Adaptive significances of sexual system in andromonoecious Capparis spinosa (Capparaceae)

The sexual system of the perennial shrub Capparis spinosa L. (Capparaceae), which is distributed in arid deserts of northern Xinjiang, was investigated. The main results can be summarized as follows. (1) The species is andromonoecious, i.e. individuals possess both male and perfect flowers. Stamens of two floral morphs are normal and can be divided into long and short ones in each flower. The perfect flowers have well developed pistils, but male flowers have aborted pistils and only function as males. (2) There were very significant differ-ences among the populations in daily ratio of the two floral morphs, number of long and short stamens of perfect flowers and length of filaments and anthers of short stamens in male flowers (P<0.01), but no significant differ-ences occurred in biomass of floral organ (P>0.05). (3) Anthesis was nocturnal and lasted 15–16 h. Both male and perfect flowers opened about 18:00 at dusk. The number of two floral morphs produced on each individual was indeterminate every day during flowering, which would make the individual temporally androdioecious. However, the total number of male flowers was more than that of perfect flowers within the population every day. (4) The P/O ratios of perfect flowers in three populations were 1.57×104, 1.65×104 and 1.71×104. There was no significant difference in pollen numbers (P>0.05) within population between male and perfect flowers or between long and short stamens, and also no significant difference among the populations in pollen numbers of male and perfect flowers, and in ovule numbers and P/O ratios of perfect flowers (P>0.05). (5) Dynamic curves of pollen viability of long and short stamens in the two floral morphs were similar in three populations. Pollen longevity of both long and short stamens was about 18–20 h, and duration of stigmatic receptivity was about 16–18 h. (6) Floral visitors were hymenopterous and lepidopterous insects. There was a total of seven species of floral visitors in the three populations. The activities of them were greatly affected by the climate of the desert environment. (7) Perfect flowers were not apomictic and could produce fruits after self-pollination (autogamy and geitonogamy) and cross-pollination; thus they had a mixed mating system. These results suggest that the sexual system of andro-monoecy may reflect an environment-heredity interaction in C. spinosa. The male flowers increase the number of pollen grains, the P/O ratio and enhance male fitness of individuals. They also increase the floral display and consequently effect cross pollination by attracting more pollinators that bring cross-pollen to the stigmas of per-fect flowers, thus increase outcrossing rate and female fitness of individuals, which insure reproductive success of C. spinosa in the extreme desert environment.     

青藏高原地区刺山柑解剖特征研究

采用石蜡切片法对分布于海拔4 000 m的西藏札达的刺山柑解剖结构进行研究,进一步探讨青藏高原植物独特生理结构及其与环境的适应性。结果表明刺山柑具有适应高山荒漠草原环境的典型结构特征: 次生根周皮发达,具有较厚的木栓层和发达的次生木质部;茎具表皮毛和角质层,皮层较厚,厚角组织发达,髓较小;叶具角质层,气孔密集,栅栏组织多层,为双栅型等面叶;花冠较大,白色花瓣,适于虫媒传粉;侧膜胎座,子房多室,胚珠多数,花粉外壁较厚,具较强的抗腐蚀及抗酸碱性能。刺山柑形成上述结构特征是青藏高原特殊综合生态环境长期作用的结果。同时也是刺山柑对高原环境的高度适应。     

刺山柑化学成分研究

采用硅胶、聚酰胺和Sephadex LH-20等色谱方法从维吾尔药刺山柑中分离得到11个化学成分,通过理化手段及波谱技术分别鉴定为正二十八烷(1)、β-胡萝卜苷(2)、正二十八烷醇(3)、正三十二烷酸(4)、正十六烷酸(5)、琥珀酸(6)、原儿茶酸(7)4、-羟基-5-甲基呋喃-3-羧酸(8)、山萘酚3-O-β-D-芸香糖苷(9)、芦丁(10)和水苏碱(11)。其中化合物13、和4为首次从该属植物中分离得到。     

Intraspecific variation and evolutionary trends in Capparis spinosa L. (Capparaceae)

 In order to investigate the variability of the polymorphic Capparis spinosa L., a comparative study was carried out in Sicily on subsp. spinosa and subsp. rupestris. Autecology, phenology, quantitative morphology, plant architecture and leaf development of several populations were examined. These data reveal a parapatric distribution of the two subspecies and support their present taxonomic treatment. Subsp. spinosa is widespread on clay soils and shows remarkable intrapopulational variation. It is characterized by shortened reproductive and vegetative periods, high shoot growth rate, winter-desiccating shoot system and stipular thorns. Subsp. rupestris, less variable and linked with carbonatic and volcanic outcrops, shows prolonged phenological patterns, slow growth rate, woody habit and caducous stipules. A noteworthy phenotypic convergence with subsp. rupestris was observed in individuals of subsp. spinosa growing in rocky habitats. The evolutionary trends of Capparis spinosa in the Mediterranean region are discussed. Received March 29, 2000 Accepted April 6, 2001     

药用植物刺山柑愈伤组织诱导及细胞生长代谢特征研究

本文研究了不同外植体及激素对刺山柑愈伤组织诱导的影响,不同激素配比对愈伤组织增殖培养以及悬浮细胞的生长与代谢特征。结果表明:以刺山柑叶片作为诱导愈伤组织的材料,效果较佳;愈伤组织诱导和继代的适宜培养条件是分别是MS 0.5mg/L 2,4-D 1.0mg/L6-BA和MS 1.0mg/L2,4-D 1.5mg/L6-BA。刺山柑悬浮培养细胞的生长周期为30天左右,细胞生长曲线呈"S"形,生物量增长2.8倍左右;细胞生长周期内,碳源消耗规律表现为蔗糖和可溶性总糖的浓度持续降低,而还原糖则表现为先升高后降低;过氧化物酶活测定显示酶活水平与蔗糖浓度的高低呈一定程度的正相关。     

药用植物刺山柑愈伤组织诱导及细胞生长代谢特征研究

本文研究了不同外植体及激素对刺山柑愈伤组织诱导的影响,不同激素配比对愈伤组织增殖培养以及悬浮细胞的生长与代谢特征.结果表明:以刺山柑叶片作为诱导愈伤组织的材料,效果较佳;愈伤组织诱导和继代的适宜培养条件是分别是MS+0.5 mg/L 2,4-D+1.0mg/L6-BA和MS+1.0mg/L2,4-D+1.5mg/L6-BA.刺山柑悬浮培养细胞的生长周期为30天左右,细胞生长曲线呈"S"形,生物量增长2.8倍左右;细胞生长周期内,碳源消耗规律表现为蔗糖和可溶性总糖的浓度持续降低,而还原糖则表现为先升高后降低;过氧化物酶活测定显示酶活水平与蔗糖浓度的高低呈一定程度的正相关.     

Phenological growth stages of caper plant (Capparis spinosa L.) according to the Biologische Bundesanstalt,Bundessortenamt and CHemical scale

Capparis spinosa is an evergreen perennial shrub known from ancient times. During the last years it has been intensively studied because of its multiple uses. The phenological growth stages of caper plant were described using the BBCH scale (Biologische Bundesanstalt, Bundessortenamt and CHemical industry). The decimal code established nine principal growth stages using a two‐digit numerical system, and every major stage was in turn subdivided into secondary growth stages.     

Isolation of Two Plasticizers,Bis(2-ethylhexyl) Terephthalate and Bis(2-ethylhexyl) Phthalate,from Capparis spinosa L. Leaves

Many plants have been known to be contaminated and accumulate plasticizers from the environment, including water sources, soil, and atmosphere. Plasticizers are used to confer elasticity and flexibility to various fiber and plastic products. Consumption of plasticizers can lead to many adverse effects on human health, including reproductive and developmental toxicity, endocrine disruption, and cancer. Herein, we report for the first time that two plasticizers, bis(2-ethylhexyl) terephthalate (DEHT) and bis(2-ethylhexyl) phthalate (DEHP), have been isolated from the leaves of Capparis spinosa L. (the caper bush), a plant that is widely used in food seasonings and traditional medicine. 297 mg/kg of DEHT and 48 mg/kg of DEHP were isolated from dried and grounded C. spinosa L. leaves using column chromatography and semi-preparative high-performance liquid chromatography. Our study adds to the increase in the detection of plasticizers in our food and medicinal plants and to the alarming concern about their potential adverse effects on human health.     

Association between chloroplast DNA and mitochondrial DNA haplotypes in Prunus spinosa L. (Rosaceae) populations across Europe

Chloroplast DNA (cpDNA) and mitochondrial DNA (mtDNA) were studied in 24 populations of Prunus spinosa sampled across Europe. The cpDNA and mtDNA fragments were amplified using universal primers and subsequently digested with restriction enzymes to obtain the polymorphisms. Combinations of all the polymorphisms resulted in 33 cpDNA haplotypes and two mtDNA haplotypes. Strict association between the cpDNA haplotypes and the mtDNA haplotypes was detected in most cases, indicating conjoint inheritance of the two genomes. The most frequent and abundant cpDNA haplotype (C20; frequency, 51 %) is always associated with the more frequent and abundant mtDNA haplotype (M1; frequency, 84 %). All but two of the cpDNA haplotypes associated with the less frequent mtDNA haplotype (M2) are private haplotypes. These private haplotypes are phylogenetically related but geographically unrelated. They form a separate cluster on the minimum-length spanning tree.     

Using genetic structure data and phylogenetic criteria in attributing prioritization scores for conservation of spontaneous Capparis spinosa L. populations from Tunisia

In Tunisia, the increasing pharmacological demand for spontaneous capers is actually leading to progressive forest overexploitation and genetic erosion of the species that is actually represented by scattered populations. Therefore, inventories with emphasis on the characterization, management and conservation of this medicinal plant are becoming a great need.In this work, genetic and phylogenetic criteria based on isozyme markers were used for the prioritization of spontaneous Capparis spinosa L. populations for conservation according to Vane-Wright and collaborators taxic method.Enzymatic loci varied in their ability to detect variation and population analyses indicated that most of the variation is partitioned between rather than within populations. Fst, gene flow values, PCA and cluster analysis also revealed significant differentiation between all populations.When combing phylogenetic and genetic criteria we were able to prioritize some of the populations for conservation. Therefore, the standardization and the summatory of all indices indicated that the populations Nebeur, Nahli and Dyr rank as a priority for conservation.So far, results of the present study appear to justify the in situ conservation strategy, where core areas completely free from perturbation would be defined for the populations with the highest priority for conservation, with the populations presenting unique alleles. This would guarantee the maintenance of most of the species’ genetic variation. The ex situ conservation management strategy would imply the setting up of specialized nurseries and national collections that are still missing in the country to counteract population fragmentation, demographic loss and genetic erosion threatening such spontaneous populations.     

Assessment of variability among morphological and molecular characters in wild populations of mint [Mentha longifolia (L.) L.] germplasm

Mentha longifolia is an important medicinal and aromatic perennial herb that exhibits wide distribution range from sub-tropical to temperate regions. In the present study, agro-morphological traits and genetic differences in 19 different populations of M. longifolia were studied to evaluate the level and extent of its diversity. Analysis of variance (ANOVA) showed that the different phenotypic characters show considerable differences among various populations and was significant at p < 0.05. Molecular diversity analysis performed by using arbitrary amplified eleven ISSR primers generated a total of 121 amplicons that range within the size of 200–2500 base pairs (bp). Each primer on average generated 11 amplicons with percentage polymorphism being 100. The analysis of molecular variance (AMOVA) showed more (64%) among population genetic diversity and less (36%) within the populations. Greater genetic differentiation (Gst = 0.6852) among these populations occurs due to low gene flow (Nm = 0.2297) and greater habitat variability. Geographic and genetic distances were positively correlated according to Mantel’s test. In order to remove any kind of biases, we used R software to perform cluster and redundancy analysis to analyse the extent of relatedness among studied populations. In terms of morphological and molecular aspects, the populations were grouped into four and five clusters respectively based on hierarchical clustering method. The results demonstrated that M. longifolia displays a great degree of morphological and genetic variation and can be utilized in breeding, genetic improvement, and gene bank conservation programmes in future.     

半夏种内居群形态变异的模糊聚类分析

在同一栽培条件下,对主要引自长江中下游地区的１５个半夏〔Ｐｉｎｅｌｉａｔｅｒｎａｔａ（Ｔｈｕｎｂ．）Ｂｒｅｉｔ．〕居群的１６个主要形态性状进行模糊聚类分析,在置信水平λ＝０．６７６４时,将１５个居群划分成４个类型：（１）双珠芽类型：主要形态特征为叶柄上均具双珠芽,但叶型和块茎形状变异较小;（２）普通类型：主要形态特征为叶柄上均只着生单珠芽,但叶型和块茎形状变异较大;（３）长茎类型：主要形态特征为叶柄上具单珠芽,但着生位置较低,块茎呈矩圆形;（４）复合类型：主要形态特征为叶柄上具单珠芽,但居群内常有双珠芽个体出现。     

Genetic structure of French populations of the mountain butterfly Parnassius mnemosyne L. (Lepidoptera: Papilionidae)

Geographical variation in allozyme frequencies among 24 populations of the butterfly Parnassius mnemosyne in southern France was studied by enzyme electrophoresis. Clustering procedures were used to define the geographical organization of genetic variation and an analysis of genetic differentiation was performed to test the degree of potential gene flow between the colonies using the methodologies derived from F-statistics and the private alleles model. Further, an approach using reduced space ordinations (factorial analysis of correspondences and discriminant analysis), was used to allow the visualization of genetically intermediate populations and to determine the rôles of individual alleles at various levels of geographical structure. In P. mnemosyne , the effect of both isolation by distance and geographical barriers upon gene flow is complex. Some barriers appear to be very efficient, but others, at least as strong geographically, do not act in such a way. Multivariate analyses underlined the progressive transition between some groups while in other instances, a sharp cut was observed without obvious topographical barriers. Ecogeographical data and historical events (such as colonization processes) should probably be taken into account in order to explain the geographical variation of genetic structure.     

Development and characterization of 11 microsatellite markers in a widespread Neotropical seasonally dry forest tree species,Geoffroea spinosa Jacq. (Leguminosae)

Eleven dinucleotide microsatellites were developed in Geoffroea spinosa (Leguminosae), a widespread tree of the seasonally dry Neotropical forests, and characterized on six populations from Peru, Argentina and Paraguay. Four of them amplified on the Peruvian populations only, probably because of mutations in the microsatellite flanking regions in the other populations. Ten microsatellites were found polymorphic, with within population gene diversities ranging from 0.17 to 0.95, and a number of alleles varying from seven to 19. A significant overall genetic differentiation was also found (θ = 0.212; P < 0.01).     

Chloroplast DNA study in wild populations and some cultivars of Prunus avium L.

The PCR-RFLP technique was used to detect chloroplast DNA diversity in wild populations of Prunus avium from five European deciduous forests and some cultivars. A study of 10.8% of the total chloroplast genome detected eight insertion-deletion (indel) mutations, distributed over 12 haplotypes. Six haplotypes (H1, H2, H3, H4, H5 and H6) were found in wild populations and eight (H2, H6, H7, H8, H9, H10, H11 and H12) in the cultivars. Only two haplotypes (H2 and H6) are shared by the wild populations and the cultivars. The most-abundant and frequent haplotype in wild populations is H2 (frequency=78%). The wider geographical distribution along with the high frequency reflects its ancient origin. Of the five populations, three are polymorphic. Populations GA (Scotland) and KE (Germany) have unique haplotypes. The total cpDNA diversity in wild populations is h_T=0.40, and a major portion of it is within populations (h_S=0.37). The genetic differentiation among populations was low (G_STC=0.08) and no genetic structure among wild populations was observed. A minimum-length spanning tree, demonstrating relationships among the haplotypes in wild populations, indicated two possible chloroplast lineages. The ten identified cultivars were represented by seven haplotypes; this result proposes the possible utilisation of the PCR-RFLP technique for the characterisation of sweet cherry cultivars. The cpDNA diversity in P. avium should be considered carefully for phylogenetic studies involving this species. Received: 10 July 2000 / Accepted: 19 October 2000     

Modeling population viability of captive elephants in Myanmar (Burma): implications for wild populations

Captive Asian elephants Elephas maximus , used as work animals, constitute up to 22–30% of remaining Asian elephants. Myanmar has the largest captive population worldwide (∼6000), maintained at this level for over a century. We used published demographic data to assess the viability of this captive population. We tested how this population can be self-sustained, how many elephants must be supplemented from the wild to maintain it, and what consequences live capture may have for Myanmar's wild population. Our results demonstrate that the current captive population is not self-sustaining because mortality is too high and birth rates are too low. Our models also suggest ∼100 elephants year⁻¹ have been captured in the wild to supplement the captive population. Such supplementation cannot be supported by a wild population of fewer than 4000 elephants. Given the most recent expert estimate of ∼2000 wild elephants remaining in Myanmar, a harvest of 100 elephants year⁻¹ could result in extinction of the wild population in 31 years. Continued live capture threatens the survival of wild and captive populations and must stop. In addition, captive breeding should be increased. These measures are essential to slow the decline and extinction of all of Myanmar's elephants.     

Genetic diversity and population dynamic of Ziziphus jujuba var. spinosa (Bunge) Hu ex H. F. Chow in Central China

Phylogeographic research concerning Central China has been rarely conducted. Population genetic and phylogeography of Ziziphus jujuba var. spinosa (also called sour jujube) were investigated to improve our understanding of plant phylogeographic patterns in Central China. Single‐copy nuclear gene markers and complete chloroplast genome data were applied to 328 individuals collected from 21 natural populations of sour jujube in China. Nucleotide variation of sour jujube was relatively high (π = 0.00720, θ _w = 0.00925), which resulted from the mating system and complex population dynamics. Analysis of molecular variation analysis revealed that most of the total variation was attributed to variation within populations, and a high level of genetic differentiation among populations was detected (F _st = 0.197). Relatively low long‐distance dispersal capability and vitality of pollen contributed to high genetic differentiation among populations. Differences in the environmental conditions and long distance among populations further restricted gene flow. Structure clustering analysis uncovered intraspecific divergence between central and marginal populations. Migrate analysis found a high level of gene flow between these two intraspecific groups. Bayesian skyline plot detected population expansion of these two intraspecific groups. Network and phylogeny analysis of chloroplast haplotypes also found intraspecific divergence, and the divergence time was estimated to occur at about 55.86 Ma. Haplotype native to the Loess Plateau was more ancient, and multiple glacial refugia of sour jujube were found to locate at the Loess Plateau, areas adjacent to the Qinling Mountains and Tianmu Mountains. Species distribution model analysis found a typical contraction‐expansion model corresponding to the Quaternary climatic oscillations. In the future, the distribution of sour jujube may shift to high‐latitude areas. This study provides new insights for phylogeographic research of temperate plant species distributed in Central China and sets a solid foundation for the application of the scientific management strategy of Z. jujuba var. spinosa.     

Identification and characterization of eight microsatellite loci in Aster amellus L. (Asteraceae)

Eight polymorphic microsatellites were developed in the perennial herbaceous Aster amellus L. (Asteraceae) and characterized on three populations from France and Switzerland. The number of alleles ranged between four and 30 depending on the locus, and the mean number of effective alleles was 5.8. The average gene diversity equalled 0.744 (range: 0.419–0.957) and the overall differentiation was found significant (θ = 0.092, P < 0.01). Three loci displayed significant heterozygote deficiencies, which might indicate the presence of null alleles. Amplifications were detected on eight loci in Aster alpinus L.     

Genealogical exclusivity in geographically proximate populations of Hypochilus thorelli Marx (Araneae,Hypochilidae) on the Cumberland Plateau of North America

The issue of sampling sufficiency is too infrequently explored in phylogeographical analysis, despite both theoretical work and analytical methods that stress the importance of sampling effort. Regarding the evolutionary pattern of reciprocal monophyly, both the probability of recovering this pattern and the possible inferences derived from this pattern, are highly contingent upon the density and geographical scale of sampling. Here, we present an empirical example that relates directly to this issue. We analyse genetic structure in the southern Appalachian spider Hypochilus thorelli, using an average sample of 5 mitochondrial DNA (mtDNA) sequences per location for 19 locations. All sampled sites are reciprocally monophyletic for mtDNA variation, even when separated by geographical distances as small as 5 km. For populations separated by greater geographical distances of 20-50 km, mtDNA sequences are not only exclusive, but are also highly divergent (uncorrected p-distances exceeding 5%). Although these extreme genealogical patterns are most seemingly consistent with a complete isolation model, both a coalescent method and nested cladistic analysis suggest that other restricted, but nonzero, gene flow models may also apply. Hypochilus thorelli appears to have maintained morphological cohesion despite this limited female-based gene flow, suggesting a pattern of stasis similar to that observed at higher taxonomic levels in Hypochilus.