干旱胁迫对地果幼苗形态与生理特性的影响

以地果组培苗为材料，选用盆栽控水试验法，设置正常供水（CK）、轻度干旱胁迫（W1）、中度干旱胁迫（W2）和重度干旱胁迫（W3）4个水分处理水平，探讨地果幼苗对不同土壤含水条件的响应和抗旱能力。结果表明，随干旱胁迫程度的增加和胁迫时间的延长，地果的根冠比、茎蔓长度和脯氨酸含量总体呈上升趋势，蒸腾速率和叶组织含水量呈下降趋势。一些指标呈现出波动趋势，叶片面积和胞间CO₂浓度分别呈现先升后降和先降后升的趋势，气孔导度呈现先降低后升高又降低的波动趋势。超氧化物歧化酶活性、过氧化物酶活性和可溶性蛋白含量在W1处理下呈上升趋势，W2和W3呈先升后降的趋势。叶绿素含量在W1处理下呈下降趋势，W2和W3呈先降后升的趋势。净光合速率在W1处理下呈先下降后升高达到峰值又降低的趋势，W2和W3胁迫下呈下降趋势。这些结果表明地果具有一定的耐旱性，可以抵抗轻度及短时间内中度干旱。

Effects of Drought Stress on Morphology and Physiological Characteristics of Ficus tikoua Seedlings

The responses and adaptabilities of Ficus tikoua seedlings to different soil water conditions were studied based on potted culture method.Four water supply levels were set up:normal supply (control),mild drought stress (W1),moderate stress (W2),and sever stress (W3).The results showed that with the increase of drought intensity and stress time,the root-shoot ratio,length of the vines and proline content of ground fruit all showed increasing trends.While the transpiration rate and leaf tissue water content showed decreasing trends.Some indexes showed fluctuation trends.The leaf area first increased and then decreased,and the intercellular CO₂ concentration first decreased and then increased.The stomatal conductance showed a fluctuation trend:decreased first,then increased,and decreased.SOD activity,POD activity and soluble protein content showed rising trends under W1,and a rising and decreasing trend under W2 and W3.The chlorophyll content decreased under W1,and decreased first and then increased under W2 and W3.The net photosynthetic rate decreased first,then increased to peak value and then decreased under W1,and decreased under the stress of W2 and W3.These results suggested that F.tikoua seedlings had a certain drought tolerance and could resist mild and moderate drought in a short time.