USING STATISTICAL METHODS TO EVALUATE SOME INBRED LINES OF MAIZE UNDER DIFFERENT SOWING DATE

Abstract

GGE biplot analysis is an effective method which is based on the principal component analysis (PCA) in order to fully evaluate multi environmental yield trials (METs). Additive main effects and multiplicative interaction (AMMI) is an alternative method for assessing phenotypic stability and adaptability. In this research, data of 16 maize inbred lines were used to perform AMMI and GGE biplot analysis. These inbred lines were evaluated under four sowing dates during two successive summer seasons of 2012 and 2013. Inbred line by sowing dates table was used for performing the analysis. Based on both mean grain yield and yield stability, inbred lines Giza 603, Sids 34, Giza 629 and Giza 628 proved to be superior and also had greater mean performance among the test inbred lines. Graphic analysis was used to identify the most suitable inbred lines for each tested sowing date. Inbred lines Sids 34, Giza 629, Gemmeiza 1021, Sids 7, Giza 612, Giza 628, Giza 603, Gemmeiza 1004 and Giza 602 were identified as suitable in all sowing dates. The AMMI analysis identified the best sowing date as second sowing date D2 which had the highest PCA1 and the best 1PCA2 values. The GGE biplot graphics revealed four sowing dates were clustered into two groups in all cases Group one included sowing date 1 and 2 Group two included sowing date 3 and 4, inbred line Giza 603the best performer in all inbred lines, followed by Sids 34, Giza 629 and Giza 628. Inbred lines Giza 603, Sids 34, Giza 628, had the highest yield stability into the best sowing dates. Thus sowing date 1 and 4 are the most discriminative sowing dates. . This inbred lines intervention in the production of many commercial hybrids.