Abstract

In this study, the cold-tolerance capacity of 133 varieties of weedy rice was evaluated based on the comprehensive evaluation index D, with Kongyu 131 used as a cold-tolerant control. A total of 39.8% of the 133 varieties were considered ‘strong’, indicating that weedy rice populations indeed have relatively strong cold-tolerance capacity as a whole, and the robust cold-tolerant varieties WR29 and WR157 were identified. Regression analysis showed that the metrics including the nitrogen recovery index, superoxide dismutase (SOD) content and malondialdehyde (MDA) content correlated significantly (P < 0.05) with cold tolerance and could be used as indicators of cold tolerance. On the basis of a transcriptome analysis of WR157, a robust cold-tolerant variety identified in this study, a total of 4645 putative DEGs were identified in treated groups compared to the control groups, with 2123 upregulated DEGs and 2522 downregulated DEGs. All upregulated DEGs were enriched on 1388 terms, all downregulated DEGs were enriched on 1566 terms; 911 of the 2123 upregulated DEGs fell into 98 KEGG categories and 1103 of the 2522 downregulated DEGs were in 115 categories. Further analysis showed that GO:0019740 and GO:0006808 are involved in nitrogen utilization; GO:0009269 and GO:0009414 are related to the stress response; and GO:0016491 and GO:0016614 are related to oxidoreductase activity.

Background

Weedy rice (Oryza) is a related pest species of cultivated rice (Oryza sativa L.) that has strong abiotic stress resistance; however, the comprehensive mechanism governing its cold tolerance is poorly understood.

Conclusion

Our comprehensive evaluation based on five morphological indices and nine physiological indicators revealed outstanding levels of cold-tolerance capacity among weedy rice varieties from different regions and revealed some terms related to cold tolerance via transcriptome analysis. Our results underscored the reliable evaluation methods for additional cold tolerance studies and revealed several genes related to cold tolerance, which will help researchers breed cultivated rice varieties to increase their cold-tolerance capacity. These traits have the ability to increase seedling survival rate and growth, as well as future yields.

中文翻译：

---

基于杂草水稻幼苗转录组的耐寒性机理综合评价与分析

摘要

本研究以综合评价指数D为基础，对133个杂草稻品种的耐寒性进行了评价，以空育131为耐寒性对照。133个品种中有39.8％被认为是“强”，表明杂草稻种群总体上确实具有相对较强的耐寒能力，并且鉴定出了健壮的耐寒品种WR29和WR157。回归分析显示，氮回收指数，超氧化物歧化酶（SOD）含量和丙二醛（MDA）含量等指标之间具有显着相关性（P <0.05）并具有耐寒性，可以用作耐寒性的指标。根据WR157的转录组分析，该研究确定了一个强大的耐寒品种，与对照组相比，治疗组总共鉴定出4645个DEG，其中DEG上调2123个，DEG下调2522个。所有上调的DEG均富集了1388个词，所有下调的DEG均富集了1566个词；2123个上调的DEG中有911个属于KEGG类别，而2522个下调的DEG中有1103个属于115个类别。进一步的分析表明，GO：0019740和GO：0006808参与了氮的利用。GO：0009269和GO：0009414与应力响应有关；GO：0016491和GO：0016614与氧化还原酶活性有关。

背景

杂草稻（Oryza）是一种栽培稻（Oryza sativa L.）的相关有害生物，具有很强的非生物逆境抗性。然而，对其耐寒性的综合机制了解甚少。

结论

我们基于五个形态指标和九个生理指标的综合评估显示，不同地区的杂草水稻品种具有优异的耐寒性水平，并通过转录组分析揭示了一些与耐寒性相关的术语。我们的结果强调了用于其他耐寒性研究的可靠评估方法，并揭示了几个与耐寒性有关的基因，这将有助于研究人员培育栽培水稻品种以提高其耐寒性。这些性状具有提高幼苗成活率和生长以及未来产量的能力。