Sugarcane is an important crop worldwide, and most sugar is derived directly from sugarcane. Due to its thermophilic nature, the yield of sugarcane is largely influenced by extreme climate conditions, especially cold stress. Therefore, the development of sugarcane with improved cold tolerance is an important goal. However, little is known about the multiple mechanisms underlying cold acclimation at the bud stage in sugarcane. In this study, we emphasized that sensitivity to cold stress was higher for the sugarcane variety ROC22 than for GT42, as determined by physical signs, including bud growth capacity, relative conductivity, malonaldehyde contents, and soluble sugar contents. To understand the factors contributing to the difference in cold tolerance between ROC22 and GT42, comparative transcriptome analyses were performed. We found that genes involved in the regulation of the stability of the membrane system were the relative determinants of difference in cold tolerance. Additionally, genes related to protein kinase activity, starch metabolism, and calcium signal transduction were associated with cold tolerance. Finally, 25 candidate genes, including 23 variety-specific and 2 common genes, and 7 transcription factors were screened out for understanding the possible cold resistance mechanism. The findings of this study provide candidate gene resources for cold resistance and will improve our understanding of the regulation of cold tolerance at the bud stage in sugarcane.

甘蔗是世界范围内的重要作物，大部分糖分直接来自甘蔗。由于其嗜热性质，甘蔗的产量在很大程度上受极端气候条件的影响，尤其是冷胁迫。因此，开发耐寒性更强的甘蔗是一个重要的目标。然而，人们对甘蔗芽期冷驯化的多种机制知之甚少。在这项研究中，我们强调甘蔗品种 ROC22 对冷胁迫的敏感性高于 GT42，这是由生理特征决定的，包括芽生长能力、相对电导率、丙二醛含量和可溶性糖含量。为了了解导致 ROC22 和 GT42 之间耐冷性差异的因素，进行了比较转录组分析。我们发现参与调节膜系统稳定性的基因是耐寒性差异的相对决定因素。此外，与蛋白激酶活性、淀粉代谢和钙信号转导相关的基因与耐寒性有关。最终筛选出25个候选基因，包括23个品种特异性基因和2个常见基因，以及7个转录因子，以了解可能的抗寒机制。本研究结果为抗寒基因提供了候选基因资源，将增进我们对甘蔗芽期耐寒调控的认识。淀粉代谢和钙信号转导与耐寒性有关。最终筛选出25个候选基因，包括23个品种特异性基因和2个常见基因，以及7个转录因子，以了解可能的抗寒机制。本研究结果为抗寒基因提供了候选基因资源，将增进我们对甘蔗芽期耐寒调控的认识。淀粉代谢和钙信号转导与耐寒性有关。最终筛选出25个候选基因，包括23个品种特异性基因和2个常见基因，以及7个转录因子，以了解可能的抗寒机制。本研究结果为抗寒基因提供了候选基因资源，将增进我们对甘蔗芽期耐寒调控的认识。