پاسخ عملکرد و اجزای عملکرد چهار هیبرید ذرت دانهای با مقاومت روزنهای متفاوت به تنش خشکی

This study was conducted in order to assess the stomata resistance response, transpiration volume for canopy temperature regulation and leaf rolling under drought stress condition for some new hybrids of maize. The experiment was laid out as a factorial design based on randomized complete block with three replications, in 2015 and 2016, at Seed and Plant Improvement Institute, Karaj. Three Irrigation levels include Irrigation after 60, 90 and120 mm cumulative evaporation from evaporation pan class A, and four hybrids include KSC 703, KSC704, KSC705 and KSC706 were considered as the factors. The lower stomata resistance and canopy temperature were obtained in KSC 706 which had no leaf rolling in vegetative stage even under heat condition at noon. Grain weight was lower in KSC 706 in comparisons to other hybrids under mid and severe drought stress. The maximum and minimum of grain yield were obtained under normal irrigation and severe drought stress condition with average 7.64 and 3.34 ton/ha respectively. There were no significant difference in grain yield of different hybrids, but the highest grain moisture was obtained from KSC 706 with average 17.61%. Based on this experiment, KSC 706 may be sensitive to drought stress due to opening of the stomata and wasting moisture in environment around root zone via transpiration, so it is not recommend for the areas where there are limitation in irrigation water. [ABSTRACT FROM AUTHOR]