الفهرس 
Introduction
earliness and drought resistance in crop plantsOnly 14 pages are availabe for public view
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Abstract
Genetic studies on some economical characters in wheat. The effects of drought stress on the components of the genetic variation for earliness, grain yield per plant, plant height and spike length in wheat (Triticum aestivum L.) were investigated using a 6—parent diallel cross among four local and two exotic cultivars at F1 and F2 generations grown in stressed sandy soil and non-stressed clay soil environments. The possible relationships between drought susceptibility and both earliness and grain yield were also examined.
The results obtained could be summarized as follows:
1— Earliness:
Drought stress enhanced the flowering of the wheat plant. The sowing to flowering period of the parents, the F11s and F2 hybrids was reduced under stress by about 10 days, on average. Additive and non—additive gene effects were involved in the control of this trait in both environments. The additive gene effects were more important in the control of this trait. The Wr/Vr analysis revealed that over—dominance was operating under the favourable conditions whereas complete dominance was detected under drought stress. The order of dominance of the different parents was reversed under drought. Broad—sense herita— bility was estimated to be 0.87 in the favourable environ— ment, and 0.91 under stress while the narrow—sense H