Study of Quantitative Characteristics Related to Resistance to European Corn Borer (Ostrinia nubilalis Hbn) in Maize Hybrids

To evaluate the resistance of nine hybrids of corn to European corn stem borer, an experiment was conducted in Moghan Agricultural Research Center in Parsabad during the cropping season in 2005, using a randomized complete block design with four replications. Ten randomly selected plants in each plot were evaluated for different traits related to the activities and loss caused by the pest in three growth stages of maize including stage 7-8 leaves (pest first generation), tassel appearance stage (pest second generation) and seed maturity stage (pest third generation). The results showed that maize hybrids differed significantly for different traits such as stalk tunnel length, plant height, stalk breakage percentage, number of holes made by the pest, diameter of ear husk and grain yield. Two hybrids K3047/2×MO17 and K74/1×Mo17 having the shortest stalk tunnel length, lower percentage of stalk breakage, lower number of holes and higher grain yield exhibited the best characteristics of resistance against the pest damage, compared to the other hybrids. Two other hybrids, 20NS×K19 and K74/1×K19 showed lower resistance characteristics based on the measure of those traits. The remaining hybrids responded differently to the measured traits