Wang Shoule, Zhao Zhenyong, Ge Shaoqing, Peng Bin, Zhang Ke, Hu Mingfang, Mai Wenxuan, Tian Changyan
State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, China.
University of Chinese Academy of Sciences, Beijing, China.
Front Plant Sci. 2021 Jun 21;12:677767. doi: 10.3389/fpls.2021.677767. eCollection 2021.
Halophytes are capable of resisting salinity, and their root system is the part in direct contact with the saline soil environment. The aim of this study was to compare the responses of root morphology and rhizosphere characteristics to salinity between a halophyte, (suaeda), and a glycophyte, L. (sugar beet). The soil salt content was set to four levels (0.7, 1.2, 1.7, and 2.7%) by NaCl-treated plants. We investigated the soil pH, EC, nutrients and soil, plant ion (Na, Cl, K, and Mg) concentration to evaluate the rhizospheric processes, and salt tolerance of suaeda by the root mat method. The highest biomass was in the 1.2% salt level for suaeda and in the 0.7% salt level for sugar beet. The root length and root surface area of suaeda showed similar trends to biomass, but the root diameter decreased by 11.5-17.9% with higher salinity. The Na, Cl, and K accumulations in the shoot of suaeda displayed higher than that in sugar beet, while the Mg accumulation was lower in suaeda than that in sugar beet. High salinity resulted in increased pH and EC values in the rhizosphere for suaeda, but lower values of these parameters for sugar beet. Under high salinity, the Olsen phosphorus content was 0.50 g·kg and 0.99 g·kg higher in the rhizosphere than in the non-rhizosphere for suaeda and sugar beet. We concluded that the two species [halophyte, (suaeda), and a glycophyte, L. (sugar beet)] showed diverse approaches for nutrient absorption under salinity stress. Suaeda altered its root morphology (smaller root diameter and longer roots) under salt stress to increase the root surface area, while sugar beet activated rhizospheric processes to take up more nutrients.
盐生植物能够抵抗盐分，其根系是与盐渍土壤环境直接接触的部分。本研究的目的是比较盐生植物（碱蓬）和甜土植物（甜菜）的根系形态和根际特征对盐分的响应。通过用NaCl处理植株，将土壤盐分含量设置为四个水平（0.7%、1.2%、1.7%和2.7%）。我们采用根垫法研究了土壤pH值、电导率、养分以及土壤和植物离子（钠、氯、钾和镁）浓度，以评估根际过程和碱蓬的耐盐性。碱蓬在1.2%盐浓度水平下生物量最高，甜菜在0.7%盐浓度水平下生物量最高。碱蓬的根长和根表面积与生物量呈现相似趋势，但随着盐度升高，根直径下降了11.5 - 17.9%。碱蓬地上部的钠、氯和钾积累量高于甜菜，而碱蓬地上部的镁积累量低于甜菜。高盐度导致碱蓬根际的pH值和电导率升高，但甜菜根际的这些参数值较低。在高盐度条件下，碱蓬和甜菜根际的 Olsen 磷含量分别比非根际高0.50 g·kg和0.99 g·kg。我们得出结论，这两个物种[盐生植物（碱蓬）和甜土植物（甜菜）]在盐胁迫下表现出不同的养分吸收方式。碱蓬在盐胁迫下改变其根系形态（根直径变小、根变长）以增加根表面积，而甜菜则激活根际过程以吸收更多养分。
