Assessment of Yield Stability and Adaptability of Parental Inbred Lines and F1- Hybrids of Grain Maize (Zea mays L.) Using AMMI Analysis

This study was carried out to identify the yield stability and adaptability of the grain maize genotypes (parental inbred lines, F1-hybrids and check varieties), using Additive Main Effects and Multiplicative Interaction (AMMI). A field experiment was executed during the winter and summer seasons of 2009 and 2010 at two locations, Shambat and Elrawakeeb, Sudan. A split-plot design with three replications was used to layout the experiment. The inbred lines and their F1-hybrids were evaluated in the field under normal irrigation and water-stress conditions. The results showed that, highly significant differences were detected among genotypes, environments and for G×E interaction, indicated differential performance of genotypes over environments. Considering mean grain yield, and the Linear Regression parameters bi and S2d values jointly, the F1-hybrids 160×2, 160×3 and 6×3 gave above average mean of grain yield/ha and were most stable for grain yield/ha. AMMI analysis differentiated the genotypes (parental inbred lines and F1-hybrids), based on their grain yield, into different adaptation pattern and stability. Based on AMMI analysis, the F1- hybrids 66y×6 and 6×3 were highly stable with considerable high yield and adapted to favorable environments. However, the F1- hybrids 160×66y and 160×3 exhibited the highest mean grain yield/ha (4.1 tons and 3.5 tons, respectively), with slightly low interaction scores, hence they are regarded as superior hybrids.