摘要
消落带人工植被的筛选与重建是三峡库区消落带生态治理的重要措施之一。为筛选更多适合消落带植被构建与时空更替中耐水淹的物种,选择三峡库区(万州段)消落带退水期存活的4种乡土草本植物进行水淹和恢复的处理,测定光合及生理生化指标,调查它们短期水淹胁迫的响应机制。结果表明:1)鱼腥草和马兰在水淹15 d后地上部分陆续坏死,酸模和苍耳地上部分存活在22 d左右,苍耳在水淹和恢复的环境中根系长度显著增长;2)水淹15 d后,酸模脯氨酸(Pro)质量分数、超氧化物歧化酶(SOD)、过氧化氢酶(CAT)活性及根系活力(TTC质量分数)与对照相比都有显著上升,恢复15 d后净光合速率(P_(n))、蒸腾速率(T_(r))、丙二醛(MDA)质量摩尔浓度、TTC质量分数、可溶性糖质量分数及抗氧化酶活性与对照相比都有明显上升;3)水淹15 d后,苍耳MDA质量摩尔浓度、Pro质量分数、SOD、CAT及TTC质量分数与对照相比都有显著上升,特别是Pro和TTC质量分数与对照相比达到了极显著差异,恢复15 d后P_(n)、气孔导度(G_(s))、Pro质量分数、SOD、CAT活性及TTC质量分数与对照相比也有显著上升;4)水淹15 d后,鱼腥草P_(n)、胞间CO_(2)浓度(C_(i))、CAT与对照相比有上升,恢复15 d后所有测定指标与对照相比没有显著变化。5)水淹15 d后,马兰的C_(i)、G_(s)、TTC和Pro质量分数、CAT活性与对照相比都有显著下降,而MDA与SOD值有显著上升。说明短暂水淹后苍耳和酸模主要通过增强根系活力、提高抗氧化酶活性及Pro质量分数来调节水淹胁迫,并且在恢复处理后光合指标与根系活力都有较大程度的激发与增强,表现出水淹灵敏型或高耐水淹性,可以适应短期水淹胁迫;而鱼腥草在水淹后光合指标明显下降,生理方面没有较及时的响应,表现出对水淹胁迫的迟钝性;马兰通过降低根系活力来维持根系在缺氧环境中的能量平衡,表现出低耐水淹。
[Background]Screening and restoration of artificial vegetation is one of the important measures to control the ecological environment of the water-level-fluctuating zone of the Three Gorges Reservoir Area.In order to select more flood-resistant species suitable for vegetation construction and temporal spatial replacement,4 indigenous herbaceous plants,Houttuynia cordata,Rumex acetosa,Kalimeris indica and Xanthium sibiricum)from the Three Gorges Reservoir(Wanzhou section),surviving in the recession period were taken to our experimental station for investigating their response mechanisms to short-term submerging stress.[Methods]Above 4 plants were treated for pot submerging and restoring experiment lasting 30 d.The plants were randomly divided into 3 groups of each 10 pots,CK group was under nature outside and no more adding water,the submerged group was watering until the top of plants,and the submerged+restored group was first 15 d submerged and later 15 d under natural outside condition.Morphological,photosynthetic and physiological and biochemical indices were measured at first day,15 d,and 30 d respectively.The result data were processed by SPSS19.0 and One-way ANOVA.[Results]1)The aboveground parts of H.cordata and K.indica were successively necrotic after 15 d of submerging,the aboveground parts of R.acetosa and X.sibiricum were survived for about 22 d,and the root length of X.sibiricum increased significantly in the environment of submerging and restoring.2)After 15 d of submergence,the contents of proline(Pro),superoxide dismutase(SOD),catalase(CAT)and root activity(TTC content)of R.acetosa increased significantly compared to CK.After 15 d of restoring,net photosynthetic rate(P_(n)),transpiration rate(T_(r)),malondialdehyde(MDA),TTC,soluble sugar content and antioxidant enzyme activity increased significantly compared to CK.3)After 15 d of submergence,MDA content,Pro content,SOD,CAT activity and TTC value of X.sibiricum increased significantly compared to CK,especially the values of Pro and TTC reached a very prominent difference.After 15 d of restoring,P_(n),stomatal conductance(G_(s)),Pro content,SOD,CAT activity and TTC value increased notably.4)After 15 d of submergence,P_(n),intercellular CO_(2) concentration(C_(i)),CAT activity of H.cordata increased compared to CK,but no significant changes were observed after 15 d of restoring.5)After 15 d of submergence,C_(i),G_(s),TTC,Pro,CAT of K.indica decreased drastically,MDA and SOD increased significantly.[Conculsions]The results indicated that X.sibiricum and R.formosana regulated the submerging stress mainly by enhancing root activity,antioxidant enzymes activity and Pro content,and the photosynthetic indexes and root activity were stimulated and enhanced after restoring,showing they were sensitive to submerging or had high submerging-tolerance.The photosynthetic index of H.cordata decreased significantly and no timely response in physiological aspect after submergence,showing it was insensitive to submerging stress.K.indica maintained energy balance of root system in anoxic environment by reducing root activity,showing it had lower submerging-tolerance.
作者
钟彦
唐恒
田辉
甘丽萍
ZHONG Yan;TANG Heng;TIAN Hui;GAN Liping(Teacher School of Education College, Chongqing Three Gorges University, 404100, Chongqing, China;Biological and Food Engineering, Chongqing Three Gorges University, 404100, Chongqing, China)
出处
《中国水土保持科学》
CSCD
北大核心
2021年第6期115-124,共10页
Science of Soil and Water Conservation
基金
重庆科委项目“三峡库区消落带良木水桦水淹条件下的生理响应与转录组分子机制印射关联”(cstc2019jcyj-msxm1218)
重庆市教委项目“渝东北金桂资源快速再生体系构建”(KJ1710246)
重庆市教委项目“三峡库区消落带竹柳(Salix hybrid)水淹胁迫下的差异基因筛选”(KJQN202101244)。
关键词
乡土植物
水淹胁迫
消落带
三峡库区
indigenous plants
submerging stress response
water-level-fluctuating zone
Three Gorges Reservoir Area
