In-depth understanding of the genetic control of stripe rust resistance (Puccinia striiformis f. sp. tritici) induced in wheat (Triticum aestivum L.) by Trichoderma asperellum T34.

Abstract

Wheat stripe rust (Pst) causes severe yield losses worldwide. Due to the continuous appearance of new stripe rust races, resistance has been broken in most of the highly resistant genotypes in Egypt and worldwide. Therefore, looking for new ways to resist such a severe disease is urgently needed. Trichoderma asperellum strain T34 has been known as an effective bioagent against many crop diseases. It exists naturally in Egyptian fields. Therefore, in the recent study, the effectiveness of T34 was tested as a bioagent against wheat stripe rust. For this purpose, 198-spring wheat genotypes were tested for their resistance against two different Pst populations collected from the Egyptian fields. The highest aggressive Pst population was used to test the effectiveness of T34. Highly significant differences were found between T34 and stripe rust suggesting the effectiveness of T34 in stripe rust resistance. Genome-wide association study (GWAS) identified 48 gene models controlling the resistance under normal conditions and 46 gene models controlling T34-induced resistance. Out of these gene models, only one common gene model was found suggesting the presence of two different genetic systems controlling the resistance under each condition. The pathways of the biological processes were investigated under both conditions. This study provided depth understanding of genetic control, hence will accelerate the future of wheat breeding programs for stripe rust resistance.