Studies On The Differences Of Temperature Stressed Tolerance And Mechanism In Diverse Turfgrass Species

The primary purposes of this study are to select the grass species and to study on the existent problem and the application status based on the climatic characteristics of lawn ecotone. Taking seven warm season adaping well and widely naturalized species of Hunan:Eremochloa ophiuroides,Seashore paspalum,Zoysia matrella (L.) Merr. Cynodon dactylon Linn. Pers,Tiffgreen 419,Zoysia japonicacv. Lantai No.3,Z. sinica Hance and ten cold season species:Barrera,Ikay,Vegas,Bridgeportâ…¡,Bartwingo,Accent,Wellow,Barrister Koala,Regent as the subject investigated. According to the change of physiological indicators of different grass species undertake temperature stressed, inquiry the potential applications, and the main conclusions as following:1. Made the turf charactors evaluation and analysis for each cold/warm-season turfgrass. The results showed that various species/varieties of turfgrass which have strong resistance appeared favorable turf charactors.2. Under the cold stressed, taking the content of soluble suge,chlorophyll content,MDA tontent,free proline content in leaves and leave electric conductivity as measuring indicators on seven grass species. The results show that under cold stressed condition, the physiological indexes of strong cold resistance grass species change slow, but the weak species changes quick comparatively. The soluble suger content,MDA content,proline content in leaves and leave electric conductivity content had positive relation to the cold stressed, the chlorophyll content had negative relation to it. According to the physiological indexes and the reality, concludes the cold resistance order that Cynodon dactylon Li. Pers >Eremochloa ophiuroides>Tiffgreen 419>Zoysia japonicacv. Lantai No.3>Z. sinica Hance>Zoysia matrella (L.) Merr.>Seashore paspalum.3. Determined the physiological indicators of 6 cold-grasses plant altogether 10 lawns grass varieties under high tempemperature stressed, the findings indicated that, the physiological indexes of different grasses and varieties had obviously difference among each grass species. Under high temperature stressed, the soluble suger content,MDA content,proline content in leaves and leave electric conductivity content had positive relation to the cold stressed, the chlorophyll content had negative relation to it. According to the physiological indexes and the reality, concludes the heat resistance order that Vegas >Barrera>Bridgeportâ…¡>Ikay>Koala>Barrister>Regent>Bartwingo>Accent> Wellow.4. According to the comparison test of the phiosiological indexes, leaves electric conductivity respond to the stress is most sensitive, the content of chlorophyll in leaves changes is the slowest. Analysis by synthesis through combining the content of chlorophyll,MDA,soluble suger,free proline in leaves and leave electric conductivity change, under the low temperature stressed, the cold resistance of Cynodon dactylon Li. Pers is better than other warm-seasons grass obviously; under high temperature stressed, the heat resistance of Vegas and Barrera are better than other cold-season grass. The results indicated that Vegas and Barrera (Fescue arundinacea SHreb.) had stonger heat resistance and Cynodon dactylon Li. Pers had stronger cold resistance which have certain utilized value.