Integration of transcriptomics, metabolomics, and hormone analysis revealed the formation of lesion spots inhibited by GA and CTK was related to cell death and disease resistance in bread wheat (Triticum aestivum L.)

https://bmcplantbiol.biomedcentral.com/articles/10.1186/s12870-024-05212-3

BMC Plant Biology,volume24, Article number:558(2024)

Cong Li,Lei Yan,Qian Liu,Rong Tian,Surong Wang,Muhammad Faisal Umer,Muhammad Junaid Jalil,Md Nahibuzzaman Lohani,Yanlin Liu,Huaping Tang,Qiang Xu,Qiantao Jiang,Guoyue Chen,Pengfei Qi,Yunfeng Jiang,Lulu Gou,Qifu Yao,Youliang Zheng,Yuming Wei&Jian Ma

Abstart

Background

Wheat is one of the important grain crops in the world. The formation of lesion spots related to cell death is involved in disease resistance, whereas the regulatory pathway of lesion spot production and resistance mechanism to pathogens in wheat is largely unknown.

Results

In this study, a pair of NILs (NIL-Lm5Wand NIL-Lm5M) was constructed from the BC1F4population by the wheat lesion mimic mutant MC21 and its wild genotype Chuannong 16. The formation of lesion spots in NIL-Lm5Msignificantly increased its resistance to stripe rust, and NIL-Lm5Mshowed superiour agronomic traits than NIL-Lm5Wunder stripe rust infection.Whereafter, the NILs were subjected to transcriptomic (stage N: no spots; stage S, only a few spots; and stage M, numerous spots), metabolomic (stage N and S), and hormone analysis (stage S), with samples taken from normal plants in the field. Transcriptomic analysis showed that the differentially expressed genes were enriched in plant-pathogen interaction, and defense-related genes were significantly upregulated following the formation of lesion spots. Metabolomic analysis showed that the differentially accumulated metabolites were enriched in energy metabolism, including amino acid metabolism, carbohydrate metabolism, and lipid metabolism. Correlation network diagrams of transcriptomic and metabolomic showed that they were both enriched in energy metabolism. Additionally, the contents of gibberellin A7, cis-Zeatin, and abscisic acid were decreased in leaves upon lesion spot formation, whereas the lesion spots in NIL-Lm5Mleaves were restrained by spaying GA and cytokinin (CTK, trans-zeatin) in the field.

Conclusion

The formation of lesion spots can result in cell death and enhance strip rust resistance by protein degradation pathway and defense-related genes overexpression in wheat. Besides, the formation of lesion spots was significantly affected by GA and CTK. Altogether, these results may contribute to the understanding of lesion spot formation in wheat and laid a foundation for regulating the resistance mechanism to stripe rust.