Genome-Wide Identification and Expression Analysis of Rosa roxburghii Autophagy-Related Genes in Response to Top-Rot Disease

Autophagy is a highly conserved process in eukaryotes that degrades and recycles damaged cells in plants and is involved in plant growth, development, senescence, and resistance to external stress. Top-rot disease (TRD) in Rosa roxburghii fruits caused by Colletotrichum fructicola often leads to huge yield losses. However, little information is available about the autophagy underlying the defense response to TRD. Here, we identified a total of 40 R. roxburghii autophagy-related genes (RrATGs), which were highly homologous to Arabidopsis thaliana ATGs. Transcriptomic data show that RrATGs were involved in the development and ripening processes of R. roxburghii fruits. Gene expression patterns in fruits with different degrees of TRD occurrence suggest that several members of the RrATGs family responded to TRD, of which RrATG18e was significantly up-regulated at the initial infection stage of C. fructicola. Furthermore, exogenous calcium (Ca2+) significantly promoted the mRNA accumulation of RrATG18e and fruit resistance to TRD, suggesting that this gene might be involved in the calcium-mediated TRD defense response. This study provided a better understanding of R. roxburghii autophagy-related genes and their potential roles in disease resistance.

Automated summary

Autophagy is a highly conserved process in eukaryotes that is involved in the degradation and recycling of damaged cells in plants, and plays a role in plant growth, development, senescence, and resistance to external stress. In this study, researchers identified 40 autophagy-related genes (RrATGs) in Rosa roxburghii fruits, and found that RrATG18e gene was significantly up-regulated during the initial infection stage of Colletotrichum fructicola, the pathogen causing Top-rot disease (TRD). Additionally, exogenous calcium (Ca2+) was found to enhance the expression of RrATG18e and increase fruit resistance to TRD, indicating its involvement in calcium-mediated defense response. This study provides insights into the role of R. roxburghii autophagy-related genes in disease resistance.