Evaluation of yield and some resistance-related traits of three maize hybrids against European corn borer Ostrinia nubilalis (Hubner)

Abstract

This research was carried out to evaluate the yield and some resistance-related traits of three maize hybrids produced with B73 or Mo17 as the parents, against European corn borer, Ostrinia nubilalis (Hubner). Two separate experiments (with and without insecticide spraying) were conducted as a factorial experiment with two factors including sowing date at three levels (25th April, 10th May, and 25th May) and hybrids at three levels [KSC704 (B73 × Mo17), KSC705 (K3640/3 × Mo17), and KSC706 (K3547/4 × Mo17)] based on randomized complete block design with four replications for two years in Moghan region, Iran (39° 41′ N 47° 32′ E, with 32 m above the sea level). The results showed that KSC706 with 12.19 and 13.41 t ha−1 had the highest grain yield in non-sprayed and sprayed conditions, respectively. In sprayed conditions, KSC705 and KSC706 showed the highest net income, while in non-sprayed conditions KSC706 showed the highest net income. Overall, KSC706 showed a reduction in net income due to insecticide application, while two other hybrids showed increasing net income due to insecticide use. This achievement demonstrated that KSC706 is relatively tolerant to ECB damage and insecticide application raises the cost of grain production while did not increase the yield. In sprayed conditions, KSC705 in the first sowing date showed the longest and KSC706 in the third sowing date showed the shortest tunnel length. In both sprayed and non-sprayed conditions, KSC706 in third sowing date showed the lowest stalk breakage percentage which could candidate KSC706 as a tolerant hybrid against ECB.