Grain yield stability of promising grain maize (Zea mays L.) hybrids in different regions of Iran

To investigate the response of new maize hybrids to different environmental conditions and determine their grain yield stability, an experiment was conducted using eight maize hybrids in a randomized complete block design with three replications in six locations in 2016. Due to the significant hybrid × environment (G × E) interaction, stability analysis was performed using two multivariate methods, AMMI and GGE-biplot. The results of the AMMI model showed that only the first principal component (AMMI1) was significant and accounted for 72.52% of the G×E variation. Based on AMMI model statistics (SPCA1 and ASV), the hybrids No. 1 ( KSC715B) and 5 (KSC706) were selected as the highest stable hybrids. The results of stability anlaysis by GGE-biplot procedure showed that 83.32% of the total grain yield variation was explained by the first and second component of GGE-biplot and the hybrids No. 1 (SC715B) and 7 (SC703) were identified as the hybrids with higher stability. In total, based on grain yield and the results of stability analysis using these two methods, the hybrids No. 7 (SC703) and 1 (SC715B) with grain yield of 13.16 and 12.82 t/ha, respectively, were identified as the most stable hybrids with most high yielding and due to high general adaptability, cab be cultivated in different regions of Iran. Also, biplot of correlation among environments revealed that Moghan, Shiraz and Kerman as well as Ghaemshahr, Kermanshah and Karaj, were very close to each other and were similar in ranking the studied hybrids. Considering high dicreament power of hybrids in Shiraz, Kerman, Karaj and Ghaemshahr regions and in order to save the costs of future experiments, it is recomanded that the experiments be carried out in these four regions instead of six.