Effect of drought stress on grain yield and yield components on forage corn hybrids
Subject Areas : Journal of Plant Ecophysiology
M. Hajibabaei
1
(گروه زراعت و اصلاح نباتات، واحد ورامین- پیشوا، دانشگاه آزاد اسلامی، ورامین، ایران)
F. Azizi
2
(موسسه تحقیقات اصلاح و تهیه نهال و بذر کرج، کرج، ایران)
Keywords: Yield, Corn, Hybrid, Irrigation Regimes, drought tolerance indices,
Abstract :
In order to study the effect of drought stress on grain yield and yield components on some forage corn hybrids, an experiment was conducted at the experimental field of Seed and Plant Improvement Institute of Karaj, in 2009. The experiment was carried out using split-plot in a randomized complete block design (RCBD) with three replications. Main plots consisted of three levels of irrigation regimes (irrigation after 70, 100 and 130 mm evaporation from evaporation pan class A) and sub-plots included 14 new corn hybrids. The results showed that different between hybrids were significant for 1000-kernel weight, number of kernel per row, number of kernel row per ear and ear length. No significance differences were observed between hybrids for kernel yield, total number of kernels per ear and ear diameter. Also, all of the traits except number of row per ear decreased under drought stress conditions. Interaction between irrigation regimes and hybrid were significant for ear length. Increasing in drought stress resulted in decreasing of kernel yield in 31%. Regarding to the correlation of traits can be concluded that the ear length, ear diameter, number of grain per row, number of row per ear, grain weight, grain yield could have a significant impact in with changing in soil moisture deficiency. In addition to significant correlation under normal and mild drought stress conditions MP, GMP, STI were determined as the best indices. Under normal and drought stress TOL and SSI were the best indices for introduce drought tolerant maize hybrids. Hybrids KSC700, KLM77029/8-1-2-3-2-3×MO17 and K47/2-2-1-4-1-1-1×MO17 also identified as tolerant hybrids under drought stress conditions.