摘要
模拟三峡库区消落带土壤淹水变化特征,设置常规生长水分条件(CK)、轻度干旱水分胁迫(T1)、土壤水饱和(T2)以及水淹(T3)4个处理组,研究池杉当年实生幼苗根系的苹果酸、莽草酸含量以及生物量变化(均以干质量计)。结果表明:T1、T2和T3这3组池杉幼苗主根的苹果酸、莽草酸含量以及生物量均未与CK组达到显著性差异;T2和T3组侧根苹果酸平均含量分别显著高出CK组1.7和2.2倍,总根苹果酸平均含量显著高于CK组0.8和1.5倍;T1组的侧根、总根苹果酸平均含量与CK组均未达到显著差异;与侧根苹果酸的变化类似,T2和T3组侧根莽草酸平均含量分别高出CK组0.4和1.1倍,这与T1组低于CK组0.5倍形成鲜明对比;T2和T3组总根莽草酸平均含量虽也分别高出CK组,但并未与之达到显著差异的程度,与T1组总根莽草酸含量显著低于CK组0.3倍形成鲜明对比;T2和T3组主根、侧根和总根生物量分别均未与CK组达到显著差异,但T1组的侧根、总根生物量却显著高于CK组。相关性分析表明:池杉总根苹果酸与莽草酸含量表现出极显著的正相关(P<0.01);总根莽草酸含量与总根生物量之间则表现出显著的负相关性(P<0.05)。
In simulating soil submergence in the hydro-fluctuation belt of the Three Gorges Reservoir Region, four different kinds of water treatment were applied to investigate the change in malic acid, shikimic acid, and biomass in the roots of Taxodium ascendens seedlings （all data being calculated in dry mass）. The main purpose respectively of this study was to explore the mechanism of the plant＇s metabolic adaptation to water level changes. The four water treatments respectively were： normal growth water treatment （CK）, light drought water stress （T1）, soil water saturation （T2） and soil submersion （T3）. The results showed that there was no significant difference in content of malic acid and shikimic acid, and in biomass in the taproot between CK and T1, T2 or T3. The content of malic acid in the lateral root in both T2 and T3 was 1.7 and 2.2 times higher than that in CK. Furthermore, the average content of malic acid in the whole root system in both T2 and T3 was also 0.8 and 1.5 times higher than in that of CK. However, the mean content of malic acid in the lateral root or whole root in T1 was not significantly different from that in CK. Compared to CK, the mean content of shikimic acid in the lateral root in T2 and T3 increased by 0.4 and 1.1 times respectively, whereas that in T1 was 0.5 times less than that in CK. Although the mean content of shikimic acid in the whole root system in T2 and T3 respectively appeared higher than that in CK, no significant difference with CK was found. On the contrary, T1 significantly exhibited a 0.3 times lower in mean content of shikimic acid in the root system than CK. In comparison with CK, both T2 and T3 demonstrated no significant differences in biomass of the taproot, lateral root and the whole root system, respectively, but T1 showed a significant increase in biomass of the lateral root and the whole root system. A highly positive relationship was displayed between mean content of malic acid and mean content of shikimic acid in the whole root system （ P 〈 0.01）. The mean content of shikimic acid in the whole root system was negatively correlated with the biomass of the whole roots （ P 〈 0.05）.
出处
《林业科学》
EI
CAS
CSCD
北大核心
2008年第10期1-7,共7页
Scientia Silvae Sinicae
基金
重庆市自然科学基金重点资助项目(CSTC-2008BA7032)
国家自然科学基金资助项目(30370279)
三峡库区生态环境教育部重点实验室自由探索研究基金
三峡库区森林生态保护与恢复重庆市市级重点实验室开放基金
教育部“春晖计划”项目(Z2004-2-55001)资助
关键词
土壤淹水变化
池杉幼苗
苹果酸
莽草酸
生物量
消落带
三峡库区
soil dynamic submergence
Taxodium ascendens seedlings
malic acid
shikimic acid
biomass
Three Gorges Reservoir Region
hydro-fluctuation belt
