海桑属红树植物离子积累、光合和抗氧化能力及相关性分析

以海桑属（SonneratiaLinn.f.）红树植物无瓣海桑（S.apetalaBuch.-Ham.）、海桑也S.caseolaris（Linn.）Engl.页、杯萼海桑（S.albaSmith）、卵叶海桑（S.ovataBacker）、拟海桑（S.×gulngaiN.C.DukeetB.R.Jackes）和海南海桑（S.×hainanensisW.C.Koetal.）为研究对象,比较了根际土壤和叶片中离子含量以及叶片光合和叶绿素荧光参数、叶绿素含量、抗氧化酶活性和O-·2产生速率的差异,并分析了叶片中Na＋和Cl-含量与部分生理生化指标的相关性。比较结果表明：海桑和拟海桑叶片中K＋含量最高、Na＋和Cl-含量均显著低于其他种类,但它们的根际土壤中Na＋和Cl-含量却较高。供试6种植物中仅海桑叶片对Cl-的富集系数小于1,各供试种类对K＋、Na＋、Cl-、Ca2＋和Mg2＋的富集系数均大于1；无瓣海桑对离子的富集系数由大至小依次为Mg2＋、K＋、Ca2＋、Na＋、Cl-,其他种类对离子的富集系数由大至小均依次为K＋、Ca2＋、Mg2＋、Na＋、Cl-。无瓣海桑和海桑的chla、chlb和总叶绿素含量差异不显著,但均高于其他种类；供试种类的chla/chlb比值均约为3,可能与海桑属植物为阳生植物有关。无瓣海桑的Pn、Tr和Gs均最高,而杯萼海桑的Pn、Tr和Gs均最低,但6种植物的Ci无明显差异。供试种类的Fv/Fm、qP、ETR和ΦPSⅡ均无显著差异,仅部分种类间的NPQ差异显著。无瓣海桑叶片中SOD、CAT和POD活性均显著高于其他种类,但O-·2产生速率最低；而卵叶海桑叶片中O-·2产生速率最高,其APX活性也均显著高于其他种类。相关性分析结果表明：供试6种植物叶片中Na＋和Cl-含量与Pn、qP、ΦPSⅡ和ETR负相关,与NPQ及SOD、CAT、APX和POD活性正相关。其中,Na＋含量与qP、ΦPSⅡ、ETR和SOD活性极显著相关,与NPQ和CAT活性显著相关；Cl-含量与SOD活性极显著相关,与qP、ΦPSⅡ和ETR显著相关。研究结果表明：供试海桑属植物对高盐生境有不同的耐性机?

Analyses on ion accumulation,photosynthetic and antioxidant capacities and their correlations of mangrove plants in Sonneratia

Taking mangrove plants of Sonneratia apetala Buch. -Ham., S. caseolaris （Linn.） Engl., S.alba Smith, S. ovata Backer, S. × gulngai N. C. Duke et B. R. Jackes and S. × hainanensis W. C. Ko et al. in Sonneratia Linn. f. as investigation objects, differences in ion content in rhizosphere soil and leaf and differences in photosynthetic and chlorophyll fluorescence parameters, chlorophyll content, antioxidant enzyme activity and O · 2 production rate in leaf were compared, and correlations of Na＋ and Cl--contents in leaf with some physiological and biochemical indexes were analyzed. The comparison results show that K＋ content in leaf of S. caseolaris and S. × gulngai is the highest and Na＋ and Cl- contents in their leaf are significantly lower than those of other species, but Na＋ and Cl- contents in their rhizosphere soil are higher. In these six species, enrichment coefficient of leaf to Cl- is lower than 1 only in S. caseolaris, while that of leaf to K＋, Na＋, Cl-, Ca2＋ and Mg2＋ in all species are higher than 1. Order of enrichment coefficient of S. apetala to ions from big to small is Mg2＋, K＋, Ca2＋, Na＋, Cl-, while that of other species is K＋, Ca2＋, Mg2＋, Na＋, Cl-. Differences in chla, chlb and total chlorophyll contents between S. apetala and S. caseolaris are not significant but are higher than those of other species. Ratios of chla / chlb of all species all are about 3, it may be related to Sonneratia species belonging to heliophyte. Pn, Tr and Gs of S. apetala all are the highest, while those of S. alba all are the lowest, but there is no obvious difference in Ci among all species. There is no significant difference in Fv / Fm, qP, ETR and ΦPSII among all species, there is significant difference only in NPQ among some species. SOD, CAT and POD activities in leaf of S. apetala all are significantly higher than those of other species, but its O 2 production rate is the lowest; while O ·-2 production rate of S. ovata is the highest, and its APX ·-activity is also signific