Wheat transcriptome changes in response to the black stem rust pathogen (Puccinia graminis f. sp. tritici)

Wheat is a crucial staple crop worldwide, playing an essential role in global food security. Among cereal rust pathogens, Puccinia graminis f. sp. tritici (Pgt) is particularly devastating to wheat cultivation, often causing severe yield losses. The rapid evolution of Pgt populations limits the genetic resistance of wheat and complicates disease management strategies. Understanding the molecular mechanisms underlying infection and susceptibility can provide new approaches for enhancing crop resistance through genetic manipulation of disease susceptibility. In this context, transcriptome analysis of wheat plants in response to rust infection, under both compatible and incompatible interactions, can help identify key genes and biochemical pathways involved in disease resistance or susceptibility. This study aimed to investigate changes in gene expression and identify key genes of wheat involved in the interaction with wheat stem rust by analyzing genetic responses in a rust-susceptible wheat variety. The results revealed that genes involved in signaling pathways, pathogen resistance, and stress responses were significantly down-regulated, while genes associated with photosynthetic pathways, oxidoreductase activity, and energy production were highly up-regulated. Expression analysis using qRT-PCR showed that among the genes responsible for the production of antioxidant enzymes (CAT, SOD, and GPX) in infected plants, SOD was down-regulated, GPX was up-regulated, and no change in the expression of the CAT gene was observed. The authors suggested that the observed discrepancy between transcriptional and protein levels highlights the complexity of the reactive oxygen species (ROS) metabolic pathway.