A SDUDY ON DROUGHT RESISTANCE OF POPULUS HOPEIENSIS CUTTING STOCKS
Wang Shu-qing(Dept. of Basic Courses)Wong Jun-hua(Dept. of Forestry) Zhang Xue-min Li Qiang
The drought resistance of Populus hopeiensis cutting stocks from three different regions; Xi-Ning of Qinhai,province, Wu-Qi and Jia-Xian Counties of Shaanxi were investigated. It was found that the growth rate, drought resistance and photosynthetic activities of these three sources appear to be distinct variance. The expension growth of. leaf area, the stock height and the stem growth rate of the cutting stocks from Wu-Qi are all greater than those of the cutting stocks from Xi-Ning and Jia-Xian. Measureer ments of different physiological indices of drought resistance showed that the bound and free water ratio and the critical water saturation deficit of leaf tissues of the cutting stocks from Xi-ning are greater than those of the cutting stocks from Wu-Qi and Jia-Xian. It is suggested that the less the cell membrane Permeability of leaf tissues, the greater the dehydration resistance when water stress occurs, hence the lighter the damage to the cell membrane.