Diallel crosses and some genetic parameters for corn agronomic characters


A field trails were conducted, at the experimental field of Crop Science Department, College of Agriculture, University of Baghdad, during spring and fall seasons of 2004 and spring season of 2005. The objective of this research was to evaluate daillel crosses developed from 10 inbred lines, Bk26, Bk43, Bk25, Bk39, Bk3, Bk41, Bk65, Bk16, Bk55 and Bk11 (recommended from last research) and estimate some genetic parameters for corn ( Zea mays L) agronomic characters. Inbred lines propagated and full diallel crosses carried out. Varietal trails were conducted using Lattice Design, with four replications to evaluate single crosses, their reciprocals and parents in fall season 2004 and spring 2005.The diallel crosses, Bk39xBk3 and reciprocal crosses, Bk55xBk5, Bk39xBk43 in fall season, took up lowest period days to tasseling 50.5, 50.8 and 50.8 days , respectively , while in the spring season the daillel cross Bk43*Bk65and reciprocal Bk65*Bk26took lowest days (59.3 and 52.3 days).The shortest slinking time in fall season (52.3 days) was for daillel cross, Bk3*Bk41and reciprocal Bk43*Bk39, While in spring was 62.3 for daillel, Bk43xBk55 and reciprocal Bk39*Bk25.The daillel Bk41*Bk55 and reciprocal Bk39*Bk25 produced the tallest plants in the first season (218, 210 cm.), in the fall season the tallest plants (212, 197 cm) produced from daillel cross Bk25xBk55 and reciprocal Bk39xBk25, respectively. The plants of daillel cross Bk25xBk65, reciprocal Bk39xBk25 in the first season and daillel Bk25*Bk55, reciprocal Bk55*Bk11 in the second season produced higher ear height. The higher leaf area 0.62 m2produced from the plants of daillel cross Bk26xBk55 in fall season. The results showed importance of cytoplasmic effects and significance of general and specific combining ability in all the studied traits. The average degree of dominance more than one for daillel and reciprocal crosses in both seasons. All the studied traits under non-additive gene action.