湿度对铁皮石斛幼苗生长及光合作用的影响

Effect of Humidity on Photosynthesis of Dendrobium officinale

为了探究湿度对铁皮石斛幼苗生长光合作用的影响，采用Li-6400便携式光合仪研究了2种湿度（80％以上和60％～70％）下不同温度和光照强度对铁皮石斛幼苗生长的影响。结果表明：当光照为240μmol／（m2·S）时，无论温度为25℃、20℃、15℃，铁皮石斛幼苗在湿度为80％以上时其光合速率值明显高于湿度为60％～70％的测量值；当温度为25℃，光照强度为360μmol／（m2·S）时，其在2种湿度条件下的光合速率变化并不明显；光照强度为120μmol／（m2·S）时，则表现为高湿度光合速率值明显比低湿度的大，且第二峰值也大。

In order to measure the effect of humidity on photosynthetic rate ot D. officinale seedlings, The Li-64000 photosynthesis systems was used to study the effect of different temperature and light intensity on seedling growth under different humidity. The result showed that the photosynthetic rate of 80% humidity was obviously higher than that of 60 %- 70% humidity at light intensity od 240 mol/ （m2. s） regardless of 25℃, 20℃ and 15℃ When the temperature was 25℃and the light intensity was 360 t,mol/（m2 . s）, the change of photosynthetic rate for the two different humidity had no significant difference. The photosynthetic rate of higher humidity is higher than that of lower humidity under the lilzht intensity of 120 umol/（mz.s） and the second peak was also higher.