Flavonoids and the chemotaxonomy of three Sophora species

Sophora microphylla, S. prostrata and S. tetraptera are distinguishable from one another by their leaf flavonoids. S. microphylla is distinguished by the present of rhamnosylvitexin and rhamnosylisovitexin and S. tetraptera by the presence of apigenin-7-O-rhamnosylglucoside-4′-O-glucoside and the 7-O-glucosides of apigenin, 7,4′-dihydroxyflavone, luteolin and 7,3′,4′-trihydroxyflavone. Sophora prostrata lacks all these flavonoids, but has several pigments which are common to all three species.     

伊犁河谷苦豆子C、N、P含量变化及化学计量特征

研究苦豆子不同器官中碳、氮、磷元素的化学计量特征的季节变化有助于深入了解该植物蔓延的生态学机制。系统分析了伊犁河谷苦豆子根、茎、叶的碳(C)、氮(N)、磷(P)化学计量特征及其季节动态变化。结果表明∶苦豆子C、N、P含量均值分别为391.40、13.17、1.51mg/g,C∶N、N∶P、C∶P均值分别为45.61、8.52、326.38。苦豆子根、茎、叶在整个生长季内C、N、P均值含量变化一致,为叶茎根。在生态化学计量特征的分析中规律则不同,C含量随着生长时期的增加而增加,N和P的含量则随着生长时期的增加而减少;苦豆子根系中的C、N、P含量有随着深度变化而递减的趋势;器官间的差异性说明植物在不同生长时期,各器官对C、N、P的吸收利用具有特异性。植物叶片中C、N、P含量和N∶P普遍较低,苦豆子生长受N、P的共同限制,更容易受到N元素的限制。     

A comparative electrophoretic study of the seed albumins fromSophora microphylla andPisum sativum (Leguminosae)

The albumin proteins from seed ofSophora microphylla Ait. and from cotyledons ofPisum sativum L. (cv. Greenfeast) have been analysed electrophoretically using a range of gels of varied pore size. Plots of mobility [as 100 log₁₀ (R _f × 100)] vs.acrylamide content of gel indicate that very few of the albumins fromS. microphylla are homologous with albumins fromP. sativum. Despite the diverse compositions of the two fractions, their amino acid analyses were surprisingly similar.     

Phytochemicals Content,Antioxidant and Antibacterial Activities of Sophora viciifolia

The objective of this study is to compare the efficacy of ethanol extracts from different parts of Sophora viciifolia. The content of polyphenols, flavonoids, alkaloids, and antioxidant capacity, antimicrobial activity were investigated, and individual polyphenols and alkaloids were analyzed and quantified by ultra‐high performance liquid chromatography (UPLC). The microdilution method was used to determine the antimicrobial activity of extracts from S. viciifolia on six strains. The results for extracts from the different parts (flowers, leaves, and fruit) were compared in varying concentrations to determine whether one extract source is superior to another. Testing verified that extracts from the different parts of S. viciifolia did vary, as expected. For example, extract from the leaves had the best antimicrobial activity against pathogenic Candida albicans, but all extracts had good antimicrobial activity against the six tested strains. These results reveal that the active substances in S. viciifolia are abundant and have good antioxidant and antimicrobial activities, which can provide theoretical support for the subsequent development and utilization of S. viciifolia extracts.     

Effects of grazing on photosynthetic characteristics of major steppe species in the Xilin River Basin,Inner Mongolia,China

Species composition and photosynthetic characteristics of dominant species of ungrazed plot (UG), overgrazed plot (OG), and restored grazed plot (RG) were determined in the Xilin River Basin, Inner Mongolia, China. Both heavily grazing and restoration significantly affected the composition of different species and life forms. Leymus chinensis, Stipa grandis, and Cleistogenes polyphylla, three dominant perennial grasses in UG plot, contributed 58.9 % aboveground biomass to that of whole community, and showed higher net photosynthetic rate (P _N), transpiration rate (E), and intrinsic water-use efficiency (WUE). In OG plot, relative biomass of L. chinensis and S. grandis significantly decreased, while relative biomass of three shrubs/sub-shrubs, Caragana microphylla, Artemisia frigida, and Kochia prostrata, obviously increased. Heavy grazing significantly decreased P _N, E, and WUE of L. chinensis and S. grandis, while shrubs/sub-shrubs showed significantly higher photosynthetic activity and WUE than the grasses. After 18-year restoration, photosynthetic activities of L. chinensis and S. grandis were significantly higher than those in the OG plot. The proportion of L. chinensis, S. grandis, and C. microphylla significantly increased, and relative biomass of C. polyphylla, A. frigida, and K. prostrata markedly declined in RG plot. We found close relationships between physiological properties of species and their competitive advantage in different land use types. Higher photosynthetic capability means more contribution to total biomass. The variations in physiological characteristics of plants could partly explain the changes in species composition during degrading and restoring processes of Inner Mongolia typical steppes.     

小叶锦鸡儿天然居群叶形态性状变异研究

为揭示小叶锦鸡儿(Caragana microphylla)天然居群叶形态性状的变异规律及其生态适应性特征,该研究以10个小叶锦鸡儿天然居群为对象,通过多重比较、巢式方差分析、相关性分析、聚类分析和主成分分析等方法,对7个叶形态性状进行分析。结果表明：(1)小叶锦鸡儿叶形态性状在居群内和居群间均存在极显著差异(P < 0.01),平均变异系数为10.13%,不同性状的变异幅度为6.23%~12.78%;平均叶形态性状的表型分化系数为43.62%,居群内变异(30.09%)大于居群间变异(24.91%),说明居群内是其叶形态性状变异的主要来源。(2)相关性分析表明,环境因子对小叶锦鸡儿的叶形态性状变异有很大的影响,在地理空间上主要呈现出沿海拔梯度的变异模式;主成分分析的结果显示,小叶宽、叶柄宽和叶柄长对小叶锦鸡儿叶形态变异起主导作用;利用欧式距离对小叶锦鸡儿居群进行UPGMA聚类分析结果显示,基于叶形态性状和环境因子可分别将小叶锦鸡儿10个居群分为3类和2类,Mantel检验结果表明,小叶锦鸡儿的叶形态性状变异不存在地理连续性。研究结果为小叶锦鸡儿的适应性进化和开发利用提供了理论依据。     

不同径级国槐行道树重金属富集效能比较

采用ICP-OES测定北京市台基厂大街行道树国槐各器官中7种重金属(Cd、Cr、Ni、Cu、Mn、Pb、Zn)含量,比较不同径级国槐重金属富集效能。结果表明:国槐中重金属含量因胸径级、器官、元素种类不同而存在差异。各径级国槐重金属含量大小总体趋势为ZnMnCuPbCrNiCd,各器官中树皮和根对重金属的吸收能力最强,其次是叶和枝,树干对重金属的吸收能力最弱。不同径级国槐对重金属的富集能力存在差异,表现为小径级中径级大径级。国槐各器官中重金属积累量大小顺序为根干枝叶,重金属积累量随着胸径级扩大和生物量的增加而增加。综合比较不同径级国槐重金属年均积累量、单位面积富集量和单位空间富集量,小径级(20≤DBH30 cm)国槐富集效能最高。     

A Tolerance Gene for Prenylated Flavonoid Encodes a 26S Proteasome Regulatory Subunit in Sophora flavescens

Yeast functional screening with a Sophora flavescens cDNA library was performed to identify the genes involved in the tolerant mechanism to the self-producing prenylated flavonoid sophoraflavanone G (SFG). One cDNA, which conferred SFG tolerance, encoded a regulatory particle triple-A ATPase 2 (SfRPT2), a member of the 26S proteasome subunit. The yeast transformant of SfRPT2 showed reduced SFG accumulation in the cells.     

Distribution of alkanes and fatty acids in theCondalia montana (Rhamnaceae) species complex

The alkane and fatty acid composition of the lipid extracts from leaves of 14 populations ofCondalia: C. microphylla f.xanthocarpa, C. microphylla f.erythrocarpa, C. microphylla f.melanocarpa, C. montana, andC. buxifolia, were determined by gas chromatography. Seventeen alkanes and 14 fatty acids were investigated and a predominance of nonacosane, hentriacontane, palmitic and linoleic acids in all species was found.     

Tight control of nitrate acquisition in a plant species that evolved in an extremely phosphorus‐impoverished environment

Hakea prostrata (Proteaceae) has evolved in an extremely phosphorus (P)‐limited environment. This species exhibits an exceptionally low ribosomal RNA (rRNA) and low protein and nitrogen (N) concentration in its leaves. Little is known about the N requirement of this species and its link to P metabolism, despite this being the key to understanding how it functions with a minimal P budget. H. prostrata plants were grown with various N supplies. Metabolite and elemental analyses were performed to determine its N requirement. H. prostrata maintained its organ N content and concentration at a set point, independent of a 25‐fold difference nitrate supplies. This is in sharp contrast to plants that are typically studied, which take up and store excess nitrate. Plants grown without nitrate had lower leaf chlorophyll and carotenoid concentrations, indicating N deficiency. However, H. prostrata plants at low or high nitrate availability had the same photosynthetic pigment levels and hence were not physiologically compromised by the treatments. The tight control of nitrate acquisition in H. prostrata retains protein at a very low level, which results in a low demand for rRNA and P. We surmise that the constrained nitrate acquisition is an adaptation to severely P‐impoverished soils.     

Competition between Salicornia europaea and Atriplex prostrata (Chenopodiaceae) along an experimental salinity gradient

Salicornia europaea L. is a halophyte that often occupies the lowestand most saline (>3.5% total salt) areas of salt marshes. Atriplexprostrata Boucher is less salt tolerant than S. europaea and oftengrows in a less saline (<2.0% total salts) zone adjacent to S. europaea. The purpose of this experiment was to determine thecompetitive outcome when these two species are grown at differentsalinities to ascertain the extent salinity and competition affect plantzonation. Plants were grown in a de Wit replacement series at 85, 170,and 340 mM NaCl in half-strength Hoagland's no. 2 nutrient solution fortwo months. There was a significant effect of salt concentration,competition, and their interaction on biomass production of S. europaea plants. However, only salt concentration significantly affectedbiomass production of A. prostrata plants. Results of thisexperiment confirmed the results of other studies that demonstrated thatthe more salt tolerant species were less competitive at lower salinities. Atriplex prostrata was the better competitor at 85 mM NaCl, whereasS. europaea was the better competitor at 340 mM NaClbecause growth of A. prostrata was inhibited. At 170 mMNaCl, A. prostrata biomass production decreased more than S. europaea biomass in mixed culture.     

Do birch-feeding caterpillars make the right feeding choices?

Summary The effects of leaf quality on caterpillar performance are frequently investigated, as are the feeding preferences of caterpillars, but rarely are the two considered together to see how preferences match performance. I looked at the preferences and performance of the specialist feeder Achlya flavicornis and the generalist Spilosoma luteum on Betula pendula leaves which were artificially damaged, mined or left undamaged, and on leaves of different ages. Often feeding preferences were not for the leaf types that gave faster development, larger pupae or greater survival. A. flavicornis preferred medium aged to older leaves though medium aged leaves produced smaller pupae. They did not discriminate between young and medium aged leaves, though larvae fed young leaves developed more slowly, and had lower survival and lower adult emergence. S. luteum larvae did not discriminate between damaged and undamaged leaves, though feeding on damaged leaves gave smaller pupae and lower adult emergence. I suggest that generalists like S. luteum might be unable to make feeding choices between leaves that are on the same tree and vary only slightly because populations are exposed to much greater variation across the wide range of potential food plants individuals may encounter. Possible differences in within-plant feeding selectivity between generalists and specialists should be investigated. A. flavicornis is a leaftier for which selection of a suitable leaf for tying could be more important in the first instance than feeding considerations. Larvae preferred younger to older leaves for tying, and larvae tended to feed on the tied leaves, so tying preferences explain the initial feeding preferences.     

氮沉降和降雨变化对荒漠草原凋落物分解的影响

以荒漠草原凋落物为研究对象,通过设置自然降雨(CK)、增雨30%(W)和减雨30%(R) 3种水分处理和0 (N0)、30(N30)、50 (N50)和100 kg hm~(-2) a~(-1)(N100)4种氮素(NH_4NO_3)水平处理,用分解袋法,研究内蒙古短花针茅荒漠草原短花针茅(Stipa breviflora)、冷蒿(Artemisia frigida)、无芒隐子草(Cleistogenes songorica)和木地肤(Kochia prostrata)凋落物分解过程,旨在阐明荒漠草原凋落物分解过程及其对氮沉降和降雨变化的响应特征,为荒漠草原生态系统物质循环过程响应气候变化研究提供基础数据。结果表明:1)经过270 d分解后,短花针茅、冷蒿、木地肤和无芒隐子草干物质残留率分别为69.95%—78.67%、68.89%—79.89%、64.68%—79.23%、66.89%—79.38%,分解速率为木地肤无芒隐子草冷蒿短花针茅。2)氮沉降和降雨对短花针茅和冷蒿凋落物分解速率产生显著影响(P0.05),其交互作用对这两种凋落物分解速率不显著(P0.05)。氮沉降和降雨以及交互作用均对无芒隐子草和木地肤凋落物分解速率产生显著影响(P0.05)。3)单一水分或氮素的添加均提高土壤微生物量碳氮含量,而水氮交互作用下更为显著。4)凋落物分解速率受生物及非生物因子的影响,相关分析表明:冷蒿、无芒隐子草、木地肤与土壤微生物量碳呈极显著正相关(P0.01);冷蒿、木地肤、短花针茅与土壤微生物量氮呈极显著正相关(P0.01);木地肤和短花针茅与土壤含水量呈极显著正相关(P0.01);冷蒿、木地肤、短花针茅与地上生物量呈极显著正相关(P0.01)。     

Leaf-shape variation of Paederia foetida in Japan: reexamination of the small, narrow leaf form from Miyajima Island

Variations in Paederia foetida L. leaf shape were examined to evaluate the taxonomic validity of the small, narrow leaf form of P. foetida f. microphylla Honda from Miyajima Island, Honshu, Japan. There is considerable variation in P. foetida individuals in terms of leaf size and leaf index (leaf length:leaf width ratio). On Miyajima Island, some individuals have narrow leaves with a high leaf index value, a phenotype represented by the type specimen of P. foetida f. microphylla, and some do not. Given that the leaf size of individuals from Miyajima Island is smaller than that of individuals from other localities in Japan, and that the small leaf phenotype is stable even under cultivation, P. foetida f. microphylla is classified as the form having the smallest leaf size. Anatomical examination of leaf blades revealed that the large variation in leaf size was attributable to variation in the number of leaf cells but not to differences in cell size or cell shape. Based on these results, we discuss the endemism of P. foetida f. microphylla.     

Antimicrobial activity of saponin fractions of the leaves of Gymnema sylvestre and Eclipta prostrata

The antimicrobial activity of saponin fractions from the leaves of Gymnema sylvestre and Eclipta prostrata was evaluated against pathogenic bacteria and fungi in an in vitro condition. A series of concentrations of crude and pure saponin fractions were tested for antimicrobial activity by zone of inhibition method. The pure saponin fractions were found to be more effective against tested bacterial pathogens when compared to crude saponin fractions. The minimum inhibitory concentration (MIC) exhibited by the pure saponin fraction of G. sylvestre was found to be in the range of 600–1,200 mg/l against bacterial strains and 1,400 mg/l for fungal isolates. In the case of E. prostrata, the range was 1,000–1,200 mg/l for bacteria and 1,400 mg/l for fungal isolates. The susceptibility of bacterial pathogens for saponin fractions was in the order of P. aeruginosa, E. coli, S. typhi, K. pneumoniae, P. mirablis, S. aureus and for fungal pathogens A. fumigatus followed by A. niger and A. flavus. Whereas, A. niger was more susceptible to inhibition by E. prostrata saponin fractions, followed by A. flavus and A. fumigatus. The antimicrobial potential of saponin fractions was compared with antibiotics, Chloramphenicol and Amphotericin-B with respect to bacteria and fungi. The present study suggests that the saponin fractions G. sylvestre and E. prostrata possess significant antibacterial and antifungal activity. Our results further suggest that saponins of G. sylvestre and E. prostrata can be used as a potential fungicide against pathogenic fungi.     

乡土植物白刺花对紫茎泽兰化感作用的响应

为了解乡土植物白刺花对紫茎泽兰化感作用的耐受程度及抵御机理,以2—3年生紫茎泽兰叶片为供体材料,用不同浓度的紫茎泽兰叶片浸提液处理白刺花种子及幼苗。结果表明:紫茎泽兰叶片浸提液对白刺花的影响为低浓度促进,高浓度抑制。当浓度为0.5%时促进效应最强,当浓度大于2.0%时抑制效应明显增加。白刺花种子萌发速率比萌发率对紫茎泽兰化感作用反应敏感,胚轴比胚根敏感,随着幼苗的生长,其抵御紫茎泽兰化感作用的能力逐渐增强,丙二醛的含量与植株生长响应规律相对应,并且经紫茎泽兰浸提液处理能极大的增加白刺花幼苗菌根率,缩短菌根形成的时间。     

砂生槐的一新变型——白花砂生槐

描述了豆科苦参属砂生槐的一个新变型:白花砂生槐[Sophora moorcroftiana(Benth.)Baker f.albiflora S.H.Yang]。原变型的花冠为蓝紫色,而新变型的花冠为白色。     

Matrine-Type Alkaloids from the Seeds of Sophora alopecuroides and Their Potential Anti-inflammatory Activities

Three new matrine-type alkaloids, 8β-hydroxyoxysophoridine ( 1 ), 9β-hydroxysophoridine ( 2 ), 9β-hydroxyisosophocarpine ( 3 ), together with one known analog, 11,12-dehydromatrine ( 4 ), were isolated from the seeds of Sophora alopecuroides L. The structures of new compounds were elucidated using extensive spectroscopic techniques including the experimental and calculated ECD data. The anti-inflammatory activities of all the isolates on NO production in RAW 264.7 cells stimulated by lipopolysaccharide were evaluated. Among them, 8β-hydroxyoxysophoridine ( 1 ) showed a significant inhibitory effect with an IC₅₀ value of 18.26 μM.     

Floral ontogeny in Sophoreae (Leguminosae: Papilionoideae): II. Sophora sensu lato (Sophora group)

Floral ontogeny is described in eight species of Sophora sensu lato, representing the Sophora group, as part of a comparative ontogenetic analysis of Polhill's eight groups of tribe Sophoreae, subfamily Papilionoideae. This tribe includes taxa having relatively unspecialized floral structure. Flowers have a five-lobed calyx, a corolla of five free petals, ten mostly unfused, identical stamens, and a carpel. Order of initiation is predominantly acropetal (except for the carpel): sepals, petals, outer stamens plus carpel, inner stamens. Order of initiation within each whorl is unidirectional from the abaxial side. Overlapping initiation among whorls occurs only in S. chrysophylla. Keel petals are slightly fused in six species, and wing petals are fused in 5. tomentosa. Two bird-pollinated species (S. chrysophylla, S. microphylla) lack the papilionaceous corolla of other species, and their petals are unusually long and lack wing sculpturing found in the others. Other floral differences among species mostly involve flower color, differing absolute or relative sizes among organs, and degree of reflexing of vexillum. All but S. davidii have a hypanthium, which develops very late, starting when the bud is about 5 mm long. The distinctions among species (petal size, degree of reflexed position of vexillum, petal sculpturing, color, anther shape, filament hairs, hypanthium presence, calyx lobing) tend to be expressed late in ontogeny.