不同光照下土壤水分胁迫对长苞铁杉幼苗的作用

Effects of water stress on Tsuga longibracteata seedlings under varied light intensity.

于2004—2005年研究了在不同光照下(100%、50%、25%、10%全日照)水分胁迫(土壤含水量30%、25%、20%、15%)处理30 d后的长苞铁杉幼苗存活率、叶片光合色素含量及比例、MDA含量、SOD活性、POD活性和Pro含量的变化.结果表明:在光照与土壤干旱协同作用对幼苗的影响方面,强光照(100%全日照)加重了干旱对幼苗的伤害,遮阴可以降低不利因素的影响;在光照与土壤过湿协同作用对幼苗的影响方面,强光照(100%全日照)和弱光照(10%全日照)加重了土壤水分过多引起的伤害,中等强度光照(50%和25%全光照)可以降低不利因素的影响;在50%和25%全日照条件下,长苞铁杉幼苗对土壤水分过多和干旱胁迫的忍耐能力较强.

The seedling＇s livability, SOD activity, POD activity, content of photosynthetic pigment, MDA and Pro in the seedling leaves of Tsuga longibracteata were studied after being planted for 30 days at four different water content（30%, 25%, 20%, 15%） under four light intensity environment（100%, 50%, 25%, 10% full day light） from 2004 to 2005. The results showed that high light intensity（100% full day light） could enhance the injury of soil drought on seedlings of T. longibracteata, while shading could reduce it. Both high light intensity（100% full day light） and low light intensity（ 10% full day light） could enhance the injury of excessive soil water on the seedlings of T. longibracteata, but medium light intensity（50% and 25% full day light） could reduce it. Under medium light intensity（50 % and 25 % full day light） environment, the tolerance of seedlings of T. longibracteata on soil water stress was high.