Abstract:
To identify the key indicators for salt tolerance evaluation of Salix matsudana Koidz, we explored the relationship of ion absorption and distribution with chlorophyll, fluorescence parameters (leaf performance index, maximum photochemical efficiency), and photosynthetic gas parameters (net photosynthetic rate, transpiration, stomatal conductance, intercellular carbon dioxide concentration) under salt stress. We established 4 treatment groups and one control group based on salinity levels of NaCl hydroponic solutions (171, 342, 513, and 684 mm). The Na+/K+, Na+/Ca2+, chlorophyll fluorescence, and photosynthetic parameters of leaves were measured on the 1st, 3rd, 5th, 8th, 11th, and 15th days to analyze the correlations of chlorophyll, chlorophyll fluorescence and photosynthetic parameters to the ion distribution ratio. The results showed that (1) The ratio of the dry weight of roots to leaves gradually increased with increasing salt concentration, whereas the water content of leaves and roots first increased and then decreased with increasing time. (2) The content of Na+, Na+/K+, and Na+/Ca2+ in roots and leaves increased with increasing salt stress concentration and treatment time, and the difference gradually narrowed. (3) Ca2+ was lost more than K+ under salt stress, and Na+/Ca2+ was more sensitive to the salt stress environment than Na+/K+. (4) Because the root system had a retention effect, both Na+/K+ and Na+/Ca2+ in roots under different NaCl concentrations and different treatment times were higher than those in leaves, and Na+/Ca2+ was much higher than Na+/K+ in roots. (5) Na+/K+ had a higher correlation with fluorescence parameters than Na+/Ca2+. Among them, Na+/K+ had a significantly negative correlation with the maximum photochemical efficiency, and the correlation coefficient R 2 was 0.8576. (6) Photosynthetic gas parameters had a higher correlation with Na+/Ca2+ than with Na+/K+. Among them, significantly negative correlations were noted between Na+/Ca2+ and Gs as well as between Na+/Ca2+ and E under salt stress. The correlation between Na+/Ca2+ and Gs was the highest with a correlation coefficient of 0.9368. (7) Na+/K+ and Na+/Ca2+ had no significant correlation with chlorophylls. Na+/Ca2+ was selected as a key index to evaluate the salt tolerance of S. matsudana Koidz, and the results provided a reference for analyzing the relationship between ion transport and distribution for photosynthesis.
摘要:
确定柳柳耐盐性评价的关键指标,我们探索了离子吸收和分配与叶绿素的关系,荧光参数(叶片性能指标,最大光化学效率),和光合气体参数(净光合速率,蒸腾作用,气孔导度,细胞间二氧化碳浓度)在盐胁迫下。我们根据NaCl水培溶液的盐度水平(171、342、513和684mm)建立了4个处理组和一个对照组。Na+/K+,Na+/Ca2+,叶绿素荧光,1日测定了叶片的光合参数,3rd,5th,8th,第十一,第15天分析叶绿素的相关性,叶绿素荧光和光合参数对离子的分配比。结果表明:(1)根与叶的干重比随着盐浓度的增加而逐渐增加,随着时间的增加,叶片和根的含水量先增加后减少。(2)Na+的含量,Na+/K+,根和叶片中的Na+/Ca2+随盐胁迫浓度和处理时间的增加而增加,差异逐渐缩小。(3)在盐胁迫下,Ca2+比K+损失更多,Na+/Ca2+对盐胁迫环境的敏感性高于Na+/K+。(4)由于根系具有保留作用,不同NaCl浓度和不同处理时间下根系Na+/K+和Na+/Ca2+均高于叶片,根中Na+/Ca2+远高于Na+/K+。(5)Na+/K+与荧光参数的相关性高于Na+/Ca2+。其中,Na+/K+与最大光化学效率呈显著负相关,相关系数R2为0.8576。(6)光合气体参数与Na+/Ca2+的相关性高于与Na+/K+的相关性。其中,在盐胁迫下,Na/Ca2与Gs之间以及Na/Ca2与E之间存在显着负相关。Na+/Ca2+与Gs的相关性最高,相关系数为0.9368。(7)Na+/K+和Na+/Ca2+与叶绿素无显著相干性。选择Na+/Ca2+作为评价马苏达纳·科伊兹的耐盐性的关键指标,研究结果为分析光合作用中离子迁移与分布的关系提供了参考。