Haustoria – arsenals during the interaction between wheat and Puccinia striiformis f. sp. tritici

Abstract

SummaryAs an obligate parasite, Puccinia striiformis f. sp. tritici (Pst) forms haustoria to obtain nutrients from plant cells for development, and these structures are essential for pathogen survival. To better understand the contribution of haustoria to the interactions with the host plants, we isolated haustoria from susceptible wheat leaves infected with Pst race CYR31 and sequenced their transcriptome as well as those of urediospores and germ tubes, and compared the three transcriptomes. A total of 3524 up‐regulated genes were obtained from haustoria, of which 73 genes were related to thiamine biosynthesis, glycolysis and lipid metabolic processes. Silencing seven of the genes reduced the growth and development of Pst in wheat. More interestingly, 1197 haustorial secreted proteins (HASPs) were detected in haustoria, accounting for 34% of the total proteins, indicating that these HASPs play important roles in haustorium‐mediated pathogenic progression. Furthermore, 69 HASPs were able to suppress Bax‐triggered programmed cell death in tobacco. Additionally, 46 HASPs significantly reduced callose deposition in wheat using the type III secretion system. This study identified a large number of effectors through transcriptome sequencing, and the results revealed components of metabolic pathways that impact the growth and colonization of the pathogen and indicate essential functions of haustoria in the growth and pathogenicity of Pst.

Role of Fungicide Applications on the Integrated Management of Wheat Stripe Rust

“…This pathogen possesses the ability to generate several resistance-breaking races or pathotypes that carry different race-specific avirulence or effector coding genes that make them more specialized in infecting different wheat cultivars. Pst genomes are highly heterozygous and encode several effectors (Chen et al, 2009(Chen et al, , 2010Cantu et al, 2013;Zheng et al, 2013;Cuomo et al, 2017;Kiran et al, 2017;Schwessinger et al, 2018;Xu et al, 2020). This genetic characteristic results in rapid emergence of virulent Pst races.…”

Genome-Wide Identification of Effector Candidates With Conserved Motifs From the Wheat Leaf Rust Fungus Puccinia triticina

“…tritici, Pst), stem rust (Puccinia graminis f. sp. tritici, Pgt), and leaf rust (Cantu et al, 2011;Duplessis et al, 2011;Zheng et al, 2013;Kiran et al, 2016;Xu et al, 2020). The draft genome of the wheat leaf rust fungus has greatly facilitated efforts to identify genes associated with leaf rust infection (Kiran et al, 2016).…”

Revealing Differentially Expressed Genes and Identifying Effector Proteins of Puccinia striiformis f. sp. tritici in Response to High-Temperature Seedling Plant Resistance of Wheat Based on Transcriptome Sequencing

“…In the previous studies, PEC6, Pst_8713, PstGSRE1, and PSTha5a23 have demonstrated suppression of plant PTI and ETI as a type of effector proteins of Pst (22)(23)(24)(25). Sixty-nine of 91 haustorial secreted proteins of Pst have been proved to suppress PCD in tobacco (53). Moreover, it has been proved that effectors of bacteria, oomycetes, and fungi can suppress PTI-associated PCD and callose deposition, as well as ETI-associated ROS accumulation (22,26,54,55).…”