Effects of drought stress and irrigation methods on yield and yield components in two hybrids of corn (Zea mays L.)
Subject Areas : Agroecology Journal
Farzad Paknejad
1
(Assist Prof., Islamic Azad University, Karaj Branch, Iran.)
saeed vazan
2
(Assist Prof., Islamic Azad University, Karaj Branch, Iran. E-mail: farzad_paknejad@kiau.ac.ir)
jalil ajali
3
(Scientific Board of Agronomy, Islamic Azad University, Miyaneh Branch, Iran.)
mojtaba Mirakhori
4
(M. Sc. Student and member of Young Researcher’s Clup, Islamic Azad University, Karaj Branch, Iran.)
mohammad nasiri
5
(Associate Prof., Islamic Azad University, Varamin Branch, Varamin, Iran.)
Keywords: Drought stress, Grain yield, Zea mays, Irrigation methods,
Abstract :
This study was conducted to investigate the effects of drought stress and two irrigation methods on yield and yield components in two hybrid varieties of corn named: SC704 and SC647. A split-split plot experiment based on a randomized complete block design with tree replicates was used at the Agricultural Research Station of Islamic Azad University, Karaj Branch (35°43´ N latitude, 50° 56´E longitude, 1160m altitude) in 2006 and 2007. Main plots were allocated to drought treatments that were applied at 40%, 60% and 75% levels of soil moisture depletion, sub-polts to two levels of irrigation methods (irrigation of all furrows and irrigation furrows alternately) and sub-sub plots to two hybrid varieties. The results showed that drought stress had significant effects on yield and yield components and sever stress treatment (75% moisture depletion) caused 37% yield reduction. Two irrigation methods didn’t have any significant effects on grain yield, but a significant interaction effect of genotype and watre stress was observed, whereas the hybrid SC647 produced more yield in full irrigated furrows and hybrid SC704 produced more yield in the alternative irrigated furrows. Indeed, SC704 yielded more than SC647 under water deficit condition when all furrows were irrigated. There was a significant positive correlation between grain yield with biomass, grain weight (r = 0.67), grain number in plant row, grain number in plant row (r = 0.72), plant height and a negative correlation with inoculated part of cob (r = -0.76).
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