亏缺灌溉对板蓝根叶片光合生理特性及产量的影响

以北板蓝根(Isatis tinctoria)为研究对象, 于2018年在河西走廊中部干旱绿洲开展水分控制试验, 设轻、中、重度亏水及充分供水4个控水水平, 通过大田试验探究膜下滴灌条件下亏缺灌溉对板蓝根叶片生理指标、灌水量及产量的影响, 为河西地区板蓝根灌溉策略的制定提供理论依据。结果表明, 板蓝根叶片净光合速率(P_n)、蒸腾速率(T_r)和气孔导度(G_s)因营养和肉质根生长期受到亏缺灌溉影响而显著下降, 降幅随亏水程度的加剧而增大, 轻度亏水处理对叶片光合能力的影响不显著, 且在复水之后存在一定的补偿响应; 轻度亏水处理的产量与对照(8 348.91 kg·hm^-2)相比无显著差异, 而其它处理的产量均有不同程度的下降; 灌水量与产量的拟合关系呈二次抛物线, 即产量不随灌水量的增加而升高。因此, 综合分析表明膜下滴灌调亏降低了板蓝根叶片的光合能力, 而营养生长期轻度亏缺灌溉可以节水并提高产量和灌溉效率。     

Effects of Deficit Irrigation on the Photosynthetic and Physiological Characteristics of Leaves and Yield of Isatis tinctoria

以北板蓝根(Isatis tinctoria)为研究对象, 于2018年在河西走廊中部干旱绿洲开展水分控制试验, 设轻、中、重度亏水及充分供水4个控水水平, 通过大田试验探究膜下滴灌条件下亏缺灌溉对板蓝根叶片生理指标、灌水量及产量的影响, 为河西地区板蓝根灌溉策略的制定提供理论依据。结果表明, 板蓝根叶片净光合速率(P_n)、蒸腾速率(T_r)和气孔导度(G_s)因营养和肉质根生长期受到亏缺灌溉影响而显著下降, 降幅随亏水程度的加剧而增大, 轻度亏水处理对叶片光合能力的影响不显著, 且在复水之后存在一定的补偿响应; 轻度亏水处理的产量与对照(8 348.91 kg·hm^-2)相比无显著差异, 而其它处理的产量均有不同程度的下降; 灌水量与产量的拟合关系呈二次抛物线, 即产量不随灌水量的增加而升高。因此, 综合分析表明膜下滴灌调亏降低了板蓝根叶片的光合能力, 而营养生长期轻度亏缺灌溉可以节水并提高产量和灌溉效率。     

多基因联合分析棒束孢属Isaria（Ascomycota,Cordycipitaceae）系统发育关系

对棒束孢属Isaria及近缘属物种开展5基因（nrSSU、nrLSU、tef-1α、rpb1和 rpb2）测序并联合分析,结合GenBank相关类群序列,探讨棒束孢属系统发育关系,最终获得95个菌株、58个明确分类群的2-5基因序列。利用MEGA和MrBayes软件进行多基因聚类分析,结果表明棒束孢属多系起源于虫草菌科中,分3个不同分支。A支主要由Isaria cicadae、I. teniupes、I. coleopterorum、I. fumosorosea和I. cateniannulata等组成;B支包括I. poprawkii、I. locustica、I. javanica、I. amoenerosea和I. cateniobliqua;C支仅有I. farinosa。分支间被Cordyceps militaris、C. ninchukispora、C. pruinosa等隔开。棒束孢在形态上,主要以瓶梗基部膨大、尖端变细及孢子呈链状等特征与其他类群分开,但同时也发现有棒状分生孢子梗和单孢子类型。基于节点的分歧时间预测分析,推测棒束孢属首次分化于70Mya,但棒束孢属主要物种形成却在60-55Mya,且3个分支的棒束孢物种为快速同时形成,而后大多数类群表现遗传稳定。同时发现,与Isaria Clade A较近一支有粉被玛利亚霉Mariannaea pruinosa（C. pruinosa无性型）和蛹草蚧霉Lecanicillium militaris（C. militaris无性型）;与粉棒束孢距离最近一支有Akanthomyces aculeatus（C. tuberculata无性型）和L. attenuatum（C. confragosa无性型）,是两个不同的属征分类群,且相互间遗传距离较近。根据棒束孢属及其近缘种属形态特征的复杂性推测,棒束孢属在快速物种形成中,其近缘类群存在一定程度的丢失和选择性演化。     

Immunomodulatory effects of arabinogalactan-proteins from Baptisia and Echinacea

The influences of different arabinogalactan-proteins (AGPs) on proliferation and IgM-production of mouse lymphocytes as well as nitrite- and IL6-production of mouse macrophages were investigated in vitro. AGPs have been isolated and purified from roots of Baptisia tinctoria and Echinacea pallida and suspension culture of Echinacea purpurea. Comparing the AGPs, there are differences with regard to fine structure as well as to activities. AGPs from roots of B. tinctoria and E. pallida show high activity in all test systems. AGP from cell culture of E. purpurea shows no influence on proliferation of mouse lymphocytes, only weak influence on the IgM-production of mouse lymphocytes and weak stimulation of nitrite- and IL6-production in alveolar mouse macrophage culture.     

马兰的学名考证

马蔺是鸢尾科鸢尾属的植物,在我国北方甚常见,它的学名比较混乱,不同的作者引用的学名差异甚大。因此本文作一粗略考证,试图澄清,但因水平所限,讹误之处,敬请批评指正。     

Low-conductance chloride channel activated by cAMP in the epithelial cell line T84

We have studied the modulation and pharmacological properties of two anion channels in T₈₄ cells by recording single channel and transepithelial currents. One channel had an outwardly rectifying current-voltage I/V curve, was rarely active in cell-attached patches, and was unaffected by cAMP. The other channel had lower conductance (8.7 pS at 37°C) and a more ohmic I/V relationship. Exposure to cAMP increased the probability of observing low-conductance channel activity in cell-attached patches> 6-fold. Extracellular DIDS (4,4'-diisothiocyanatostilbene-2,2'-disulfonic acid) or IAA-94 (an indanyloxyacetic acid) inhibited the outward rectifier but did not affect the low-conductance channel or cAMP-stimulated transepithelial current. These results suggest the low-conductance Cl channel may contribute to apical membrane conductance during cAMP-stimulated secretion.     

白囊耙齿菌产锰过氧化物酶条件优化及其对染料的脱色

锰过氧化物酶（manganese peroxidase,MnP）是白腐真菌降解多种异生物质的主要降解酶之一。本研究对白囊耙齿菌Irpex lacteus产MnP的酶活曲线进行监测,利用单因素和正交试验对I. lacteus产MnP的发酵条件进行优化,同时检测了I. lacteus的MnP粗酶液对5种染料的脱色效果。结果显示,I. lacteus在培养5d时MnP活性较大;I. lacteus产MnP较优的条件为：可溶性淀粉20g/L、尿素1g/L、pH 6.3、CaCl₂ 1mmol/L、FeCl₃ 1mmol/L,该条件下MnP活性达29.24U/L,与优化前MnP活性相比提高了1.25倍;I. lacteus的MnP粗酶液对5种染料均可脱色,其中对直接大红和活性红的脱色效果更为明显,脱色5d后的脱色率分别达到82%和81%。     

入侵植物五爪金龙根系深色有隔内生真菌的侵染特征

深色有隔内生真菌（DSE）广泛侵染华南地区外来入侵植物五爪金龙。显微观察发现五爪金龙根系具有大量的泡囊,其最显著的特征是大量脂质的富集和被分解成小脂质体,并通过透明或深色菌丝转移,说明了五爪金龙和DSE之间进行碳转移。富含脂质的泡囊可产生透明菌丝和自我复制,说明泡囊具有繁殖功能。富含脂质的泡囊和透明菌丝等非典型结构没有可分辨的或具透明的细胞壁,是活跃的真菌结构。透明菌丝和富含脂质的泡囊主要定殖在生理活性强的根组织中。深色有隔菌丝和微菌核是DSE的典型结构,主要定殖在相对不活跃的根组织中。DSE定殖于五爪金龙根的维管柱、皮层、表皮细胞和表面,同时延伸到土壤,在宿主植物和土壤之间形成连续的系统的真菌网络。根据DSE的多态性质、庞大的真菌网络和脂质的富集及其分布,探讨了DSE和入侵植物五爪金龙潜在的互惠共生关系。     

Flavonoid similarities among five species of Isocoma

The flavonoid profiles of the leaf resins from Isocoma veneta, I. tenuisecta, I. acradenia, I. drummondii, and I. eremophila were identified by TLC co-chromatography with authentic samples. Thirty flavonoid aglycones were identified, most of which are methylated, based on apigenin, luteolin, kaempferol, quercetin, scutellarein (I. veneta)only, and 6-OH-kaempferol (I. tenuisectaonly). Cluster analyses were performed using Jaccard similarities of both presence/absence data and of biosynthetic step indices. The latter method yielded consistently higher similarity coefficients and is believed to be a truer indication of the chemical similarities among Isocoma species.     

Genetic diversity and population structure of endangered Isoetes coreana in South Korea based on RAPD analysis

Isoetes coreana Chung and Choi is on the list of critically endangered species in South Korea. Using randomly amplified polymorphic DNA (RAPD) markers, we investigated the genetic diversity within and between seven local populations of I. coreana. Ten RAPD primers produced a total of 94 bands, of which 59 (62.8%) were polymorphic. A low level of genetic diversity was recognized within the populations of I. coreana: polymorphic loci (P), with values ranging from 3.4% to 33.9%, and a mean value of 15.5% being observed. Analysis of molecular variance (AMOVA) showed that genetic diversity was greater among populations (81.6%) than within populations (19.7%) or among the three regions included in this study (Han River, Youngsan River, and Nakdong River). In addition, a high degree of genetic differentiation (θ^B = 0.742) was detected among the populations. These results indicate that genetic differentiation has occurred very rapidly. However, the rate of gene flow between populations was found to be as low as 0.059, irrespective of the genetic and geographical distances between the populations, which indicates that genetic drift must have played an important role in forming the present populations of I. coreana. Because a reduction of genetic diversity as a result of genetic drift is undesirable, increasing the gene flow between populations of Korean quillwort I. coreana should be considered as a conservation strategy.     

Phenotypic and genomic characteristics of rhizobia isolated from Genista tinctoria root nodules

Forty three rhizobial strains isolated from root nodules of Genista tinctoria growing in England, Ukraine, and Poland were compared with 21 representatives of the recognized rhizobial species and two unclassified Bradyrhizobium sp. (Lupinus) strains by performing a numerical analysis of 102 phenotypic features and with the reference bradyrhizobia by simplified AFLP analysis with one restriction enzyme PstI and one selective primer PstI-A. All Genista tinctoria microsymbionts were slow-growing bradyrhizobia with generation time of 10–14 h, acid tolerant, salt sensitive, and antibiotic resistant. Cluster analysis based on the phenotypic properties of all bacteria included, grouped dyer's broom rhizobia together with Bradyrhizobium strains, and classified them into three major phena according to their geographic origin. Genista tinctoria nodule isolates were separated into three clusters with the strain composition as in a phenogrouping by AFLP patterns. The presented results, suggest the relationship of G. tincoria microsymbionts to Bradyrhizobium species and show the usefulness of AFLP analysis for differentiation and classification of the studied rhizobia.     

Identification of a cDNA encoding a novel C18-Δ polyunsaturated fatty acid-specific elongating activity from the docosahexaenoic acid (DHA)-producing microalga, Isochrysis galbana

Isochrysis galbana, a marine prymnesiophyte microalga, is rich in long chain polyunsaturated fatty acids such as docosahexaenoic acid (C22:6n-3, Δ^{4,7,10,13,16,19}). We used a polymerase chain reaction-based strategy to isolate a cDNA, designated IgASE1, encoding a polyunsaturated fatty acid-elongating activity from I. galbana. The coding region of 263 amino acids predicts a protein of 30 kDa that shares only limited homology to animal and fungal proteins with elongating activity. Functional analysis of IgASE1, by expression in Saccharomyces cerevisiae, was used to determine its activity and substrate specificity. Transformed yeast cells specifically elongated the C18-Δ⁹ polyunsaturated fatty acids, linoleic acid (C18:2n-6, Δ^9,12) and -linolenic acid (C18:3n-3, Δ^9,12,15), to eicosadienoic acid (C20:2n-6, Δ^11,14) and eicosatrienoic acid (C20:3n-3, Δ^11,14,17), respectively. To our knowledge this is the first time such an elongating activity has been functionally characterised. The results also suggest that a major route for eicosapentaenoic acid (C20:5n-3, Δ^5,8,11,14,17) and docosahexaenoic acid syntheses in I. galbana may involve a Δ⁸ desaturation pathway.     

基于多组织稳定同位素比值的热带大西洋4种鲨鱼营养生态位分化

不同代谢速率组织间的碳、氮稳定同位素比值(δ¹³C和δ¹⁵N)可以反映生物不同时间尺度的摄食信息,对探讨物种间摄食、栖息地利用和营养生态位的变化具有重要的指示作用。本研究以在大西洋热带海域兼捕的大青鲨、长鳍鲭鲨、拟锥齿鲨和尖吻鲭鲨为对象,通过测定其肌肉、肝脏和血液的δ¹³C和δ¹⁵N值,探讨4种鲨鱼营养生态位分化。结果表明: 与长鳍鲭鲨相比,尖吻鲭鲨、拟锥齿鲨和大青鲨的δ¹⁵N值相似且相对较高;大青鲨与其他鲨鱼存在摄食隔离,表现出独特的营养生态位;尖吻鲭鲨营养生态位宽幅最大,摄食食物种类和(或)栖息环境类型更多样化,其与拟锥齿鲨的营养生态位重叠度最高,说明两种鲨鱼具有潜在的资源竞争关系。尖吻鲭鲨、拟锥齿鲨和大青鲨组织间的δ¹³C、δ¹⁵N差值与其叉长均无显著相关关系,说明3种鲨鱼近期内无明显摄食变化;而长鳍鲭鲨的肝脏、血液和肌肉组织的δ¹⁵N差值与叉长显著相关,说明长鳍鲭鲨在短期内存在摄食变化。肝脏和血液的δ¹³C、δ¹⁵N值的相似性反映了两种组织整合摄食时间周期相近,其较高的代谢速率可以反映相对短时间周期的摄食信息。     

Effects of glyphosate on interspecific competition between Solidago canadensis and Imperata cylindrica

Aims The extensive use of herbicide to control invasive plants would change the relationship between alien and neighboring plants. In order to provide data for rational use of herbicide and a theoretical reference for further studies on the ecological effects of glyphosate, we explored the variation of the relationship between an invasive plant Solidago canadensis and a native plant Imperata cylindrica when they were sprayed glyphosate.
Methods A replacement series experiment was conducted from June to August 2016 in Wetland Ecosystem Research Station of Hangzhou Bay, State Forestry Administration, to examine the effects of glyphosate at seven concentration levels (0, 0.3, 0.6, 0.9, 1.2, 1.5, 1.8 mL·L^-1) on the growth and interspecific competition of S. canadensis and I. cylindrica.
Important findings (1) Glyphosate treatment significantly inhibited the growth of S. canadensis and I. cylindrica (p < 0.05). During the test, cumulative growth of height and leaf number of S. canadensis were apparently reduced with the increase of glyphosate concentration, but the leaf number of S. canadensis treated with 0.3- 1.5 mL·L^-1 glyphosate was re-growing with time, while the one treated with 1.8 mL·L^-1 was mostly dead. The withering rate of tiller and green leaf of I. cylindrica also significantly increased with the increase of glyphosate concentration, and the growth indices of this plant treated with 0.3-0.6 mL·L^-1 were also re-growing with time. (2) Glyphosate treatment significantly affected interspecific competition (p < 0.05), which diminished as the glyphosate concentration increased. (3) Interspecific competition has significant influence on the biomass allocation of S. canadensis (p < 0.05). When facing competition, S. canadensis would allocate more organic matter to root and thus increase the ratio of root to shoot. Competition only inhibited the tiller number and total biomass of I. cylindrica, but insignificantly affected its ratio of root to shoot. (4) The interaction between glyphosate treatment and S. canadensis-I. cylindrica interspecific relationship also significantly influenced the biomass of S. canadensis and I. cylindrica (p < 0.05), but insignificantly affected the root/shoot ratio of two plants. Different plants have different tolerance to glyphosate stress. Compared with native plant I. cylindrica, S. canadensis has stronger tolerance to glyphosate. Low-concentration glyphosate could decrease the competitive intensity between S. canadensis and I. cylindrica, which may disturb the structure and dynamics of plant communities.     

The anthocyanidins of some new guinea impatiens

17 strains of New Guinea Impatiens belonging to the I. schlecteri—linearifolia group and to the I. hawkeri—mooreana—nivea group were analysed for the anthocyanidin pigments. Pelargonidin predominated in the schlecteri group white malvidin was most common in the mooreana group.     

中国马兜铃属和关木通属(马兜铃科)概览

马兜铃属(广义) (Aristolochia sensu lato)具有花单被、花萼管状、合蕊柱、子房下位、中轴胎座、胚珠多数、蒴果等主要特征, 广布于全世界的热带、亚热带和温带地区, 约有600种, 是马兜铃科中种类最多的属。依据Flora of China, 我国有本属植物45种, 其中33种为中国特有。近些年, 国内大量的新类群被相继报道, 特别是云南、广西两地, 而另一些类群则得到了确认、恢复、重新发表或修订。最近, 基于形态和分子证据, 关木通属(Isotrema)因其花萼管急剧弯曲; 合蕊柱3裂; 雄蕊6, 成对与合蕊柱裂片对生; 蒴果由上而下开裂等区别特征而从广义马兜铃属中被分出独立成属。本文基于大量的野外调查、标本鉴定、数码照片考证和相关文献的仔细研究, 重新梳理了中国马兜铃属和关木通属的种类及分布情况, 确认现阶段中国马兜铃属17种和关木通属58种1亚种, 并一一记述同时编制了最新的检索表。其中, 柔叶关木通(I. mollis)、线叶关木通(I. neolongifolia)的种级地位得到重新确认, 并提供了图版。探讨了优贵马兜铃(A. gentilis)、川滇马兜铃(A. chuandianensis)和纤细马兜铃(A. gracillima)的关系, 昆明关木通(I. kunmingense)与波氏关木通(A. bonatii)的关系, 以及卵叶关木通(I. ovatifolium)、葫芦叶关木通(I. cucurbitoides)、西藏关木通(I. griffithii)、过石珠(I. versicolor)、大别山关木通(I. dabieshanensis)等复合群和袋形关木通(I. saccata)等物种存在的问题。     

Transpiration rates of the understory annual Impatiens capensis (Balsaminaceae) in response to the autumnal changes in canopy leaf area

Leaf transpiration rates of Impatiens capensis were measured beneath a broadleaved deciduous forest canopy over successive growing seasons using a steady-state porometer. The transpiration measurements, which continued into early autumn, provided a framework for assessing whether I. capensis exhibits stomatal opening in response to the autumnal increase in available direct-beam radiation reaching the forest floor. The deciduous canopy LAI (leaf area index) decreased from a growing season maximum of 3.94 m² m⁻², while the understory I. capensis population located along a stream channel maintained LAI values ranging from 0.58 to 1.05 m² m⁻² late into the growing season. Late morning and early afternoon leaf transpiration rates during the months of June and July averaged about 8 μg cm⁻² s⁻¹, with a mean stomatal conductance of 0.5 cm s⁻¹. In August, leaf transpiration averaged almost 12 μg cm⁻² s⁻¹, with stomatal conductance exceeding 1.5 cm s⁻¹. However, beginning in early to mid-September, before canopy leaf-fall, the persistent green leaves of I. capensis exhibited a sharp decline in transpiration, possibly a result of decreasing vapor pressure deficits or non-lethal physiological damage induced by cold stress. This physiological decline offsets any advantage that could have been gained by the increased exposure to direct-beam radiation after canopy leaf-fall in mid-October. Although green leaf area and seed-bearing capsules may persist until the first frost in October or early November, there is no evidence of stomatal opening suggestive of carbon assimilation for enhanced seed development during this early autumn period. We conclude that the persistent green leaf area of I. capensis fails to exploit the increase in available direct-beam radiation in the final stage of its life cycle.     

花群珊瑚对两种微藻的摄食

以花群珊瑚为材料,采用碳清除率测定、PCR分子营养标记和组织学观察的方法,研究花群珊瑚是否摄食亚心形扁藻和球等鞭金藻。结果表明: 花群珊瑚对球等鞭金藻的碳清除率显著高于亚心形扁藻,分别为0.44和0.11 pg·mL^-1·polyp^-1·h^-1。球等鞭金藻烯酰基载体蛋白还原酶基因片段作为分子标记在投喂组珊瑚组织中可扩增出目的片段。亚心形扁藻18S rRNA基因的引物在相应投喂组珊瑚组织中也可扩增出目的片段。组织学观察发现: 投喂组珊瑚水螅体内部隔膜较宽,隔膜与体壁的胃层都存在大量食物泡。亚心形扁藻投喂组在体壁胃层的食物泡中和口道沟处均发现未消化完全的亚心形扁藻。球等鞭金藻投喂组则在隔膜胃层和体壁胃层内的食物泡中发现所摄食金藻。因此,碳清除率、分子营养标记以及组织学观察均表明花群珊瑚对亚心形扁藻与球等鞭金藻存在摄食现象。     

中国丝盖伞属裂盖组的三个新种

丝盖伞属裂盖组Inocybe sect. Rimosae sensu lato是一个分类难度较大的类群,组内的一些种类被认为是复合种。分子系统发育分析表明该组并非单系群,该组成员隶属于丝盖伞科下的2个属级分支,Inosperma分支和Pseudosperma分支。本文结合形态学特征和分子序列分析,对我国丝盖伞属裂盖组进行了分类学研究,发现3个新种：长白丝盖伞Inocybe changbaiensis、新茶褐丝盖伞I. neoumbrinella和云南丝盖伞I. yunnanensis。长白丝盖伞和新茶褐丝盖伞产自中国东北,前者生于针阔混交林下,后者生于柳树林下;云南丝盖伞产自云南省昆明市,生于阔叶树下。基于LSU序列的系统发育分析结果显示,长白丝盖伞隶属于Inosperma分支,新茶褐丝盖伞和云南丝盖伞隶属于Pseudosperma分支。本文对此进行了形态描述和特征图示,并讨论了新种与近缘种之间的异同。编制了中国丝盖伞属裂盖组已知种类的分种检索表。