石菖蒲的克藻效应

 石菖蒲(Acorus tatarinowii)抑制藻类的机制除了对光和矿质营养的竞争外，主要是由于石菖蒲根系向水体分泌的化学物质，能伤害和清除藻类(克制作用，Allelopathic effect)；用培养石菖蒲的水培养藻类，可破坏藻类的叶绿素a，使其光合速率、细胞还原TTC的能力显著下降；在荧光显微镜下可看到藻细胞从鲜红色变为淡蓝色。     

Analysis of Acorus calamus chloroplast genome and its phylogenetic implications

Determining the phylogenetic relationships among the major lines of angiosperms is a long-standing problem, yet the uncertainty as to the phylogenetic affinity of these lines persists. While a number of studies have suggested that the ANITA (Amborella-Nymphaeales-Illiciales-Trimeniales-Aristolochiales) grade is basal within angiosperms, studies of complete chloroplast genome sequences also suggested an alternative tree, wherein the line leading to the grasses branches first among the angiosperms. To improve taxon sampling in the existing chloroplast genome data, we sequenced the chloroplast genome of the monocot Acorus calamus. We generated a concatenated alignment (89,436 positions for 15 taxa), encompassing almost all sequences usable for phylogeny reconstruction within spermatophytes. The data still contain support for both the ANITA-basal and grasses-basal hypotheses. Using simulations we can show that were the ANITA-basal hypothesis true, parsimony (and distance-based methods with many models) would be expected to fail to recover it. The self-evident explanation for this failure appears to be a long-branch attraction (LBA) between the clade of grasses and the out-group. However, this LBA cannot explain the discrepancies observed between tree topology recovered using the maximum likelihood (ML) method and the topologies recovered using the parsimony and distance-based methods when grasses are deleted. Furthermore, the fact that neither maximum parsimony nor distance methods consistently recover the ML tree, when according to the simulations they would be expected to, when the out-group (Pinus) is deleted, suggests that either the generating tree is not correct or the best symmetric model is misspecified (or both). We demonstrate that the tree recovered under ML is extremely sensitive to model specification and that the best symmetric model is misspecified. Hence, we remain agnostic regarding phylogenetic relationships among basal angiosperm lineages.     

石菖蒲的化学成分研究

运用色谱法从石菖蒲根茎提取物中分离得到18个化合物,经波谱学分析鉴定为:(7S,8R)-4,9’-di-hydroxyl-3,3’-dimethoxyl-7,8-dihydrobenzofuran-1’-propylneolignan(1),(7S,8R)-4,9’-dihydroxyl-3,3’-dimethoxyl-7,8-dihydrobenzofuran-1’-propylneoligan-9-O-β-D-glucopyranoside(2),7’-hydroxylariciresinol-9-acetate(3),5-羟基-3,7,4’-三甲氧基黄酮(4),野漆树苷(5),紫云英苷(6),松属素-3-O-芸香糖苷(7),山奈酚-3-O-芸香糖苷(8),德钦红景天苷(9),isoschaftoside(10),5-羟甲基糠醛(11),反式桂皮酸(12),3,7-dihydroxy-11,15,23-trioxo-lanost-8,16-dien-26-oicacid(13),3,7-dihydroxy-11,15,23-trioxo-lanost-8,16-dien-26-oic acid methyl ester(14),环阿屯醇(15),胡萝卜苷(16),羽扇豆醇(17),(22E,24R)-ergosta-5,7,22-trien-3β-ol(18)。除化合物4、11和16外,其余15个化合物均为首次从该植物中分离得到。     

Insecticidal and biological efficacy of two vegetable oils against Callosobruchus maculatus (Fabricius) (Coleoptera: Bruchidae) under laboratory conditions

Bioefficacy of two vegetable oils, namely ethyl oleate and Acorus calamus, were conducted against the pulse beetle Callosobruchus maculatus (Fabr.) under a constant temperature of 29 ± 1 °C and a relative humidity of 65 ± 5% R.H. Four concentrations (0.125, 0.25, 0.5 and 1.0%) of each oil were used against the adult and tested their latent effect on the immature stages of the beetle. The results obtained show insecticidal effect of both ethyl oleate and A. calamus oil; however, A. calamus oil proved to be more toxic to the adults at all the concentrations tested in comparison to the ethyl oleate oil. As the concentration of the oils decreased, the percentage mortality decreased. The obtained results concentrated on biological efficacy of the oils tested against the adults. Both oils affected the longevities of both male and female C. maculatus adults in comparison to the control. The oviposition periods of the adult female were affected significantly in comparison to the control. A. calamus oil prohibited oviposition completely at high concentrations of 0.5 and 1.0% and caused complete sterility to the females. Lower concentrations decreased the oviposition period greatly and reduced the number of eggs laid in comparison to the control. Ethyl oleate had an inconsiderable latent effect on the incubation period as well as the percentage of hatching of the resulting eggs. A. calamus oil decreased the percentage of egg hatchability with serious increase in the percent sterility. The two tested oils had slight extension in either larval or pupal stage of the resulting progeny of C. maculatus. Both oils show oviposition deterrency towards C. maculatus adults. The oviposition deterrent index was 100% when mung bean seeds were treated with A. calamus oil. The bruchid females laid all eggs on control seeds and no eggs were laid on treated seeds.     

石菖蒲及α-细辛醚对疲劳运动大鼠学习记忆的影响及其机制*

目的: 研究石菖蒲及其活性成分-α-细辛醚改善疲劳运动大鼠学习记忆的作用及其机制。方法: 80只SD大鼠随机分为正常对照组(A)、单纯运动组(B)、运动+α-细辛醚低、中、高剂量组(C、D、E)、运动+石菖蒲低、中、高剂量治疗组(F、G、H),每组10只。并在疲劳运动开始前2 h分别以0.10、0.50 和 1.00 mg α-细辛醚,灌胃C、D、E组,以0.12、1.20和4.80 g. kg^-1. wt^-1石菖蒲提取物,灌胃 F、G、H组。实验结束后采用水迷宫实验进行学习记忆检测,采用生化法检测SOD、NOS活性和MDA含量,免疫印迹法检测海马nNOS蛋白表达水平。结果: 实验后E和H组大鼠逃避潜伏期、海马脑组织MDA含量低于B、C、D、F和G组;穿越平台次数、海马脑组织SOD和NOS活性、nNOS蛋白表达高于B、C、D、F和G组,P均＜0.01。A、E、H组大鼠海马脑组织SOD活性依次为A＞E＞H组, 而MDA含量则相反,P均＜0.01;E组大海马脑组织NOS活性和nNOS蛋白表达低于A和H组,P＜0.01或P＜0.05,但A和H组,差异无显著性,P均＞0.05。A、E、H组大鼠逃避潜伏期和穿越平台次数,差异均无显著性,P均＞0.05。结论: 石菖蒲及α-细辛醚改善疲劳运动大鼠学习记忆的作用基本一致,其机制与纠正海马自由基代谢失衡和上调海马nNOS/NO信号有关。     

土壤逐渐干旱对菖蒲生长及光合荧光特性的影响

在土壤逐渐干旱过程中,连续测定典型湿地植物菖蒲生长发育状况及叶片叶绿素荧光参数,结果表明:短期内(实验第O-3天)土壤水分含量下降(土壤含水率自53.86％下降至42.6％)有利于菖蒲生长,干旱组菖蒲叶片Fv/ Fm、Yield、qP显著高于对照组(实验期间土壤平均含水率为53.49±0.6％)(P＜0.05),qN则低于对照组;随着土壤进一步干旱(土壤含水率自42.6％下降至18.02％,实验第3-9天),菖蒲叶片qN值则由0迅速上升至0.403,显著高于对照组(P＜0.05),Fv/Fm值与对照相比无显著差异(P＞0.05),叶片保持较高的热耗散以维持光合结构PSⅡ保持正常,并能以降低叶片含水率、叶面积(叶片卷曲避光)减少水分蒸腾及降低根系含水率促进水分吸收的方式进行自我保护;随着土壤干旱程度加剧(土壤含水率自18.02％下降至4.5％、实验第9-12天),菖蒲叶片Fv/ Fm、yield、qP值显著低于对照组(P＜0.05),qN值降为0,光合结构PSⅡ受到损坏,第11天、12天,叶片含水率分别降至75.79％和68.78％,此时菖蒲也逐步以自小叶片至大叶片的顺序枯萎衰亡,表明在土壤水分快速下降过程中过高的生物量将不利于菖蒲保持水分,而80％左右的叶片含水率是维持菖蒲存活的临界值.     

水体泥沙对菖蒲和石菖蒲生长发育的影响

三峡库区消落带植物恢复不仅面临长期淹水逆境,还面临高水位落差、反季节消落等环境因素的胁迫。菖蒲和石菖蒲是库区常见的两种湿生植物,探讨它们在泥沙水体中的生长发育,有利于为三峡库区消落带植被恢复的物种选择提供科学依据。用粒径小于100μm的泥沙分别配置浊度为30、60和90NTU的浑浊水体,8月将菖蒲(Acorus calamus L.)和石菖蒲(Acorus tatarinowii S.)植株分别种植于上述水体中,翌年4月统计植株的萌发数、叶长、叶宽、叶片数,利用水下饱和脉冲荧光仪(DIVING-PAM)测定叶片的快速光响应曲线。结果表明,各浊度组植株的萌发率与对照组相同,30NTU组石菖蒲和菖蒲的植株数显著多于对照组,且石菖蒲的植株数随水体浊度增加呈增多趋势,而菖蒲的植株数呈相反趋势。石菖蒲和菖蒲30NTU组植株的叶长、叶宽以及总叶片数、总叶长均显著大于对照组;石菖蒲60NTU组和90NTU组植株的叶长、叶宽和总叶长显著小于对照组(P<0.05),而菖蒲60NTU组的叶长、叶宽和叶片数显著大于对照组(P<0.01),90NTU组植株的叶长、叶宽和叶片数与对照组无显著差异(P>0.05),且菖蒲60NTU组和90NTU组植株的总叶片数和总叶长均显著低于对照组(P<0.01)。由快速光响应曲线可知,在较高光强照射下各浊度组植株的光化学荧光淬灭系数(qP)、非光化学淬灭系数(qN)和相对电子传递速率(rETR)均显著降低,但在低光下各浊度组植株的qP、qN和rETR均显著高于对照组,且菖蒲对低光的耐受范围大于石菖蒲。因而,菖蒲和石菖蒲均能长期生长于浅(0.9m)的悬浮泥沙水体中,具有一定的耐淹能力。     

关于亚马景天的名实问题

通过查阅亚马景天S.almae的等模式,发现该种应该是华北八宝Hylotelephium.tatarinowii的新异名。     

The population genetic diversity and pattern of Pteroceltis tatarinowii,a relic tree endemic to China,inferred from SSR markers

Pteroceltis tatarinowii (Cannabaceae), a relic tree endemic to China, is mainly distributed in limestone mountains and has a wide geographical range. In this study, 12 microsatellite primer pairs were assayed to analyse the genetic pattern and gene flow among 461 individuals sampled from 23 wild populations of P. tatarinowii. A high level of genetic diversity was detected based on high values of total alleles (159), the number of alleles (N_A = 6.373), expected heterozygosity (H_E = 0.696) and observed heterozygosity (H_O = 0.679). The high genetic diversity in this species may be attributed to its long‐life history, wide geographical distribution and wind dispersal. Only low genetic differentiation (G_ST = 0.137, F_ST = 0.138) was found among populations. Gene flow (migrants per generation, N_m) was estimated to be 1.56. This moderate level of gene flow possibly decrease interpopulation differentiation by buffering against genetic drift and improving gene exchange. However, spatial genetic structure was detected throughou the sampled range of the species (r = 0.311, p < 0.05) as well as in southern China (r = 0.453, p < 0.05), and may be related to terrain heterogeneity and the demographic history of P. tatarinowii. The east‐west high mountains of southern China might serve as physical barriers to seed and pollen flow. The isolation and local adaptation of different refugia may further limit gene flow. In addition, geographically remote populations might fail to effectively disperse pollen and seeds. Based on the above‐mentioned results, some suggestions for the conservation of the species are presented.