TESTING OF INTRODUCED GERMPLASM OF MAIZE BY LINE X TESTER MATING SYSTEM: II- PHENOTYPIC TRAITS

Abstract

Field experiment was conducted at the field of Field Crops Sci., College of agric. Univ. of Baghdad. Ten inbred lines introduced from Italia were tested in Iraqi central environments for general and specific combining ability by using Line x tester mating method. Planting date was on spring and fall of 2009, selfing was used to increase homozygosity. On spring season / 2010 seeds were planted, at anthesis crossing between inbreds and tester was done. On fall season/ 2010 for crosses and parents using RCBD with four replications to evaluate and estimate some genetic parameters. The results of statistical analysis for these parents and their crosses were highly significant differences for all traits: Genetic analysis shows superiority the inbred L3 in gca for plant and ear height, and no. of leaves. The cross L1 × t8 gave high no. of rows and longer ear (20.8cm and 18.8 cm ), and gave highly positive hybrid vigor for no. of rows and ear length ( 34.19 row and 11.24 cm ) and high no. of leaves and gave high sca for no. of rows and leaves . Additive variations for inbreds were more than testers for all traits except no. of leaves and ear length, so it's more than non additive gene action. The σ2gca for inbreds was more than testers for plant and ear height, leaves area and no. of rows. σ2gca/ σ2sca were less than one for all inbreds and testers traits except no. of leaves and ear length for testers. Some traits controlled by over dominance where average degree of dominance was more than one, while other traits controlled by partial dominance where ā was less than one. We can conclude the possibility of using superior inbrds to produce hybrids or use selection for it and produce synthetic variaties .