Zhang Xijuan, Liu Kai, Yang Chuanming, Hou Benfu, Yang Xianli, Wang Lizhi, Cui Shize, Lai Yongcai, Li Zhugang, Jiang Shukun
Crop Cultivation and Tillage Institute of Heilongjiang Academy of Agricultural Sciences, Harbin 150086, China.
Northeast Branch of National Salt-Alkali Tolerant Rice Technology Innovation Center, Harbin 150086, China.
Life (Basel). 2024 Sep 11;14(9):1151. doi: 10.3390/life14091151.
Salt-alkaline stress is one of the most stressful occurrences, causing negative effects on plant development and agricultural yield. Identifying and utilizing genes that affect alkaline tolerance is an excellent approach to accelerate breeding processes and meet the needs for remediating saline-alkaline soil. Here, we employed a mapping population of 176 recombinant inbred lines (RILs) produced from a cross between alkali-tolerant Longdao5 and alkali-sensitive Zhongyouzao8 to identify the quantitative trait loci (QTLs) determining alkali tolerance at the seedling stage. For the evaluation of alkali tolerance, the recovered seedling's average alkali tolerance index (ATI), root number (RN), root length (RL), seedling dry weight (SW), root dry weight (RW), and seedling height (SH) were assessed, together with their relative alkaline damage rate. Under alkaline stress, the ATI was substantially negative connected with the root number, seedling height, seedling dry weight, and root dry weight; however, it was considerably positive correlated with the relative alkaline damage rate of the root number and root dry weight. A total of 13 QTLs for the root number, root length, seedling height, seedling dry weight, root dry weight, and alkali tolerance index under alkaline stress were identified, which were distributed across chromosomes 1, 2, 3, 4, 5, 7, and 8. All of these QTLs formed two QTL clusters for alkali tolerance on chromosome 5 and chromosome 7, designated and , respectively. Nine QTLs were identified for the relative alkaline damage rate of the root number, root length, seedling height, seedling dry weight, and root dry weight under alkali stress. These QTLs were located on chromosome 2, 4, 6, 7, 8, 9, and 12. In conclusion, these findings further strengthen our knowledge about rice's genetic mechanisms for alkaline tolerance. This research offers clues to accelerate breeding programs for new alkaline-tolerance rice varieties.
盐碱胁迫是最具胁迫性的情况之一，对植物生长发育和农业产量产生负面影响。鉴定和利用影响耐碱性的基因是加速育种进程以及满足盐碱地改良需求的绝佳方法。在此，我们利用由耐碱品种龙稻5和碱敏感品种中优早8杂交产生的176个重组自交系（RIL）构建的定位群体，来鉴定决定苗期耐碱性的数量性状位点（QTL）。为了评估耐碱性，测定了复水后幼苗的平均耐碱指数（ATI）、根数（RN）、根长（RL）、地上部干重（SW）、根干重（RW）、苗高（SH），以及它们的相对碱害率。在碱性胁迫下，ATI与根数、苗高、地上部干重和根干重呈显著负相关；然而，它与根数和根干重的相对碱害率呈显著正相关。共鉴定出13个与碱性胁迫下根数、根长、苗高、地上部干重、根干重和耐碱指数相关的QTL，它们分布在第1、2、3、4、5、7和8号染色体上。所有这些QTL在第5号和第7号染色体上形成了两个耐碱QTL簇，分别命名为 和 。鉴定出9个与碱性胁迫下根数、根长、苗高、地上部干重和根干重的相对碱害率相关的QTL。这些QTL位于第2、4、6、7、8、9和12号染色体上。总之，这些发现进一步加深了我们对水稻耐碱遗传机制的认识。本研究为加速耐碱水稻新品种的育种计划提供了线索。
