Predicting wheat yield under irrigation stress at grain growth stage in south delta region [electronic resource].

Includes reference.

A field experiments were carried out at Benba, Qalyoubia Governorate in 2004/2005 and 2005/06 growing seasons to stody the effect of two wheat varieties (Sabka 93 and Giza 168) and five treatments (control, skipping irrigation at milk stage, skipping irrigation at milk stage together with application of MgCo3 skipping irrigation at maturity stage. skipping irrigation at maturity stage with and application of Mgco,) on wheat yield and its components. Results showed there was significant difference between Sakba 93 and Giza 168 for the studied characters. except for number of spikes/m2 in the second season. Results also indicated that irrigation treatments bad significant effect on all the studied characters in both seasons, except for grain weight/spike in the second season and crop index and harvest in both seasons. Further more, all studied characters were decreased as a result of skipping irrigation either at grain milk stage or at grain maturity stage. Sakba 93 was more tolerant to water stress during grain growth than Giza 168. Moreover, skipping irrigation at grain milk stage decreased yields more than skipping inigation at finai maturity stage for both varieties in the two seasons. The application of MgCo, reduced yield losses, especially for Giza 168. Results also indicated that there wasa highly significant positivecorrelation between grain yieldand plant height, numberof sipkes/m, 100 grain weight, harvest index, grain weight! spike and biological yield under all treatments. Plant height was positively correlated with straw yield and negatively correlated with straw yield under the application of .MgCo, antitranspirationagent Simple correlation analysis betweenplant attnbutes and weather parameters indicatedthat in the stage from planting to tiIlering, both air temperature and soil temperaturewere positively correlatedwith grain and straw yields and yield components. Whereas, in the stages from planting to anthesis and from planting to physiological maturity, yields and its components were negatively correlated with either air temperature or soil temperature. Results of the regression analysis showed that either air temperature or soil temperature couldbe a good predicator of grain and straw yield Further more, the most important macro and micro climatic factors were air and soil temperatures, relative humidity, variety, irrigation and length growth season.

Summary in Arabic.

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