Center of Excellence in Environment and Plant Physiology, Department of Botany, Faculty of Science, Chulalongkorn University, Bangkok, 10330, Thailand.
Division of Biology, School of Science, University of Phayao, Phayao, 56000, Thailand.
Protoplasma. 2021 Sep;258(5):1119-1131. doi: 10.1007/s00709-021-01629-x. Epub 2021 Mar 6.
How to capture the rice varieties salt stress sensitivity? Here, we measure responses of root border cells (1 day, ± 60 mM NaCl) and apply multi-logistic quantification of growth variables (21 days, ± 60 mM NaCl) to two rice varieties, salt-sensitive IR29 and tolerant Pokkali. Thus, logistic models determine the maximum response velocities (Vmax) and times of half-maximum (T0) for root border cell (RBC) and growth parameters. Thereof, seven variables show logistic models (0.58 < R ≤ 1) and monotonous responses in both Pokkali and IR29: root to shoot ratio by water content, primary root length, shoot water, adventitious root number, shoot dry and fresh weight, and root dry weight. Moreover, the regression to lognormal distribution (R = 0.99) of these seven Vmax fractionated by T0 represents the rice variety's comprehensive response. Its quotient IR29/Pokkali is peaking at 98-fold higher velocity of IR29, thus capturing the variety's sensitivity. Consequently, our finding of 66-fold higher Vmax of primary root length response of IR29 indicates an essential salt sensor in the root, including RBC. Finally, the effects of salt stress on RBC confirm multi-logistic quantification, showing 36% decrease of RBC mucilage layer in IR29, without change in Pokkali. Inversely, RBC number of Pokkali increases 43% without change in IR29. Briefly, this suggests both RBC and multi-logistic quantification for the screening for salt tolerance in two thousand rice varieties.
如何捕捉水稻品种的耐盐敏感性？在这里，我们测量了根边缘细胞（1 天，±60mMNaCl）的响应，并应用多对数量化生长变量（21 天，±60mMNaCl）来研究两个水稻品种，盐敏感 IR29 和耐盐性 Pokkali。因此，逻辑模型确定了根边缘细胞（RBC）和生长参数的最大响应速度（Vmax）和半最大值时间（T0）。其中，有七个变量显示出逻辑模型（0.58<R≤1），并且在 Pokkali 和 IR29 中都有单调的响应：根到茎的水分比、主根长度、茎水、不定根数量、茎干重和鲜重以及根干重。此外，这些七个 Vmax 按 T0 进行对数正态分布（R=0.99）的回归表示了水稻品种的综合响应。其 IR29/Pokkali 的商在 IR29 中达到 98 倍的速度峰值，从而捕捉到了品种的敏感性。因此，我们发现 IR29 的主根长度响应的 Vmax 高出 66 倍，这表明根中存在一种重要的盐传感器，包括 RBC。最后，盐胁迫对 RBC 的影响证实了多对数量化，表明 IR29 中 RBC 粘液层减少了 36%，而 Pokkali 则没有变化。相反，Pokkali 的 RBC 数量增加了 43%，而 IR29 则没有变化。简而言之，这表明 RBC 和多对数量化可用于筛选两千个水稻品种的耐盐性。
