Genetic behavior of earliness, yield and yield components in three bread wheat crosses under two sowing dates [electronic resource].

Includes reference.

The main objective of this investigation was to study the inheritance of earliness and some agronomic traits in bread wheat. The experiment was conducted at Sakha Experimental Research Station during 2003/2004 to 2005/2006 seasons. Three crosses were made used four parents differ in their maturity. Those crosses were Sakha 61/Une 2 (early x early), line 2/Giza 163 (early x late) and Giza 163/Gemmeiza 9 (late x late). Data indicated that the two involved parents in each cross were significantly different for most traits at the two sowing dates. F- test for the F2 variance showed that F2 plants were genetically different in the three crosses for all studied traits under the two sowing dates. Mean values for number of spikes/plant, number of kernels /spike and grain yield/plant under the normal sowing date were higher than the corresponding ones at early sowing date. Meanwhile, mean value for kemel weight was higher at early sowing date than that of the normal one. Additive and dominance genetic effects played together a great role in the inheritance of aU studied traits under the two sowing dates. However, . the additive genetic effect was more important. Moreover, additive x additive and dominance x dominance epistatic effects were important in all studied traits under the two sowing dates. Heritability estimates were high for most studied traits under the two sowing dates in both broad and narrow senses. Therefore, the expected genetic advance was moderate or high for most studied traits under the two sowing dates.

Summary in Arabic.

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