Characterization of two leaf rust-resistant Aegilops tauschii accessions for the synthetic wheat development

Abstract

Aegilops tauschii (Ae. tauschii) is a diploid (2n = 2x = 14) wild grass species, which has been reported as the progenitor of hexaploid wheat (Triticum aestivum) with D-genome. In this study, 68 Ae. tauschii accessions with diverse geographical backgrounds were investigated for their resistance to infection by the leaf rust fungi Puccinia triticina. Two Ae. tauschii accessions that exhibited hyper-resistance to leaf rust at both seedling and adult stages were identified. Utilizing two susceptible Ae. tauschii ecotypes and keumkang, a common Korean wheat cultivar known to be susceptible to leaf rust, as the negative control, further investigations were conducted for understanding the mechanism underlying immunity to leaf rust disease of these two resistant accessions. Resistant accessions displayed the increased β-1,3-glucanase activity to prevent fungal penetration and the better peroxidase activity to cope with leaf rustinduced oxidative stress. Moreover, transcriptional analyses reveal the important role of the LRR receptor-like serine/ threonine-protein kinase FLS2 (lrr) to the disease resistance of the two ecotypes. Ae. tauschii is a remarkable genetic source, especially for abiotic and biotic stress resistance genes, as the plant is known for its wide-ranging geographical habitat and adaptability to different environments. This, combined with the fact that Ae. tauschii and wheat share a close evolutionary relationship, is indicative of the immense benefit of using Ae. tauschii as a material for improving the quality of synthetic wheat. Our aim was to identify and evaluate the strongest Ae. tauschii contenders for breeding leaf rust-resistant synthetic wheat.

Unravelling complex molecular mechanisms in pine with genome-wide association analysis and gene co-expression networks

“…The correlation of RR markers found in the GWAS with the NRT1/PTR FAMILY 2.10 protein-associated gene and with chlorophyll ab protein type I has already been reported in the context of transcription repression in response to leaf rust infection 75 . In addition, some mechanisms that include stress and defence responses, such as ubiquitin-dependent protein catalysis activities, have been found for nine genes correlated with the rust response in the Pel network.…”

Variability in Physiological Traits Reveals Boron Toxicity Tolerance in Aegilops Species

“…Aegilops have been extensively identified or utilized for different biotic stress conditions, including powdery mildew resistance (Tang et al, 2018), cereal cyst nematodes (CCN) resistance (Ali et al, 2019), leaf rust (Millet et al, 2014;Lee et al, 2020;Rani et al, 2020), stem rust (Yu et al, 2015;Edae et al, 2016;Huang et al, 2018;Olivera et al, 2018), stripe rust (Millet et al, 2014), green bug (Crespo-Herrera et al, 2013), and hessian fly (Martin-Sanchez et al, 2003;Kishii, 2019), and fusarium head blight (Brisco et al, 2017). Other than biotic stress, the utility of Aegilops species for abiotic stress, including drought (Djanaguiraman et al, 2019;Suneja et al, 2019), heat (Awlachew et al, 2016;Green et al, 2018), salinity stress (Kiani et al, 2015), has also been determined.…”

Comparative transcriptome analysis of two contrasting resistant and susceptible Aegilops tauschii accessions to wheat leaf rust (Puccinia triticina) using RNA-sequencing

“…To avoid yield losses and reduced quality, host resistance is both cost-effective and environmentally safe 7 . Therefore, developing rust-resistant wheat varieties is undoubtedly an important task for feeding the world’s ever-increasing population 8 – 10 .…”