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Nine Tibetan weedrace, 9 Xingjiang rice wheat and 14 Yunnan hulled wheat accessions were evaluated for the variability of HMW-glutenins and gliadins. Higher variability was observed for both HMW-glutenins and gliadins in Tibetan weedrace and Xingjiang rice wheat, while lower variability was observed in Yunan hulled wheat. There were 4 HMW-glutenin and 9 gliadin patterns in 9 Tibetan weedrace accessions, 5 HMW-glutenin and 8 gliadin patterns in 9 Xingjiang rice wheat accessions, and 3 HMW-glutenin and 8 gliadin patterns in 14 Yunnan hulled wheat accessions. In Xinjiang rice wheat, one accession (i.e. Daomai 2) carried subunits 2.1 + 10.1 encoded by Glu-D1, which is very rare in common wheat.

On day 21, total germination percentages of threshed seeds of Ae. tauschii ranged from 0.0 to 92.6, indicating a large variation in preharvest sprouting tolerance. Out of 46 Ae. tauschii accessions, seven had a germination index lower than ten, which indicates good tolerance to preharvest sprouting and usefulness for common wheat (Triticum aestivum L.) improvement. The variety tauschii showed a germination percentage and a germination index much higher than that of var. strangulata. Furthermore, the tough and tenacious glumes of Ae. tauschii also had an effect on tolerance to preharvest sprouting.

Stripe rust is one of the most serious diseases of wheat in China. Two new stripe rust physiological strains CYR30(Inter. name: 175 E 191) and CYR31(Inter. name: 239 E 175) have become the dominant and epidemic physiological strains since 1994 in China. Resistance to these strains of 48 Ae. tauschii accessions was evaluated at the seedling and adult stages. Out of 48, 28 accessions displayed seedling and adult resistance. All of the Chinese Ae. tauschii accessions were susceptible at seedling and adult stages. Seedling resistance was highly related to adult resistance in Ae. tauschii. The new genetic resources of resistance to CYR30and CYR31could be incorporated into commercial wheat varieties for wheat resistance breeding by direct hybridization.

The crossability percentages of 131 landraces of wheat (Triticum turgidum L.) native to Sichuan, Shaanxi, Gansu and Xinjiang provinces of China with rye (Secale cereale L.) were tested. 45 landraces showed crossability percentages higher than 5% with 5 landraces expressing crossability percentages over 60%. The geographical distribution of crossability of these tetraploid wheat landraces was reported. Some utilization of high crossability resources was also discussed.