Identification and Evaluation of Wheat- Aegilops bicornis Lines with Resistance to Powdery Mildew and Stripe Rust

• Published in: Plant disease Vol. 106; no. 3; p. 864
• Main Authors: Wang, Xiaolu, Han, Ran, Chen, Zhiwei, Li, Jianbo, Zhu, Tong, Guo, Jun, Xu, Wenjing, Zi, Yan, Li, Faji, Zhai, Shengnan, Li, Haosheng, Liu, Jianjun, Liu, Aifeng, Cheng, Dungong, Song, Jianmin, Jia, Juqing, Ma, Pengtao, Liu, Cheng
• Format: Journal Article
• Language: English
• Published: United States 01.03.2022
• Subjects: Aegilops - genetics; Chromosomes, Plant - genetics; In Situ Hybridization, Fluorescence; Plant Breeding; Plant Diseases - genetics; Triticum - genetics; FISH; Aegilops bicornis; disease resistance; agronomic traits; molecular marker
• ISSN: 0191-2917
• DOI: 10.1094/PDIS-05-21-0982-RE

Wheat pathogens, especially those causing powdery mildew and stripe rust, seriously threaten yield worldwide. Utilizing newly identified disease resistance genes from wheat relatives is an effective strategy to minimize disease damage. In this study, chromosome-specific molecular markers for the 3S and 7S chromosomes of were developed using PCR-based landmark unique gene primers for screening wheat- progenies. Fluorescence in situ hybridization (FISH) was performed to further identify wheat- progenies using oligonucleotides probes Oligo-pSc119.2-1, Oligo-pTa535-1, and Oligo-(GAA) . After establishing 3S and 7S chromosome-specific FISH markers, Holdfast (common wheat)- 3S addition, 7S addition, 3S (3A) substitution, 3S (3B) substitution, 3S (3D) substitution, 7S (7A) substitution, and 7S (7B) substitution lines were identified by the molecular and cytological markers. Stripe rust and powdery mildew resistance, along with agronomic traits, were investigated to evaluate the breeding potential of these lines. Holdfast and Holdfast- progenies were all highly resistant to stripe rust, indicating that the stripe rust resistance might derive from Holdfast. However, Holdfast- 3S addition, 3S (3A) substitution, 3S (3B) substitution, and 3S (3D) substitution lines showed high resistance to powdery mildew while Holdfast was highly susceptible, indicating that chromosome 3S of carries previously unknown powdery mildew resistance gene(s). Additionally, the transfer of the 3S chromosome from to wheat significantly increased tiller number, but chromosome 7S has a negative effect on agronomic traits. Therefore, wheat germplasm containing chromosome 3S has potential to contribute to improving powdery mildew resistance and tiller number during wheat breeding.