Author:
Wang Hongli,Cheng Xi,Shi Qiyu,Xu Jie,Chen Dongliang,Luo Chang,Liu Hua,Cao Li,Huang Conglin
Abstract
Members of theRosagenus have a high ornamental value, but their cultivation area is limited by their sensitivity to cold temperatures. The aim of this study was to evaluate the cold tolerance of a range ofRosamaterials, and then determine which genes were related to cold tolerance. NineRosamaterials were subjected to a cold treatment. To identify genes related to cold tolerance,R. hybridawas treated at −15°C for 10 min, and leaves collected before and after this treatment were collected for RNA-Seq analyses. The transcript profiles of four DEGs (POD17, NDUFA9, PMA1, andb-Amy1) inR. hybridawere determined by qRT-PCR at 0 h, 1 h, 2 h, and 3 h at −15°C. NineRosamaterials were subjected to a cold treatment, and the most cold-tolerant materials were identified as those that showed the lowest levels of electrolyte leakage and the best recovery after 30 d of growth. The most cold-tolerant materials wereRosa hybrida, Rosa rugosa‘Pingyin 12’, andRosa rugosa. In total, 204 significantly differentially expressed genes (DEGs) were identified, of which 88 were significantly up-regulated and 116 were significantly down-regulated under cold conditions. Gene Ontology classification and Kyoto Encyclopedia of Genes and Genomes pathway analyses showed that the DEGs were enriched in 57 pathways, especially starch and sucrose metabolism, phenylpropane biosynthesis, MAPK signaling, fructose and mannose metabolism, and oxidative phosphorylation. By transcriptional analysis,PMA1, which was related to H+ATPase activity, was continuously up-regulated, but the transcript levels ofPOD17, NDUFA9, andβ-Amy1fluctuated during the freezing treatment. This research uncovered scarce cold-resistant materials and layed the foundation for further research on the cold tolerance mechanism ofRosaplants and the breeding of cold-tolerant varieties.