Ultrastructure observation and transcriptome analysis of Chinese chestnut (Castanea mollissima Blume) seeds in response to water loss

Abstract

Chestnut hardening is a physiological disorder that can occur after harvest. In this study, ultrastructure observation and transcriptome analysis were performed on samples collected at different time points during the chestnut hardening process. The SEM results showed that dehydration causes degradation of the cell wall and escape of starch granules from cells. Transcriptome analysis was performed, and a total of 40315 differential expressed genes were obtained and annotated into 50 GO terms and 20 major KEGG metabolic pathways. Weighted correlation network analysis of the DEGs revealed 12 co-expression modules, with 51–2965 DEGs in each module. Six co-expression modules significantly correlated with the chestnut hardening process. A total of 32 hub genes were screened by weight value and intramodular connectivity. The gene CMHBY209828 might play a key role in the chestnut hardening process. This research provides the theoretical basis to further understand the response of chestnuts to water loss.