铅处理对含羞草种子萌发及幼苗生长的影响

采用不同浓度的醋酸铅[Pb(CH_3COO)_2·3H_2O]溶液对含羞草种子进行萌发处理,结果表明,不同浓度铅对含羞草种子萌发和幼苗生长均存在着抑制作用,且抑制程度随着浓度的提高而增加;铅胁迫对含羞草幼根生长具有显著的抑制效应,根长的变化可作为植物受重金属毒性影响的一个重要指标;幼苗的生长状况比种子萌发更能体现铅毒性的危害程度.     

不同栽培方式对含羞草生长发育与生理特性的影响

研究了水培、基质、土壤栽培方式对含羞草的生长发育及生理特性的影响.结果表明:水培能为含羞草的生长发育提供良好的生长环境,其植株鲜重、叶片数、株高和冠幅等指标均高于基质栽培和土壤栽培,且达到极显著水平;水培含羞草的根系活力最强,与土壤栽培相比达到极显著水平.     

动作电位控制的韧皮部物质卸出

对于敏感植物如含羞草(Mimosa pudica),当触摸叶片时,能激起叶枕运动细胞的膨压降低,动作电位上升,导致叶片合拢,刺激后,这些电位通过韧皮部运输对叶枕韧皮部物质卸出产生影响.利用放射性自显影的方法通过“C 物质(CO_2)观察韧皮部的位置,在未受刺激的叶枕,放射性物质显示的图象仅在韧皮部;然而,刺激后的叶枕~(14)C 物质主要集中在皮层的可伸长区域.由于刺激产生动作电位,因而认为,叶枕动作电位导致韧皮部糖类物质卸出.     

四种化学物质处理对无刺含羞草种子发芽率的影响

无刺含羞草种子经四种化学物质处理后的萌发实验表明，5%HCl溶液对种子萌发几乎无影响，0.2%KNO3溶液浸泡1-2d促进种子萌发；NaOH和赤霉素溶液在浓度较低（分别为0.1-0.25mg/L和0.5%)时适当延长浸泡时间能促进萌发，浓度较高浸泡时间又较长对萌发无影响甚至抑制萌发，四种化学物质对种子萌发的影响与溶液的浓度及浸泡时间有关。     

刺轴含羞草———中国大陆新归化入侵植物

报道了1种中国大陆新记录归化入侵植物--刺轴含羞草Mimosa pigra L..标本采自海南省海口市南渡江河岸湿地.刺轴含羞草在世界热带地区已经泛滥成灾,极有可能在我国成为入侵植物而造成危害.提供了刺轴含羞草在中国大陆的分布信息,并进行了相关讨论.     

Soil phosphorus and water effects on growth,nutrient and carbohydrate concentrations, δ<Superscript>13</Superscript>C,and nodulation of mimosa (<Emphasis Type="Italic">Albizia julibrissin</Emphasis> Durz.) on a highly weathered soil

Growth and physiological performance of multipurpose tree species can be severely constrained by low phosphorus (P) availability in highly weathered soils. Limitations to plant growth are accentuated by seasonal dry periods. The overall objective of this study was to examine P fertilization and irrigation effects on survival, growth, biomass partitioning, foliar nutrients, intrinsic water-use efficiency (WUE) indexed by δ¹³C, Rhizobium nodulation, and carbohydrate content as an indicator of resprouting potential, of mimosa (Albizia julibrissin Durz.), a N₂-fixing tree species being tested for browse in agroforestry practices in south-central USA. In a field experiment carried out during two growing seasons near Booneville, Arkansas, USA, mimosa had a strong growth response to irrigation. The trial was arranged in a split plot design with three replications with irrigation as main plot treatment and P as sub-plot treatment. Mean total plant aboveground biomass at the end of the second growing season was 9.8 and 44.1 g plant⁻¹ for the rainfed treatment without and with 300 mm of irrigation water, respectively. Placed P fertilization increased mean total aboveground biomass from 19 g plant⁻¹ for the 0-P treatment to 69 g plant⁻¹ for the treatment with 90 kg P ha⁻¹ year⁻¹. Similarly, irrigation consistently increased stem basal diameter, total height, survival, root, stem, foliar and total aboveground biomass, and number of nodules per plant. Phosphorus fertilization increased basal diameter, and root and stem biomass in both irrigation treatments, survival and nodulation in the rainfed treatment, and foliar and total aboveground biomass in the rainfed +300 mm irrigation treatment. There was a decrease of foliar δ¹³C suggesting that WUE decreased with P fertilization. In a pot experiment, seedlings were subjected to a factorial combination of two irrigation treatments and six P levels in a randomized complete block design. Irrigation increased basal diameter, root, stem, foliar and total biomass, leaf area and nodulation, whereas P fertilization (i.e., levels from 0 to 3.68 g P kg⁻¹ soil) had similar effect in all the above variables except foliar biomass. Foliar P concentration to obtain 90% of the maximum total plant biomass (critical level) was estimated at 0.157%. Total nonstructural and water soluble carbohydrate, and starch concentrations increased non-linearly with irrigation and P addition suggesting impaired re-growth potential after defoliation of seedlings with reduced water supply and at low soil P availability. Results of this study indicated strong limitations for growth and regrowth potential of mimosa on a highly weathered soil with very low P availability and seasonal water content shortages. Placed (i.e., near the plant base) application of P appeared to be a good strategy to fertilize perennial woody plants.     

外来植物光荚含羞草的入侵研究

介绍了外来植物光荚含羞草(Mimosa bimucronata(DC.)Kuntze)的形态特征、分布范围、生态习性,分析了其入侵性,提出了该种的入侵警报,并给出了防治该种入侵的建议。     

不同类群植物叶片SPAD值的比较

利用SPAD-502型植物叶绿素计,测定了深圳福田、深圳海上田园、博罗罗浮山和广州大学城的85种植物叶片的SPAD值,通过对不同类群植物的比较,以期研究各类植物对环境的特殊适应性。结果表明,外来植物簕仔树的SPAD值远低于其他植物;裸子植物的PSAD平均值高于被子植物。除无瓣海桑外,大多数外来植物的SPAD值较低。大类群上,红树植物与内陆植物、双子叶和单子叶植物、不同地区同种植物、常绿与落叶、单叶与复叶、木本与草本、野生与栽培植物之间的差异性不显著。小类群比较时,如同科不同属或同属不同种植物之间就存在某些显著差异。     

两种含羞草科入侵植物的化感作用初探

以白菜、萝卜、莴苣为受体,以华南地区含羞草科入侵植物含羞草和金合欢的水浸液为供体,应用室内生物测定方法,研究供体植物对3种作物种子萌发与幼苗生长的影响.结果表明,含羞草和金合欢水浸液对白菜、萝卜和莴苣种子萌发和幼苗生长存在不同程度的抑制作用,且这种抑制作用随着浓度的增加而增强,当水浸液浓度为0.20g·mL-1时,各项指标均达到显著水平(P<0.05);比较两种供体植物对3种作物的综合化感效应指数,金合欢明显高于含羞草;对两种供体植物水浸液的定性鉴定显示,均含有酚类化感物质.     

含羞草叶片转录组测序及其黄酮合成途径解析

为了解析含羞草中黄酮类物质的生物合成途径，利用Illumina platform 2000^TM测序平台对含羞草叶片进行转录组测序，共获得94 182个Unigene，平均长度为695 bp，N₅₀值为1 159 bp。共有30 243个Unigene注释于50个GO功能组中，其中“代谢过程”“催化活性”以及“细胞”注释的Unigene数量较多。KEGG通路分析鉴定出49个Unigene注释在黄酮生物合成途径，分别编码查尔酮合成酶（CHS,12个Unigene）、查尔酮异构酶（CHI,4）、黄烷酮-3-羟化酶（F3H,3）、黄烷酮-3’-羟化酶（F3’H,9）、黄烷酮-3’,5’-羟化酶（F3’,5’H,1）、二氢黄酮醇4-还原酶（DFR,5）、黄酮醇合成酶（FLS,3）以及无色花色素还原酶（LAR,12）基因。从转录组数据库中鉴定出7 382个以单核苷酸和三核苷酸为主要类型的SSR标记。随机选出10对SSR引物进行扩增，其中有7对能够扩增出清晰的条带。