Compartive Evaluation Of Turf Quality,Salt Tolerance And Drought Tolerance Of9Cultivars Cool-season Turf-grasses

The trial materials include9cultivars cool-season turf-grasses:3Perennialryegrass(Regal5,Esquire,Double4N),3Tall fescue(Rhizing-star, Houndog6,Canavaro),3Kentucky Bluegrass (Merit, Rhythm, Rhapsody), which come from DLF group China. Thisstudy evaluated salt tolerance and drought tolerance during seedling stage, as well as turfquality among these9cultivars. The studies as follow:(1) Salt tolerance: To investigate which turf cultivars was more adaptive to high saltconcentration stress during seedling stage,6different NaCl contents was used to simulate saltstress (0,0.5%,1.0%,1.5%,2.0%,2.5%). We measured the seed germination parameter andseedling physiological: germination potential, germination rate, seed injury rate, the seedlingplumle length, radicle length, seedling electric conductivity, proline content, diversity solublesugar content. Through comparison of all indexes by membership function, the sequence ofsalt tolerance about9cultivars as follow: Double4N>Esquire>Regal5, Houndog6>Canavaro>Rhizing-star, Merit>Rhapsody>Rhythm. Through the correlation regressionrelationship to the seed relative germination rate and NaCl concentration stress, we calculate9cultivars germination adequate NaCl value: Double4N≤1.95%, Esquire≤1.37%, Regal5≤1.19%; Rhizing-star≤1.25%, Houndog6≤1.44%, Canavaro≤1.41%; Merit≤0.60%,Rhythm≤0.49%, Rhapsody≤0.64%.(2) Drought tolerance: To acknowledge which turf variety seed is more adaptive to highdrought osmotic stress during seedling stage, we used6PEG-6000contents to simulatedrought stress (0,5%,10%,15%,20%,25%).Through measured the seed germinationparameter and seedling physiological germination potential, germination rate, seed injury rate,the seedling plumle length, radicle length, seedling electric conductivity, proline content,diversity soluble sugar content. Through comparison of all indexes by membership function,the sequence of drought tolerance for9cultivars as follow: Double4N>Esquire>Esquire,Houndog6>Canavaro>Rhizing-star, Merit>Rhythm>Rhapsody. Duringthe correlation regression relationship to relative germination rate and PEG osmotic stress, wecalculate9cultivars germination osmotic adequate value(MPa):Double4N≥-0.90,Esquire≥-0.48, Esquir≥-0.50; Rhizing-star≥-0.25, Houndog6≥-0.60, Canavaro≥-0.39;Merit≥-0.36, Rhythm≥-0.22, Rhapsody≥-0.18.(3) Turf grass quality: To investigate which turf variety is more suitable in Yangling, wesowed every grass cultivars in field. We measured the seed germination and seedling growth speed and ability, the grass parameter indexs, and the turf performance through growingseason in2013. Through comparison of all indexes by membership function, the sequence ofgrass quality to9cultivars as follow: Double4N>Esquire>Esquire, Houndog6>Canavaro>Rhizing-star, Merit>Rhythm>Rhapsody.(4) Base on the9cultivars cool-season turf-grasses performance about salt tolerance,drought tolerance and the turf-grass quality. In addition combining the climate and soilcondition we consider that only5cultivars were suitable in Guanzhong area: Double4N,Houndog6, Canavaro, Merit, Rhythm.(5) Through analysis9culitivars turf-grasses ability of salt tolerance and adequate slatvalue, drought tolerance and adequate osmotic potential value relationship, we can see aswell the culitivars has heigh ability of salt tolerance and drought tolerance, as the culitivars’adequate salt value and adequate osmotic potential value performance was well. Thus we canused adequate salt value and adequate osmotic potential value evaluate the turf-grassculitivars ability of salt tolerance and drought tolerance.