AUTHOR=Li Mingzhu , Yuan Yuanyuan , Ni Fei , Li Xingfeng , Wang Honggang , Bao Yinguang 

TITLE=Characterization of Two Wheat-Thinopyrum ponticum Introgression Lines With Pyramiding Resistance to Powdery Mildew

JOURNAL=Frontiers in Plant Science

VOLUME=13

YEAR=2022

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2022.943669

DOI=10.3389/fpls.2022.943669

ISSN=1664-462X

ABSTRACT=<p>Powdery mildew is one of the most devastating foliar diseases in wheat production. The wild relative <italic>Thinopyrum ponticum</italic> (2<italic>n</italic> = 10<italic>x</italic> = 70) has been widely used in wheat genetic improvement due to its superior resistance to both biotic and abiotic stresses. In the present study, two wheat-<italic>Th. ponticum</italic> introgression lines named SN0293-2 and SN0293-7 were developed from the progenies of a cross between the octoploid <italic>Trititrigia</italic> SNTE20 and common wheat, including the elite cultivar Jimai 22. They had a novel powdery mildew resistance gene (temporarily named <italic>PmSN0293</italic>) putatively from <italic>Th. ponticum</italic> pyramided with <italic>Pm2</italic> and <italic>Pm52</italic>, exhibiting excellent <italic>Pm</italic> resistance at both the seedling and adult stages. Sequential GISH-FISH detected no signal of <italic>Th. ponticum</italic> in these two lines but a pair of T1BL·1RS in SN0293-2. Chromosomal structural variations were also observed obviously in SN0293-2 and SN0293-7. Through the Wheat 660K SNP array, 157 SNPs, 134 of which were on 6A, were found to be specific to <italic>Th. ponticum</italic>. Based on the data combined with DNA re-sequencing, seven specific markers, including one CAPS marker on 2B and six CAPS and Indel markers on 6A, were developed, confirming their wheat-<italic>Th. ponticum</italic> introgression nature. Furthermore, the two lines displayed positive plant height and produced more kernels and higher 1,000-grain weight. Excellent resistance with desirable agronomic traits makes them valuable in wheat breeding programs.</p>