الفهرس 
Effect of water stress on bread wheat
Materials and ExperimentsOnly 14 pages are availabe for public view
 |  | from | 173 |  |  |
| | | from | 173 | | |
Abstract
The current study was carried out at the Experimental Farm of El-Gemmeiza Agricultural Research Station, ARC, Egypt, in the seasons 2018/19 and 2019/20. Eight spring bread wheat promising lines (from Line 1 to Line 5) along with the commercial cultivars Sahel 1, Sids1 and Gemmeiza 9 were used as parents. The eight parents and their twenty-eight F1’s were evaluated in two separated experiments: In the first experiment (normal) the genotypes were irrigated four times after sowing irrigation (five irrigations). The second experiment (water stress) were irrigated only with one surface-irrigation, 35 days after sowing (two irrigations). This work aimed to evaluate some promising wheat lines and Egyptian cultivars, find out good general combiners and best specific combinations, select the superior crosses and study the genetic behavior of some agronomic characters under normal and water stress conditions. The studied traits were: No. of days to heading, No. of days to maturity, plant height (cm), No. of spikes plant-1, No. of grains spike-1, spike grain weight (g), 1000-grain weight (g) and grain yield plant-1 (g). General (GCA) and specific (SCA) combining ability effects were calculated using Griffing (1956) method 2 model 1. Partitioning the total genetic variance to its consistent parts: additive and dominance genetic effects were estimated using diallel analysis technique as outlined by Hayman (1954 and 1958). Graphical analysis was carried out for the studied characters, following the procedures suggested by Hayman (1954, 1958). Four water stress tolerance indices were estimated as follow: stress susceptibility index, tolerance index, stress tolerance index and yield index.