The responses of Urochloa brizantha and Megathyrsus maximus young seedlings to salt stress with NaCl at 0 (control), 25, 50 and 100 mmol/L under hydroponic conditions were studied. The relative growth rate of U. brizantha leaves was reduced at 50 and 100 mmol/L NaCl, whereas that of M. maximus leaves was not affected. Moreover, high oxidative damages, low chlorophyll content and severe reduction of osmotic potential were observed in U. brizantha leaves when subjected to 100 mmol/L NaCl. This grass also showed high accumulation of proline and soluble sugars in leaves and roots. M. maximus efficiently regulated leaf K⁺ concentration and restricted Na⁺ transport by retention in roots. The leaf K⁺/Na⁺ ratio was higher in M. maximus than in U. brizantha at 50 and 100 mmol/L NaCl. Overall, both grasses displayed different mechanisms to reduce the deleterious effects of salinity, but the control of ion homeostasis exhibited by M. maximus contributed notably to improved performance of this grass when grown under saline conditions.

中文翻译：

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两种盐处理过的牧草中的渗透液在叶片中的积累和根系对钠离子的排斥

研究了水培条件下0（对照），25、50和100 mmol / L NaCl对Urochloa brizantha和Megathyrsus maximus幼苗对盐胁迫的响应。在50和100 mmol / L NaCl浓度下，U。brizantha叶片的相对生长速率降低，而对M. maximus叶片的相对生长速率没有影响。此外，在100 mmol / L NaCl胁迫下，在茄子的叶片中观察到高的氧化损伤，低的叶绿素含量和严重的渗透势降低。这种草还显示出在叶和根中脯氨酸和可溶性糖的高积累。M. maximus有效调节叶片K ⁺浓度并限制Na⁺通过保留根来运输。叶ķ ⁺ /钠⁺比在更高M.鲆比U. brizantha在50和100毫摩尔/ L NaCl中。总体而言，两种草显示出不同的机制来减少盐分的有害影响，但是在盐分条件下生长时，最大分枝杆菌表现出的离子稳态控制显着改善了该草的性能。