Effect of Low Temperature Stress on Physiological Process of Kentucky Bluegrass
LIANG Hui min 1,XIA Yang 1,DU Feng 2,ZHANG Pu jin 2 (1 Shandong Forestry Academy, Jinan 250014,China;2 Gansu Agricultural University,Lanzhou 730070,China)
Effects of low temperature stress on physiological process of Kentucky bluegrass ( Poa pratensis ) was investigated. The result showed that under 5℃ the stress activities of SOD and CAT increased with the stress time and reached the peak after 4 hours and them SOD and CAT increased with the stress time and reached the peak after 4 hour and then decreased. Under 0℃ and 6℃ enzyme activities decreased sharply and almost reached the zero. The enzyme activities of 6℃ decreased than that of 0℃. The chlorophyll and carotin contents decreased with the stress time and the lower of temperature was the faster it decreased. Under 5℃ the proline content remained unchanged and under 5℃ and 0℃ it increased significantly with the stress time. Under 5℃ and 0℃ membrane relative penetration remained unchanged and under 6℃ it increased significantly. The order of sensitivity to low temperature stress is SOD,CATcarotinprolinechlorophyllmembrane relative penetration.