Peer review

Peer-review: Yes - Open Access: Yes|http://science.thomsonreuters.com/cgi-bin/jrnlst/jlresults.cgi?PC=MASTER&ISSN=0191-2917

High-yielding durum wheat (Triticum turgidum) cultivars, derived from the CIMMYT (International Maize and Wheat Improvement Center) germ plasm, are grown on approximately 40% of the global durum wheat area. Because of the lack of information on their genes for resistance to leaf rust, crosses in a diallel arrangement (without reciprocals) were made among nine resistant CIMMYT-derived durums and the accession DW7276, which is susceptible to Mexican Puccinia recondita f. sp. tritici pathotype BBB/BN. Mexican durums were also crossed with the adult-plant resistant land race cultivar Iumillo. Inheritance of resistance was investigated in seedlings and/or adult plants of F1 hybrids, F2 populations, and F3 lines. A common, partially dominant gene confers seedling resistance in Altar 84, Carcomun, Morus, and Totanus. This gene alone does not confer an acceptable level of adult-plant resistance; however, it interacts in an additive manner with two additional partially effective adult-plant genes. Two additive genes also confer adult-plant resistance to Mexicali 75, Yavaros 79, Diver, Kingfisher, and Somorguho. At least one adult-plant gene is common in each resistant parent. However, transgressive segregation in the F2 and F3 generations for reduced or increased adult-plant leaf rust severity indicates genetic diversity. CIMMYT durums and worldwide-resistant Iumillo carry common adult-plant resistance, which could be of a durable nature.

Global Wheat Program

Text in English

R93ANALY|WP|3

INT0610