Diversity of Expression Patterns of Lr34 , Lr67 , and Candidate Genes towards Lr46 with Analysis of Associated miRNAs in Common Wheat Hybrids in Response to Puccinia triticina Fungus

• Published in: Current issues in molecular biology 2024-06, Vol.46 (6), p.5511-5529
• Main Authors: Spychała, Julia, Tomkowiak, Agnieszka, Noweiska, Aleksandra, Bobrowska, Roksana, Bocianowski, Jan, Sobiech, Aleksandra, Kwiatek, Michał Tomasz
• Format: Article
• Language: English
• Subjects: APR resistance; candidate genes; hybrid breeding; leaf rust; slow rusting
• ISSN: 1467-3045; 1467-3037; 1467-3045
• DOI: 10.3390/cimb46060329

Leaf rust caused by (Pt) is one of the most dangerous diseases causing significant losses in common wheat crops. In adult plants resistant to rust, a horizontal adult plant resistance (APR) type is observed, which protects the plant against multiple pathogen races and is distinguished by greater persistence under production conditions. Crucial pleiotropic slow-rust genes such as , , , and , in combination with other genes of lesser influence, continue to increase durable resistance to rust diseases. Based on our previous results, we selected four candidate genes for out of ten candidates and analysed them for expression before and after inoculation by . As part of our study, we also investigated the expression patterns of miRNA molecules complementary to and the candidate genes. The aim of the study was to analyse the expression profiles of candidate genes for the gene and the and genes responsible for the differential leaf-rust resistance of hybrid forms of the F1 generation resulting from crosses between the Glenlea cultivar and cultivars from Polish breeding companies. In addition, the expression of five miRNAs (tae-miR9653b, tae-miR5384-3p, tae-miR9780, tae-miR9775 and tae-miR164), complementary to , and selected candidate genes were analysed using stem-loop RT-PCR and ddPCR. Biotic stress was induced in adult plants by inoculation with fungal spores, under controlled conditions. Plant material was collected before and 6, 12, 24, and 48 h after inoculation (hpi). Differences in expression patterns of , , and candidate genes (for ) were analysed by qRT-PCR and showed that gene expression changed at the analysed time points. Identification of molecular markers coupled to the genes studied was also carried out to confirm the presence of these genes in wheat hybrids. qRT-PCR was used to examine the expression levels of the resistance genes. The highest expression of genes ( , , , and ) occurred at 12 and 24 hpi, and such expression profiles were obtained for only one candidate gene among the four genes analysed ( ), indicating that it may be involved in resistance mechanisms of response to infection.