Study On Screening Of Cool-Season Turfgrass Cultivars And Mixed Compositions For Saline Soil

Salinity effects on turfgrass germination and short梩erm (3 mth) performance of turf mixtures were studied under laboratory and field condition, respectively. The germination percentages of six turf grass species were observed at varying salt concentrations between 0.0 and 16000 mg kg?NaC1. Turfgrasses of various salt-tolerance levels were mixed up to grow in salinized soil. Germinating date.. seedling growth and establishing rate biomass underground~ quantities of tillers and plants covering uniformity and color were measured during the research period. Also, turf quality was evaluated by use of the correlation method of the Grey Systematic Theory. Results of the germination test showed that total germination declined linearly as salt level increased. Salt concentrations for germination percentage as 75%~50%and 25% of the control indicated that weeping alkaligrass (Puccine]lia distans(L.) Pan.) was most tolerant, perennial ryegrass (Lo]ium perenne L.) and creeping red fescue (Festuca rubra L.) better, followed by tall fescue (Festuca arundinacea shreb.), and creeping bentgrass (Agrostis pauses Huds.) and Kentucky bluegrass (Poa ,pratensis L.) sensitive. Field results suggested that perennial ryegrass and creeping red fescue were valuable as protectionrass for maintaining grass cover in saline soil, and with early germination and rapid growth rate could produce moist and shady micronvironments to prevent salt concentration in the soil solution, thus benefited the sensitive turfgrass. While weeping alkaligrass, the most salt tolerant during germination and early growth stage, grew slower than perennial 32 ryegrass and creeping red fescue, thus not suitable as protection梘rass. The results showed, meanwhile, that most mixed composition produced better turf quality than that of weeping alkaligrass. These mixture stands displayed more vigor and maintained dark梘reen color. The optimium mixed compositions were as follows: (l)Perennial ryegrass 30%+Weeping alkaligrass 20%+Kentucky bluegrass 50%; (2)Perennial ryegrass lO%+Weeping alkaligrass 20%+Kentucky bluegrass 50%+Creeping red fescue 20%; (3)Perennial ryegrass 20%+Weeping alkaligrass 20%+Kentucky bluegrass60%; (4)Perennialryegrass 40%+Weeping alkaligrass 20%+Kentucky bluegrass40%: (5)Perennialryegrass 50%+Weeping alkaligrass 20%+Kentucky bluegrass30%: (6)Perennialryegrass l0%+Weeping alkaligrass 10%+Creeping bentgrass80%; (7)Perennialryegrass 20%+Vleeping alkaligrass 10%+Creeping bentgrass 70%.