Evaluation On The Heat Resistance Of The Cool-season Turf Grass And The Induction And Screen Of Heat-resisting Mutants

As its long green period and the characteristics such as being beautiful of grass color, the cool-season turfgrass more and more obtains people's favors, but the high temperature in summer is a primary factor of restricting its unable be popularized and used in such transition climatic zone areas as Hunan province, etc. To enhance the cool-season turfgrass heat resistance and to cultivate new variety, can offer powerful technical support for the transition climatic zone area of lawn construction, have very important meanings. The research based on observing and investigating the Changsha city cool-season lawn, through determination of heat resistance index, some heat resistance better varieties were screened. Then the L-93 variety was dealt with EMS. The research explored the way of lawn grass treated by EMS at the same time the treated materials were determined and analyzed preliminary. Each part of experimental result as follows:1. The outdoors investigating of cool-season turfgrass heat resistance.The thermal stability observation result of the cool-season turf grass of outskirts proving ground is: According to the level of turning green the thermal stability have big difference among the genera. of cool-season turf grass. :the Poa's turning green rate is 10%~45%, the Acrostic's turning green rate is 30%, the Festuca and Linoleum s turning green rate is less than Poa and Acrostic's. The heat resistance permutation order is: Poa > Acrostic > Festuca > Linoleum, The Park, Kenblue, Blue Knight belongs to Poa have the distinct advantage.Indicated to the city13 different functions green place investigation result that cool season lawn developed very fast in recent years, it has accounted for 23% in the green land investigating. But the high temperature in summer is still a main factor of influencing their growth. The reasonable seed selection and the maintenance management can affect the cool-season lawn of view too to a great extent. But at last the fundamental way to solve the problem is screening and cultivating heat-resisting properties cool-season turfgrass variety.2. Heat-resistance evaluation of the cool-season turf grassThe leaves treated with dry heat then the conductivity of leaves was been mensurated to appraise the heat resistance among the ten kinds of turf grass. The experimental result is: The young tender material of cool-season turf grass bears the dry heat obviously to be lower than the mature material; The thermally endurance in different genus is prominent. For seedling: Linoleum > Festuca > Poa > Acrostic. For mature tested turf-grass: Festuca > Poa > Linoleum > Acrostic. The paper selected five varieties have high heat resistance including Poa: Blue moon, Freedom2; Linoleum: Accent; Festuca: Houndog5; Acrostic: L-93.