Evaluation of salinity tolerance of 55 centipedegrass ecotypes

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.