Markers assisted selection for multiple Stripe rust resistance genes in spring bread wheat lines
By: Naseeb Ullah, Niaz Ali, Muhammad Iqbal, Aziz-ud-Din, Azhar Hussain Shah, Inayat Ur Rahman, Habib Ahmad, Inamullah, Ghulam Muhammad Ali
Key Words: Stripe rust, Molecular markers, Spring wheat, Genetic resistance.
Int. J. Biosci. 8(3), 63-74, March 2016.
Stripe rust (yellow rust) of wheat, caused by Puccinia striiformis f. sp. tritici (Pst), is one of the most important yield limiting diseases of wheat. Although, the pathogen has overcome resistance offered by more than 90 genes and QTLs still, aggregation of resistant genes in future wheat genotypes is the most practical and efficient means of tackling the rapidly evolving virulent races of Pst. In order to stack combination of effective stripe rust resistance genes in future wheat genotypes, 99 spring wheat lines derived from the cross of Khyber-87 × Suleman-96 were screened with five closely linked PCR-based markers with stripe rust resistance genes Yr5, Yr10, Yr17 and Yr9. Out of 99 experimental lines, S19M93 and S23M41 markers revealed the presence of Yr5 gene in 86 and 70 genotypes, respectively. While, Xpsp3000 suggested presence of Yr10 gene in 66 genotypes, excluding two heterozygous lines PBS-07-60 and PBS-07-64. VENTRIUP-LN2 marker revealed that all genotypes were negative for Yr17 gene, while iag95 marker revealed presence of rye origin Yr9 gene in all genotypes. The presence of 1RS fragments may be related to the poor bread making quality in certain wheat backgrounds. Furthermore, coexistence of both Xpsp3000 and iag95 markers are indicative of the potential interstitial recombination between wheat 1BS and rye 1RS chromatin or the presence of 1RS fragments on more desirable wheat chromosomes 1A or 1D. The present work will facilitate gene pyramiding approaches against stripe rust and may be useful in future wheat improvement programs.