Mapping the Rice Bacterial Blight Resistance Gene Xa23 with RFLP Markers and Converting RFLP to STS Marker Distribution of Grain Hardness and Allelic Variation of Puroindoline Gene in Russian Wheat Varieties Molecular Identification and Analysis of Puroindoline Alleles in 81 Foreign Wheat Varieties Molecular Characterization of Slow-Rusting Genes Lr34/Yr18 in Chinese Wheat Cultivars Characterization of Overexpressed Bx7 Gene(Bx7OE) in Chinese and CIMMYT Wheats by STS Markers