Resistance to Puccinia recondita tritici in synthetic hexaploid wheats

Sixty seven elite synthetic wheats were evaluated at seedling and adult plant stages in the greenhouse and field, respectively. 77-5, a most virulent leaf rust pathotype was used in both seedling and adult plant studies. Out of 67 accessions, 40 were highly resistant at seedling and adult plant stages, while 24 synthetic hexaploid were highly resistant as adult plants and highly susceptible as seedlings. Only 3 accessions were observed to be susceptible at both the stages. A high degree of genetic variability for leaf rust resistance was observed at both seedling and adult plant stages in these synthetic wheats. The study revealed the presence of a number of genes for seedling and adult plant resistance in synthetic hexaploid wheats. These new sources of resistance could be incorporated in hexaploid wheats to diversify the existing gene pool for leaf rust.