
Mohammad Safar Noori, Hirofumi Saneoka

Abstract:
Drought stress is a major threat that retards plant growth, reduces grain yield and affects grain quality. The present study was conducted to ascertain the effect of combined application of nitrogen (N), phosphorus (P) and potassium (K) fertilizers on productivity, and nutritional quality of wheat under drought stress conditions. Wheat cultivars Minaminakaori and Lalmi-2 were grown in pots in a greenhouse, and subjected to 3 levels of NPK fertilizer applications. Then the plants were exposed to 2 levels of drought stress and well-irrigated control at grain filling stage. The result of this study indicated that drought stress significantly decreased grain yield, grain starch content, and water-soluble pentosan content, but increased grain crude protein content, total pentosan content, and phytate phosphorus content of both cultivars. Lalmi-2 exhibited a greater tolerance to drought conditions, by higher grain yield, and higher total K and starch contents under both well-irrigated and drought stress conditions than Minaminakaori, while Minaminakaori recorded higher grain mineral concentration, crud protein, total pentosan, water-soluble pentosan and phytate phosphors content than Lalmi-2. It was suggested that increase in rate of NPK fertilization could ameliorate the adverse effects of drought stress and enhance plant productivity, and concentrations of minerals, crude proteins and water-soluble pentosan in the grain under drought stress conditions. Besides applying higher rates of NPK fertilizers, it is suggested that use of fertilizer responsive and drought-tolerant genotypes such as Lalmi-2 will be beneficial to minimize the risk of yield loss due to drought stress.

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