Khodadad Mostafavi - Department of Agronomy and Plant Breeding, Karaj Branch, Islamic Azad University, Karaj, Iran
Rajab Choukan - Seed and Plant Improvement Institute, Karaj, Iran
Mohammad Taeb - Department of Agronomy and Plant Breeding, Science and Research Branch, Islamic Azad University,Tehran, Iran
Eslam Majidi Heravan - Agriculture Biotechnology Institute, Karaj, Iran

This research was aimed to classify Iranian maize inbred lines in heterotic groups and to identify theirheterotic patterns. Fourteen maize inbred lines were crossed in a diallel scheme without reciprocals.Parents and their 91 F1 hybrids were evaluated in a randomized complete block design with threereplications for two years (2007, 2008) in Karaj, Iran. Analysis of variance was performed followingmethod 2 of Griffing’s model 1. GGE biplot model was employed to extract the interaction amonglines and testers. The estimates of specific combining ability (SCA) were bigger than the analogousestimates for the general combining ability (GCA), indicating the major influence of dominant geneson the expression of grain yield. Hybrids with higher grain yield represented successful combinationof parental lines for the expression of heterosis. The best heterotic patterns were "Lancaster Sure Crop(LSC) × Lines", and "Reid Yellow Dent (RYD) × Lines, both extracted from CIMMYT originatedmaterials" and "LSC × Lines extracted from Late Synthetic". The results in heterotic patterns obtainedby biplot mostly are in accordance with those of using Grifing’s method.

Zea mays L., Combining ability, Griffing’s model, Heterotic group, Heterotic pattern, GGE biplot