AUTHOR=Ren Jing , Chen Liang , Liu Jian , Zhou Bailing , Sha Yujie , Hu Guodong , Peng Junhua 

TITLE=Transcriptomic insights into the molecular mechanism for response of wild emmer wheat to stripe rust fungus

JOURNAL=Frontiers in Plant Science

VOLUME=14

YEAR=2024

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2023.1320976

DOI=10.3389/fpls.2023.1320976

ISSN=1664-462X

ABSTRACT=<sec><title>Introduction</title><p>Continuous identification and application of novel resistance genes against stripe rust are of great importance for wheat breeding. Wild emmer wheat, <italic>Triticum dicoccoides</italic>, has adapted to a broad range of environments and is a valuable genetic resource that harbors important beneficial traits, including resistance to stripe rust caused by <italic>Puccinia striiformis</italic> f. sp. <italic>tritici</italic> (<italic>Pst</italic>). However, there has been a lack of systematic exploration of genes against Pst races in wild emmer wheat.</p></sec><sec><title>Methods</title><p>Genome-wide transcriptome profiles were conducted on two wild emmer wheat genotypes with different levels of resistance to (<italic>Pst</italic> (DR3 exhibiting moderate (<italic>Pst</italic> resistance, and D7 displaying high (<italic>Pst</italic> resistance). qRT-PCR was performed to verify findings by RNA-seq.</p></sec><sec><title>Results</title><p>A higher number of DEGs were identified in the moderately (<italic>Pst</italic>-resistant genotype, while the highly (<italic>Pst</italic>-resistant genotype exhibited a greater enrichment of pathways. Nonetheless, there were consistent patterns in the enrichment of pathways between the two genotypes at the same time of inoculation. At 24 hpi, a majority of pathways such as the biosynthesis of secondary metabolites, phenylpropanoid biosynthesis, phenylalanine metabolism, and alpha-Linolenic acid metabolism exhibited significant enrichment in both genotypes. At 72 hpi, the biosynthesis of secondary metabolites and circadian rhythm-plant pathways were notably and consistently enriched in both genotypes. The majority of (<italic>WRKY, MADs </italic>, and  <italic>AP2-ERF </italic> families were found to be involved in the initial stage of response to <italic>Pst</italic> invasion (24 hpi), while the <italic>MYB, NAC, TCP</italic>, and <italic>b-ZIP</italic> families played a role in defense during the later stage of <italic>Pst</italic> infection (72 hpi).</p></sec><sec><title>Discussion</title><p>In this present study, we identified numerous crucial genes, transcription factors, and pathways associated with the response and regulation of wild emmer wheat to <italic>Pst</italic> infection. Our findings offer valuable information for understanding the function of crucial <italic>Pst</italic>-responsive genes, and will deepen the understanding of the complex resistance mechanisms against <italic>Pst</italic> in wheat.</p></sec>