| The field adaptation of K.cristata(L.) Pers was reviewed in June to September,2005 and May to November,2006;In March to November,2006 and the same time of 2007,the turf quality of K.cristata under cultivated condition in Hohhot was evaluated;The characteristics of physiological ecology and water-use of K.cristata under controlled soil moisture,and,the drought resistance of K.cristata under 100%FC was studied in March to November,2007.The results suggested that:The ecological adaptation scope of K.cristata was so wide that it could live in almost each state except the desert,the Steppificated Desert and the cold temperature coniferous forest region in Inner Mongolia.Under cultivated condition,K.cristata turned green in the early of march,its multiply growth began in the late of April,it blossomed in the late of May,its seed matured in the middle to late of June,it stopped growing in the middle of November in Hohhot,the green-up period was about 250d;its grass height was not more than 60.2cm.its tuft height was about 13.4cm After transplanting and adapting,the dynamic of tiller number of K.cristata was tendency of "M".In winter,it could also grow at the hard cold condition,its tiller number of regreen was 31/clump more than that of the last year.The photosynthesis ability of K.cristata was stronger than that of the CK(Poa pratensis),the average photosynthesis of K.cristata was 0.42～5.77μmolm-2s-1 bigger than that of the CK,the average transpiration of it was 0.35～1.28 mmolm-2s-1 bigger than that of the CK,the instantaneous water-use efficiency was 0.72～0.97μmol CO2/mmol H2O bigger than that of the CK.Under the same standard of evaluation,the score of K.cristata was 6.14～7.86,the score of the CK was 4.43～6.69.In the fall when the CK was unwell,the performance of K.cristata was quite better.The resistance of K.cristata was better than the CK.Under -3℃,few of young tillers were frozen,but the population did not change much.It responded slowly to drought.Its disease resistance,harmful insect resistance was better than the CK.Under controlled soil moisture,the tuft height,the grass height,the leaf width and the biomass of K. cristata reduced when the moisture has dropped,but its root/shoot ratio has enlarged.Its tuft height was between 0.52 to 9.21cm,its grass height was between 2.61 to 12.38cm,its leaf width was between 0.1 to 0.2cm.Its degree of coverage at 40%FC was the biggest in the three treatment.The evapo-transpiration enlarged when the moisture has been increase,and it's remark for the evapo-transpiration in soil moisture.At 60%FC,K.cristata could save 293.49mm water,the ratio was 60.93%,at 40%FC,it could save 212.71mm 293.49mm water,the ratio was 54.13%,at 20%FC,it could save 52.31mm water,the ratio was 16.03%,and the evapo-transpiration at 40%FC could save 88.72mm water than that at 60%FC,the ratio was 22.58%.It's possible for K.cristata to be turf at 40%FC,also,it could save mach water at that level.At 40%FC, beside the rain,it needed 53.74mmwater in June,43.64mm water in July,76.91mm water in August, 43.09mm water in September,the total was 217.39mm.Began from 100%FC,with evapo-transpiration,30%degree coverage of K.cristata needed 18d to get to temporary wilting,when the soil moisture was 15.12%,after 21 day's transpiration,it became temporary wilting,then the soil moisture was 7.06%.Only with evapo-transpiration it could live 35±1.1d,Only with transpiration,the time was 44±2.2d.Its wilting coefficient was 0.064,while that of the CK was 0.093,so it could use the water in soil more fully,and could resist drought better.
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