摘要
选用4个不同产地披针叶茴香(Illicium lanceolatum)(浙江临安(LA)、浙江开化(KH)、江西武宁(WN)和福建南平(NP))1年生盆栽幼苗为试验材料,设置3个光照处理(Ⅰ:25μmol·m-2·s-1;Ⅱ:50μmol·m-2·s-1;Ⅲ:75μmol·m-2·s-1)和2个水分处理(正常供水(CK)和自然干旱2d),探讨弱光环境下短期干旱对披针叶茴香幼苗生理特性及适应性的影响。结果表明:两种水分处理下,披针叶茴香幼苗抗氧化酶活性和渗透调节物质含量对弱光的敏感性存在明显差异。在光处理Ⅱ和Ⅲ条件下,WN产地幼苗经2d水分胁迫后,过氧化氢酶(CAT)活性比正常水分条件明显增加,过氧化物酶(POD)活性在光处理Ⅲ下比正常水分条件的显著增加,各光处理下超氧化物歧化酶(SOD)活性比正常水分的显著下降,丙二醛(MDA)含量相反。水分胁迫后,各光处理下LA产地幼苗的SOD和POD酶活性低于正常水分条件的,可溶性蛋白和MDA含量均较正常水分处理的增加。与正常水分条件相比,水分胁迫后的KH产地幼苗SOD、POD和CAT酶活性在光处理Ⅰ下均显著增加,可溶性蛋白和MDA含量有所下降。NP产地幼苗各光处理的酶活性均表现出水分胁迫后的比正常水分下的有所提高。可知,短期水分胁迫对提高KH、WN和NP产地幼苗对弱光环境的适应性具有显著促进作用。研究揭示短期水分胁迫可通过增加抗氧化酶活性和渗透调节物质含量来提高幼苗对弱光的适应性。
Low availability of soil moisture is considered a major limiting factor for plant growth and crop yield worldwide, and it turns to be a more serious problem under the context of global change. A weak light stress, resulting from significantly lower light intensity than light saturation point of plant in long time, will affect the morphogenesis and physiological and biochemical processes of plant. The Chinese anise （Illicium lanceolatum）, a traditional medicinal plant in China, has high content of shikimic acids which have effects of antiphlogosis and analgesis, and can reduce platelet aggregation and suppress vascular and cerebral thrombosis. Shikimic acid can also be an intermediate for antivirus and anticancer drugs. Scattering in its natural habitats, I.lanceolatum resources have experienced a rapid decline due to overexploitation. Therefore, it is necessary to study the protection and development strategies of I.lanceolatum resources. Soil moisture and light intensity are important restrictive impact factors for growth and biomass accumulation of I.lanceolatum seedlings. Until now, there is no reports about the mechanism of this species＇ response to water and light conditions. In order to explore the effect of short-term drought on the plant physiological characteristics and its adaptive capacity under low light intensity, a pot experiment was conducted with one year old I.lanceolatum seedlings for four ecotypes, respectively ecotypes from Linan Zhejiang （LA）, Kaihua Zhejiang （KH）, Wuning Jiangxi （WN） and Nanping Fujian （NP）, treated under three low light intensity （Ⅰ：25μmol·m-2·s-1;Ⅱ：50 μmol·m-2·s-1;Ⅲ：75 μmol·m-2·s-1） and two water supply levels （normal water supply and watering after 2 days drought）. The results showed that the sensitivity of antioxidant enzymes activity and osmotic substances contents of I.lanceolatum seedlings to low light intensity was significantly different between two water supply conditions. After 2 days＇ dought, catalase （CAT） activity of WN ecotype seedlings in the light treatments of Ⅱ and Ⅲ significantly increased compared with that under normal water condition, the peroxidase （POD） activity in the light treatments of Ⅲ also significantly increased, and the malondialdehyde （MDA） contents in all three light treatments increased while the superoxide dismutase （SOD） activity decreased. Under the water stress, the SOD and POD activity of LA ecotype seedlings in all light conditions were lower than those under normal water supply, and the soluble protein and MDA contents were higher. Compared with normal water supply, the SOD, POD and CAT activity of KH ecotype seedlings in the light treatment of Ⅰ increased significantly under water stress, while soluble protein and MDA content decreased. The enzymes activity of NP ecotype seedlings in all light treatments increased after short-term water stress. We concluded that the water stress can significantly promote the adaptability to weak light for KH, WN and NP ecotypes seedlings by increasing antioxidant enzymes activity and osmotic substances contents. This result will provide the theoretical foundation for ex-situ conservation, efficient cultivation, soil moisture and light condition management of I.lanceolatum.
出处
《生态学报》
CAS
CSCD
北大核心
2014年第4期814-822,共9页
Acta Ecologica Sinica
基金
浙江省科技计划资助项目(2009C32097)
关键词
披针叶茴香
不同产地
弱光
水分胁迫
抗氧化酶
渗透物质
Illicium lanceolatum
ecotypes
low light stress
water stress
antioxidant enzyme activities
osmotic regulation substances
