Characterization of Wheat Monogenic Lines with Known Genes and Wheat Lines with Resistance to the Ug99 Race Group for Resistance to Prevalent Races of f. sp. in China.

Wheat stem rust, caused by f. sp. , is one of the most serious fungal diseases in wheat production, seriously threatening the global supply of wheat and endangering food security. The present study was conducted to evaluate wheat monogenic lines with known genes to the most prevalent f. sp. races in China. In addition, wheat lines introduced from the International Maize and Wheat improvement Center (CIMMYT) with resistance to the Ug99 race group were also evaluated with the prevalent Chinese f. sp. races. The monogenic lines containing , , , , , , , , , and were effective against races 21C3CTTTM, 34C0MRGSM, and 34C3MTGQM at both seedling and adult-plant stages. In contrast, monogenic lines containing , , , , , , , , , , , , , , , , and were highly susceptible to these races at both seedling and adult-plant stages. Lines with , , , , , , , , , , , , , , , and were resistant to one or more of the tested races. Among the 123 CIMMYT lines, 38 (30.9%) showed varying levels of susceptibility to Chinese f. sp. races. The results should be useful for breeding wheat cultivars with resistance to stem rust.