Study On Salt And Shade Tolerance Of Warm-seasonal Turfgrasses

In potted plant experiment, physiological responses (growth, physiology, photosynthetic characteristics, nutritious element et al) soil salt stress were studied in three warm-seasonal turfgrasses: centipedegrass( Eremochloa ophiuroides), Zoysiagrass() and Malinagrass() . In field experiment, lawn-forming states and landscaping effect of five warm-seasonal turfgrasses (centipedegrass, zoysiagrass, malinagrass, Bernudagrass and Bernudagrass 'turf-green') under shaping conditions and physiological response of centipedegrass to shape). The results shows:Soil sail stressVisual performance of different turfgrasses differed remarkably under salt stress with different concentration. Centipedegrass performed died more swiftly than Zosiagrass and Malinagrass. For well visual performance, the befitting growth concentration of soil salt for centipedegrass should not exceed to 0.4%, while for zoysiagrass and malinagrass, the concentration should not exceed to 0.6%.With the increasing concentration of salt stress, dry weight of root, shoot and leaf trended to sustaining decline, in which extent of root declined more swiftly than that of shoot. Simultaneously, ratio of root to shoot (RSR) declined gradually with the increasing salt stress.Declining extent of biomass(especially of root dry weight) and performance of turfgrass(such as visual color) under stress of high concentration salt could estimate salt tolerance of turfgrass. Accordingly, ranking of abilities to salt tolerance were: Malinagrass > Zoysiagrass > Centepedegrass. Relatively, distinction between Zoysiagrass and Malinagrass was less.Activities of several protective enzymes(SCD CAT POD APX) of centipedegrass under 0.6%~0.8% salt stress declined gradually with the prolonging stress days, while the activities of protective enzymes increased in 0.2%~0.4% salt treatment of Centipedegrass and all the treatments of Zoysiagrass and Malinagrass. MDA content and RPP increased gently under the wild stress, while increased remarkably with the further stress. Activities of PAL changes similarly among three turfgrass, but under 0.8% salt stress, it increased in early phase of stress and decreased with the prolonging stress.In the extent of salt stress what the three turfgrasses could tolerate, root activities increased in early phase of stress and decreased with the prolonging stress, but in Centipedegrass, serious salt stress arose root activities continuously. With the increasing concentration of salt stress, saturation water deficiency increased gradually. Root activities and saturation water deficiency remarkably related to salt tolerance of turfgrasses.In three warm-seasonal turfgrasses under soil salt stress, soluble proline content increased in early phase of stress and decreased with the prolonging stress, but total Pro content increased continually with the deepened salt stress. Therefore, changing trend of Pro content under high concentration salt stress may estimate salt tolerance of warm-seasonal turfgrasses, accumulation of Pro could indicate salt stress degree.Content of Chla, Chla and total Chi declined in leaves of three warm-seasonal tufgrass under soil salt stress, and declining extent differed among three grasses, which could be used to estimate salt tolerance. Changes of soluble protein content increased at the early phase of stress and decreased with the prolonging stress (lower than control) under mild salt stress, which conformed among three turfgrasses. Soluble protein content declined successively under high concentration salt stress in centipedegrass, which were lower than the control during the whole stress.With the deepened salt stress, content of increased in root, leaf and stolon of three turf-grasses, and proportion of Na+ in shoot increased remarkably in three apparatuses. Under same concentration salt stress, in three apparatuses of Centipedegrass was higher than those of Zoysiagrass and Malinagrass. Difference of Na+ concentration between in Zoysiagrass and in Malinagrass was unremarkable., but under serious stress (0.8% salt treatment), Na+ conce...