Combining ability and some genetic parameters using factorial mating for some growth traits for maize

Abstract

         A field experiment was conducted in the farmer field at Al-sweria city during seasons spring. Autum 2015 and Autum 2016 - eight inbred lines of maize were introduced factorial mating design program suggested by Comstock and Robinson, four lines as males (Sy19 ,HS , Dr-C- 10 and ZP607) and females (S-165 , Sy-1 , 7MGW- and Sy-22)  were planted in spring 2015 and crossing between them , the genotypes (8 parents and 16 hybrid ) were planted in full 2015 and 2016 by using randomized complete block design with three replications to estimated combining ablitly general and specific and some genetic parameters of maize traits plant height, ear height , number of leaves, leaf area and ear length . The results were showed significatly difference between lines and hybrids , Sy-1 female parent was gave highest means 0.5196 m² of leaf area , while Sy-22 parent was gave lowest means of all traits the HS male parent was gave hight means while ZP607 was gave low .  The  hybrid (MGW-7× Dr-C-10) (S-165× SH), (Sy-1× Dr-C-10) were gave highest means , while hybrids (S-165× ZP607) , (MGW-7× ZP607) , (Sy-22× ZP607) were gave the lowest means for two seasons. The results showed general combining ability effect the Sy-1 and MGW-7 famels parent were gave desived positive effect  of general combining ability , while S-165 and Sy-22 males parent were gave negative effect , but the males parent (Dr-C-10 and SH) were gave positive effect of general combining ability while Sy-19 and ZP607 were gave negative effective . The hybrid (MGW-7× Dr-C-10) was gave best in effect of specific combining ability 133.9 and 163.0 for leaf area in two sensons . The genetic variance was highest than environmental variance , this result reflect on broad sense heritaability was recorded high value 99.7 of number leaves in the first season and 95.62% of ear hight in second season , while  the narrow sense heritability was (middle-hight) value the hight 64.5% of number leaves in firest season. The dominance degree average was higher than one of all traits ,  we conclude from this the possibility of benefinting from this the possiblity of benefinting from the superior hybrids , which gave of specific combining ability in the desired direction to produce elite genotypes next program.