Abstract:

The aim of this study was to screen out important regulatory genes in sugar beet in response to drought stress, and to provide reference for the selection and breeding of drought-resistant sugar beet varieties in China. The transcriptome of sugar beet ‘KWS2314’ seeds was sequenced at three stages of the germination process. Key gene modules were measured by WGCNA analysis. GO analysis of differentially expressed genes revealed changes in the molecular functions, cellular components and biological processes of the differential genes in response to drought stress in plants. The highest number of catalytically active genes for molecular functions, cellular genes for cellular composition and genes for metabolic processes for biological processes were found in the comparison of CK₀-vs-T₁, CK₀-vs-T₂, CK₁-vsT₁ and CK₁-vsT₂. In KEGG enrichment analyses, significant enrichment was found for pathways between CK₀, CK₁, CK₂ in the control group and T₁, T₂ in the treatment group. The two pathways with the highest frequencies were the metabolic pathway and the biosynthesis of secondary metabolites pathway, suggesting that the metabolism of glucose, fats, and proteins was closely linked to drought. This work elucidated the molecular mechanism of sugar beet seed germination under water deficit environment, and laid a theoretical basis for plant drought resistance research.

Key words: beets (Beta vulgaris L.), drought stress, germination period, transcriptome, plant metabolism, RNA extraction, KEGG enrichment analysis, GO enrichment analysis