通过转录组比较分析挖掘木薯块根耐储关键基因

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中图分类号：S533 文献标志码：A

Abstract：【Objective】Root tuber storage tolerance is an important economic trait in cassava， which is controlled by genetics，but the related genes are not yet known. Therefore，this study aimed to explore the genes related with cassava postharvest physiological degradation（PPD）through tran‐ scriptome sequencing to provide a reference for breeding cassava varieties with root storage toler‐ ance.【Method】Transcriptome sequencing was performed for the PPD tolerant cassava variety South China 14（SC14）and the control variety Guire 15231（GR15231）that is prone to PPD. Raw sequencing data were subjected to quality assessment，identification and statistical analysis of differ‐ entially expressed genes（DEGs），functional annotation，expression heatmap visualization，and min‐ ing of key regulatory genes and functional genes involved in PPD progression.【Result】In this study，high -quality transcriptome sequencing data were obtained，the sample clustering effect was significant and the intra-group repeatability was good. High-quality sequencing data were obtained for in-depth analysis. A total of 14 791 DEGs were identified through differential expression analy‐ sis. Comparative GO and KEGG enrichment analysis of the DEGs between day 0 and day 12 after harvest revealed that the upregulated genes in GR15231 and SC14 were significantly enriched in sec‐ ondary metabolism，antioxidant redox processes，and phenylpropanoid biosynthesis，while the down‐ regulated genes were associated with carbohydrate synthesis and metabolism. Notably，SC14 specific upregulated genes were enriched in pathogen response and defense pathways，distinguishing those from GR15231. Finally，36 candidate genes linked to PPD tolerance were identified，participating in lignin synthesis，redox regulation，disease resistance，and starch/sucrose metabolism，which play crit‐ ical roles in cassava’s stress adaptation.【Conclusion】Compared with the cassava variety GR15231 prone to PPD，a large number of genes in roots of the PPD tolerant cassava variety SC14 were signif‐ icantly upregulated in the metabolic pathways such as antioxidant reduction，response and defense against pathogenic bacteria. This study identified 36 storability related genes，providing gene re‐ sources for the breeding of new cassava varieties resistant to PPD.

Keywords：Cassava；transcriptome；postharvest physiological deterioration；storage tolerant gene

0 引言

【研究意义】 木薯（Manihot esculenta Crantz）作为重要淀粉作物，广泛分布在热带及亚热带地区，其繁殖方式主要为茎秆埋杆或扦插。（剩余23949字）