الفهرس 
Introduction
Chemical control of stem rustOnly 14 pages are availabe for public view
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Abstract
Objectives: 1- The identification of the dominant races in certain northern provinces of Egypt. 2- Postulation of seedling stem rust resistance genes (Sr’s) in the tested wheat cultivars in the greenhouse. 3- Determination of the effectiveness of the Stem rust resistance genes at seedling and adult stages. Evaluation of 41 wheat cultivars against stem rust in adult stage in two locations. 5- Reduction of yield component in ten wheat cultivars due to stem rust infection. 6- Chemical control of stem rust . Methods & results A total of 44 and 47 physiologic races( race-groups) derived from ( 80 and 122 ) samples of stem rust were identified through two successive seasons i.e. 2008/2009 and 2009/2010. TR- race group conformed ( 8.3%) followed by TT- (6.7%) during 2008/09. Likewise, TT- recorded (16.7%) followed by TS- (11.8%) and TK- (5.9%) during 2009/010. . Stem rust genes (Sr’s) i.e., 31. PL, 6 and 9g 31, 29, (21+9g), (33+5) were considered effective genes for stripe rust at seedling stage. 3. Stem rust genes i.e., Sr7a and Sr (33 + Sr5 ) were postulated in cvs. i.e. Sakha 69 and Sids 12. For evaluation of some wheat varieties at adult stage during two seasons. a) In the first season 2008-2009 in Nubariya, 18 cv proved to have high level of partial resistance, however only 4 showed low level of partial resistance. 10 cvs rated 0 and cvs rated resistant. At Sakha during the same season 8 cvs rate (o), 16 cvs. was rated (R), 8 cvs proved to have HLPR and 9 exhibited (LLPR). b) During the second season viz 2009/010. The obtained results indicated that 3 cvs rated (R), 31 rated (HLPR) and 7 showed (LLPR) in Nubraiya. In Sakha 21 cvs rated o, - rated R, 16 showed (HLPR) and 4 showed (LLPR). Conclusion A total of 44 and 47 physiologic races( race-groups) derived from ( 80 and 122 ) samples of stem rust were identified through two successive seasons i.e. 2008/2009 and 2009/2010. TR- race group conformed ( 8.3%) followed by TT- (6.7%) during 2008/09. Likewise, TT- recorded (16.7%) followed by TS- (11.8%) and TK- (5.9%) during 2009/010.