Objective The study was carried out to identify genes related to low-temperature germination ability in sweet corn through transcriptome sequencing of inbred lines with different germination ability at low-temperature.

Method Using the sweet corn inbred line Scil-H7th with strong low-temperature germination ability as a donor, NILs (near-isogenic lines) were constructed and NILs with different low-temperature germination ability were obtained, then genes related to low-temperature germination were selected through physiological determination, transcriptomic analysis and qRT-PCR.

Result The differentially expressed genes (DEGs) within lines in different germination stages and DEGs among lines in the same germination stages were comparatively analyzed. Among different materials at the same germination stage, a total of 410 DEGs in all the four comparisons were obtained, among which 65 genes were only expressed in the high seed vigor material Scil-H7th and the near-isogenic line L18 but not expressed in the low seed vigor rotation parent (Scil-C4th). 32 of these genes were functionally annotated. Combined with bioinformatics analysis and expression analysis, 20 DEGs were identified to be highly associated with low-temperature germination. From the 20 candidates, expression profile of 7 genes with upper-regulated transcriptome sequencing were analyzed with qRT-PCR; among them, the Zm00001d037383, encoding UDP-glucosyltransferase, was highly expressed in embryos of DP and hypothesized to play a key role in low-temperature tolerant germination in sweet corn.

Conclusion The transcriptome sequencing analysis identified genes related to low-temperature germination ability in sweet corn, which laid a foundation for the development of sweet corn with better germination ability at low temperature.