55份不同生态型假俭草的耐盐性评价

Evaluation of salinity tolerance of 55 centipedegrass ecotypes

本研究采用水培的方法,在200mmol·L^(-1) NaCl胁迫下对55份假俭草(Eremochloa ophiuroides)生态型进行耐盐性评价。盐处理18d后对目测质量(TQ)、枯叶率(WLR)、相对生长量(ΔW)、叶绿素(Chl)含量和相对含水量(RWC)进行测定。结果表明,55份假俭草生态型间耐盐能力存在显著差异;与对照相比,盐处理18d后55份假俭草生态型及‘翠绿1号’品种的TQ、ΔW、Chl含量及RWC都显著降低(P<0.05),WLR都显著上升(P<0.05);相关分析表明,WLR与RWC及TQ显著负相关,相关系数分别为-0.85及-0.73,而RWC与TQ显著正相关,相关系数为0.70。通过主成分分析,提取到3个主成分,可以解释总变异的91.79%。隶属函数法耐盐能力排序及聚类分析表明,CP52、CP15、CP51及CP49的耐盐性最强,这些假俭草生态型有望在滨海盐碱土的草坪绿化中应用。

In this study, the salt tolerance of 55 centipedegrass （Eremochloa ophiuroides） ecotypes was evaluated under 200 mmol·L-1 NaCl using a hydroponic system. Turf quality （TQ）, withered leaf rate （WLR）, relative growth （ΔW）, chlorophyll （Chl） content, and relative water content （RWC） were measured after 18 d of salt treatment. The results showed that there were significant salt tolerance differences among the 55 centipedegrass ecotypes. Compared with the control, the TQ, ΔW, Chl content, and RWC of all centipedegrass ecotypes and cv. ‘cuiw 1’were significantly decreased, whereas WLR was significantly increased （P〈0.05）. Correlation analysis showed that WLR was negatively correlated with RWC and TQ, with correlation coefficients of -0.85 and -0.73, respectively, whereas RWC was positively correlated with TQ, with a correlation coefficient of 0.70. Principal component analysis indicated three principal components, which could account for 91.79% of the total change. Membership function and hierarchical cluster analysis showed that ecotypes CP52, CP15, CP51, and CP49 had the best salt tolerance and were expected to be applied in the turf development of coastal saline soil.