الفعل الجيني للتبكير و حاصل بعض أصناف و هجن القطن تحت فترتين للري

الملخص EN

A field experiment was carried out during 2010-2011 at the experimental field of Crop Science Dept.-College of Agriculture-Abu-Graib.

This was to estimate of combining ability and type of gene action in inheritance of earliness and seed cotton yield for genotypes under water stress conditions and estimate of hybrid vigor.

Five varieties of cotton included Cocker-310, Dise, Macneer, Marsoomi-5 and Rabeaa-122 were crossed, during the season of 2010 using half diallil.

The traits for 10 single crosses and 5 parents were tested during 2011 using RCBD design under split plot arrangement with three replications, irrigation treatments occupied main plot included irrigation weekly and at two weeks and sub plot included 15 genotypes.

Significant differences were found among genotypes in all traits studied.

The crosses cocker-310 X Rabee122 and Marsoomi5 X Rabee122 were gave highest positive hybrid vigor (22.06 and 21.94 % respectively) in seed cotton yield in irrigation at two weeks.

The cross Marsoomi5 X Macneer gave higher hybrid vigor in earliness (4.65 %).

The variances due to GCA and SCA were significant for traits studied accept no.

of monopodia.

This indicated that both additive and non-additive gene action were responsible for the investigated characters.

The parent Macneer had highest GCA effect for seed cotton yield, no.

of days to first open flower and no.

of days to first open ball, the cross Cocker-310 X Rabee122 had highest SCA in seed cotton yield and cross Marsoomi5 X Rabee122 in earliness traits.

It can be conclude that earliness traits were effected by non-additive gene action so can use hybridization following to selection to find early and high yield crosses.