Evaluation of selected promising bread wheat lines in late generations under two sowing dates

الملخص EN

Five parents and their derived F₅ families (12 families) and new check variety Sakha 95 were evaluated under two sowing dates, optimum sowing (OS) and late sowing (LS) dates for earliness, yield and yield components.

The study was laid out in RCBD experiment in four replications in the experimental farm at Sakha Research Station, KafrElsheikh Governorate.

The analysis of variance showed the presence of highly significant differences between years, sowing dates and genotypes under study.

Interactions between all studied characteristics were also significant except for No.

of kernels spike^-1 and No.

of spikes m^-2.

Reductions in grain yield and its components were observed in the first season compared to the second season due to climatic conditions.

Likewise, the values of the characteristics at the late planting date were less than the ones at the recommended date due to the effect of high temperatures at the end of the season.

For the characteristics of the resistance to the rust, three families showed resistance to the three rusts in the two seasons, as well as on the two sowing dates.

Therefore, these three families can be used in breeding for rust resistance.

Family number 12 was the most tolerant to high temperatures at the end of the season after the comparative cultivar Sakha 95 and recorded the lowest percentage of decline in yield as a result of late planting, so it is recommended to plant them in the case of late planting.