我们进行了一项研究,以检查从中国海南岛采集的12种不同生态型的无茎无茎的生长和生理变化。这些生态型受到不同浓度(0、200、400和600mmol/L)氯化钠(NaCl)盐胁迫14天。我们还分析了与应激反应相关的代谢基因的表达。在低盐胁迫下,K地区的株高等指标(0mmol/L:45%,最高为200mmol/L:80%),节间长度(0mmol/L:0.38,200mmol/L:0.87,400mmol/L:0.25和600mmol/L:1.35),以及叶面积,相对含水量,鲜重,和干重随盐浓度的增加呈总体增加趋势。然而,随着盐浓度的增加,这些指标呈下降趋势。脯氨酸和丙二醛含量随盐浓度的增加而增加。当NaCl浓度为400mmol/L时,E地区叶片中MDA含量最高(196.23%),F(94.28%),J(170.10%),与对照组相比,K(136.08%),分别。大多数材料显示叶绿素a显着下降,叶绿素b,和总叶绿素含量与对照组相比。此外,叶绿素a与叶绿素b(Rab)的比例在不同材料之间有所不同。使用主成分分析,我们确定了三种生态型(L来自兴隆村,Dan州市;水沟坡村的B,陵水县;和海洞坊公园的J,东方市)代表高,中等,和低耐盐性水平,分别,基于上述生长和生理指标。为了进一步研究相关基因在转录水平上的表达变化,我们采用qRT-PCR。结果表明,随着盐浓度的升高,SpP5CS1、SpLOX1和SpLOX1基因的相对表达量增加,这对应于脯氨酸和丙二醛含量的积累,分别。然而,SpCHL1a和SpCHL1b的相对表达模式不一致.这项研究有助于我们了解真正的盐生植物S.hypulacastrum的耐盐机制,为该领域的进一步研究提供了坚实的理论基础。
We conducted a study to examine the growth and physiological changes in 12 different ecotypes of Sesuvium portulacastrum collected from Hainan Island in
China. These ecotypes were subjected to different concentrations (0, 200, 400, and 600 mmol/L) of sodium chloride (NaCl) salt stress for 14 days. We also analyzed the expression of metabolic genes related to stress response. Under low salt stress, indicators such as plant height in region K (0 mmol/L: 45% and highest at 200 mmol/L: 80%), internode length (0 mmol/L: 0.38, 200 mmol/L: 0.87, 400 mmol/L: 0.25, and 600 mmol/L: 1.35), as well as leaf area, relative water content, fresh weight, and dry weight exhibited an overall increasing trend with the increase in salt concentration. However, as the salt concentration increased, these indicators showed a decreasing trend. Proline and malondialdehyde contents increased with higher salt concentrations. When the NaCl concentration was 400 mmol/L, MDA content in the leaves was highest in the regions E (196.23%), F (94.28%), J (170.10%), and K (136.08%) as compared to the control group, respectively. Most materials demonstrated a significant decrease in chlorophyll a, chlorophyll b, and total chlorophyll content compared to the control group. Furthermore, the ratio of chlorophyll a to chlorophyll b (Rab) varied among different materials. Using principal component analysis, we identified three ecotypes (L from Xinglong Village, Danzhou City; B from Shuigoupo Village, Lingshui County; and J from Haidongfang Park, Dongfang City) that represented high, medium, and low salt tolerance levels, respectively, based on the above growth and physiological indexes. To further investigate the expression changes of related genes at the transcriptional level, we employed qRT-PCR. The results showed that the relative expression of SpP5CS1, SpLOX1, and SpLOX1 genes increased with higher salt concentrations, which corresponded to the accumulation of proline and malondialdehyde content, respectively. However, the relative expression of SpCHL1a and SpCHL1b did not exhibit a consistent pattern. This study contributes to our understanding of the salt tolerance mechanism in the true halophyte S. portulacastrum, providing a solid theoretical foundation for further research in this field.