Abstract
High sucrose content is a crucial breeding objective in sugarcane, with significant differences in sucrose accumulation patterns between early and late-maturing varieties during different growth stages. This study aimed to determine how differences in cane maturation affect proteins involved in sucrose metabolism. The isobaric tags for relative and absolute quantitation (iTRAQ) technique was employed to analyze intraspecific and interspecific proteomic differences between the early-maturing sugarcane variety ‘GL05-136’ and the late-maturing variety ‘GR2’ during the maturation period (January and February). A total of 3337 proteins were identified. Gene Ontology, Kyoto Encyclopedia of Genes and Genomes (KEGG), and Clusters of Orthologous Genes analysis found that the differential proteins were mainly associated with metabolic processes, single biological processes, and cellular processes. A total of 47 differential proteins were identified in the four comparison groups (intra-variety temporal comparisons and inter-variety synchronous comparisons), 17 of which were enriched in a KEGG pathway, including glucose metabolism, stress resistance, and photosynthesis pathways. The differential proteins fructose-bisphosphate aldolase and disulfide isomerase were obtained after further screening of the contrast groups between varieties. These two proteins may be associated with differential cane maturation, sucrose synthesis and accumulation in sugarcane. These results provide more insights on sucrose accumulation and stalk maturation in sugarcane varieties.