Study On Soil Drought Stress On Two Spices Of Rhododendron

Azaleas are Rhododendron Ericaceae and its flower and leaf are beautiful,which is one of the world's top ten and were spent with a high ornamental value and landscape value.Because Rhododendron is strong adaptable,easy reproduction cultivation,less pest,robust growth,it has a very wide range of garden applications.Drought is one of the major abiotic stress factor affecting plant on the normal metabolism and growth,which is very important for China's urban greening and growth of crops.Therefore,this paper is researching drought-resistance of two different rhododendron species,that is Phododendron "belgium" and phododendron "hair".In the date of the first 0,3,6,9,12,15,18,21,24,27,30,33-day,stopping filling water with Phododendron "belgium" and phododendron "hair",the physiological and biochemical indexes about Phododendron "belgium" and phododendron "hair" were measured.In the first days of 27,30,33-day,restoring filling water with them,their physiological and biochemical indexes were measured again.By analysis different datas,we can study azaleas's drought resistance.The main conclusions are as follows:(1) Phododendron "belgium" and phododendron "hair" respond to a series of physiological response mechanism under drought stress.Through the determination of 13 kinds of physiological and biochemical indicators,we can judge drought resistance of Phododendron "belgium" and phododendron "hair". WC,RWC,water potential,PMP with the number of days of drought stress increased are gradually reduced;WSD,POD as the number of days of drought stress increased are an upward trend; Chl,APX as the number of days of drought stress increased are the first drop and in an upward trend at last;protein content,CAT as drought stress increase in the number of days are the first increaseand in a downward trend at last.(2) Phododendron "belgium" and phododendron "hair" after rehydration in the date of the first 27,30,33-day will also respond to a series of physiological mechanisms.Through the determination of 13 kinds of physiological and biochemical indexes,this eassy judges recovery of Phododendron "belgium" and phododendron "hair". From thirteen indicators,including the WC,RWC,water potential and so on,this essay finds that metabolic physiology and biochemistry after drought and rewatering has been a certain degree of recovery and the greater the intensity of drought stress,the weaker recovery.(3) By a comprehensive evaluation of drought resistance indicators(factor analysis),we can evaluate the drought resistance of Phododendron "belgium" and phododendron "hair".The result shows that the drought resistance in Phododendron "belgium" is stronger than phododendron "hair".