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1.
2.
To study the reproductive system of the putative autogamous species Anthyllis vulneraria in Belgian calcareous grasslands, eight polymorphic microsatellite loci were developed using the sequence‐tagged microsatellite profiling technique and 35 plants were typed for all loci. No linkage disequilibrium was found between any pair of loci. Over the loci, the number of alleles ranged from two to five. Observed and expected heterozygosities ranged from 0.053 to 0.688 and from 0.053 to 0.631, respectively. The estimated FIS values (FIS = 0.031 and 0.122) are not in accordance with a predominantly selfing reproductive system.  相似文献   

3.
In spite of being widely distributed throughout Europe, populations of Anthyllis vulneraria are very isolated genetically. As a consequence of processes of independent evolution, some isolated populations have developed characteristics that separate them from the rest. The scope of this study was to investigate whether or not this isolation has affected the reproductive biology. The reproductive biology of an isolated population of A. vulneraria subsp. vulgaris (Koch) Willk. in northwest Spain was studied, and compared with French populations. In the studied population, insect pollination was necessary for fruit production. Autogamy was precluded by protandry, although geitonogamous pollen transfer might occur. Supplementary pollination did not lead to any increase in fruit-set level, seed-pod weight or seed weight. Mean pollen/ovule ratio (3080) was within the normal range for xenogamous taxa. The first open flowers in capitula lived more than twice as long as later flowers did. During the floral life-span, corolla colour gradually changed from white to partially pink to pink and the nectar production rate appeared to differ between colour stages. Fruit set level in the studied population differed between the four years of study. The breeding system found in this Spanish population differs from French populations. I suggest that classification of this taxon in northwest Iberian Peninsula should be reconsidered, taking into account its breeding system.  相似文献   

4.
Very little is known about the genetic diversity and phylogeny of rhizobia nodulating Lotus species in northern temperate regions. We have therefore studied the genetic diversity among a total of 61 root nodule bacteria isolated from Lotus corniculatus and Anthyllis vulneraria from different geographic sites and habitats in Sweden by restriction fragment length polymorphism (RFLP) of the internal transcribed spacer between their 16S rRNA and 23S rRNA (IGS) region. A high diversity consisting of 26 IGS types from 54 L. corniculatus isolates and five IGS types from seven A. vulneraria isolates was found. The 16S rRNA sequences and phylogeny of representatives of the different IGS types showed four interesting exceptions from the majority of the isolates belonging to the genus Mesorhizobium: Two isolates were both found to be closely related to Rhodococcus spp., and two other isolates showed close relationship with Geobacillus spp. and Paenibacillus spp., respectively. The nodA sequences and phylogeny showed that all the isolates, including those not belonging to the traditional rhizobia genera, harbored nodA sequences which were typical of Mesorhizobium loti. Generally, the 16S rRNA and nodA phylogenetic trees were not congruent in that isolates with similar 16S rRNA sequences were associated with isolates harboring different nodA sequences. All the isolates were confirmed to nodulate L. corniculatus in an inoculation test. This is the first report of members of these non-rhizobia genera being able to nodulate legumes, and we suggest that they may have acquired their nodulating properties through lateral gene transfer.  相似文献   

5.
This paper examines the hypothesis that nectar robbing can affect plant reproductive success either positively or negatively. To this end, I investigated various aspects of the pollination ecology of a population of the herb Anthyllis vulneraria subsp. vulgaris in northwest Spain over 5 yr. By observing floral visitors, I found that the most important pollinator species was the long-tongued bee Anthophora acervorum, which accounted for ~45% of recorded insect visits. However, just over 45% of visits were by the nectar-robbing bumble bees Bombus terrestris and B. jonellus. Although the incidence of robbing differed considerably over 5 yr of study, the frequency in every season was very high (66.4-76.5% of robbing) except for 1997 (0% robbing). Despite this high frequency of robbing, robbed flowers had a higher probability of setting fruit than nonrobbed flowers in all years of the study (mean: 82.0 vs. 51.0%; excluding 1997). This increased fruit set in robbed flowers is directly related to bumble bee behavior because the robbers' bodies came into contact with both the anthers and stigmas while robbing. Thus, the robbers effect pollination. These results suggest that the effect of nectar robbers on plant reproductive success is dependent both on the robbers' behavior and on flower/inflorescence structure. The importance of nectar-robbing bumble bees on the reproductive success of A. vulneraria and its yearly high frequency suggest that the relationship between robbers and this plant is part of a successful long-term mutualism.  相似文献   

6.
The abundant centre model (ACM) predicts that the suitability of environmental conditions for a species decreases from the centre of its distribution toward its range periphery and, consequently, its populations will become scarcer, smaller and more isolated, resulting in lower genetic diversity and increased differentiation. However, little is known about whether genetic diversity shows similar patterns along elevational and latitudinal gradients with similar changes in important environmental conditions. Using microsatellite markers, we studied the genetic diversity and structure of 20 populations each of Anthyllis vulneraria along elevational gradients in the Alps from the valleys to the elevational limit (2500 m) and along a latitudinal gradient (2500 km) from Central Europe to the range margin in northern Scandinavia. Both types of gradients corresponded to an 11.5°C difference in mean annual temperature. Genetic diversity strongly declined and differentiation increased with latitude in line with the predictions of the ACM. However, as population size did not decline with latitude and genetic diversity was not related to population size in A. vulneraria, this pattern is not likely to be due to less favorable conditions in the North, but due to serial founder effects during the post‐glacial recolonization process. Genetic diversity was not related to elevation, but we found significant isolation by distance along both gradients, although the elevational gradient was shorter by orders of magnitude. Subarctic populations differed genetically from alpine populations indicating that the northern populations did not originate from high elevational Alpine ones. Our results support the notion that postglacial latitudinal colonization over large distances resulted in a larger loss of genetic diversity than elevational range shifts. The lack of genetic diversity in subarctic populations may threaten their long‐term persistence in the face of climate change, whereas alpine populations could benefit from gene flow from low‐elevation populations.  相似文献   

7.
Plant's infection with soil bacteria Agrobacterium tumefaciens lead to tumour formation, so called crown galls. The reason of tumorigenesis is integration of agrobacterial genes for phytohormone synthesis auxins and cytokinins in plant genome, the most important of them are iaaM and ipt. Obtaining of transgenic plants able to inhibit these genes expression, creates conditions for producing of plants resistant to crown gall disease. With this purpose single and double transformants of tobacco plants with antisense copies of iaaM and ipt genes under the control of single and double promoters of 35S RNA of cauliflower mosaic virus (CaMV 35S and CaMV 35SS) were produced. Infection with virulentA. tumefaciens strains C58 (pTiC58) and A6 (pTiA6) of all types transgenic plants with antisense oncogenes copies showed essential but incomplete inhibition of these genes expression. After agrobacterial transformations of transgenic plants only "weakened" tumours of various morphology, able to regenerate the whole plants, were formed. The analysis data of inhibition of iaaM and ipt genes expression in formed tumour cells were presented. The results indicate perspective RNA-interference strategy for producing of plants resistant to agrobacterial crown gall disease.  相似文献   

8.
This present paper studies the response of Anthyllis vulneraria-Rhizobium symbiosis to heavy metal stress. The symbiotic rhizobium bacteria isolated from root nodules of A. vulneraria from zinc and lead wastes were examined in this project. Light microscopy (LM) and transmission electron microscopy (TEM) were used to analyze the nodule anatomy and ultrastructure and conduct a comparison with nonmetal-treated nodules. 16S ribosomal DNA sequence analysis of bacteria isolated from metal-treated nodules revealed the presence of Rhizobium metallidurans and Bradyrhizobium sp. In regard to heavy metal resistance/tolerance, a similar tolerance to Pb was shown by both strains, and a high tolerance to Zn and a lower tolerance to Cd and Cu by R. metallidurans, whereas a high tolerance to Cd and Cu and a lower tolerance to Zn by Bradyrhizobium were found. The nodules of Anthyllis from metal-polluted tailing sites were identified as the typical determinate type of nodules. Observed under TEM microscopy changes in nodules ultrastructure like: (1) wall thickening; (2) infection thread reduction; (3) vacuole shrinkage; (4) synthesis of phenolics in vacuoles; (5) various differentiation of bacteroids and (6) simultaneous symbiosis with arbuscular mycorrhiza fungi could be considered as a form of the A.vulneraria-Rhizobium symbiosis adaptation to metal stress.  相似文献   

9.
Restoration of metalliferous mine soils requires using plant species tolerant to high metal concentrations and adapted to nutrient‐poor soil. Legumes can increase plant productivity through N2‐fixation, but they are often scarce in metalliferous sites. We examined survival, growth, and tolerance of four populations of a legume, Anthyllis vulneraria, from two metalliferous (MET) Zn‐Pb mine sites, Avinières (AV) ([Zn‐EDTA] = 26,000 mg/kg) and Eylie (EY) ([Zn‐EDTA] = 4,632 mg/kg), and two non‐metalliferous (NMET) sites located in the south of France with the aim to select the most appropriate populations for restoration of mined soils. In a common garden experiment, plants from each population were reciprocally grown in soil from the provenance of each population. The two NMET populations exhibited high mortality and low growth rates in soil from the mined sites. The AV MET exhibited a high growth rate in metalliferous soils, but showed high mortality in non‐metalliferous soils. The growth of the EY MET was very low in the AV‐contaminated soil, but was the highest of all populations in moderately and non‐metalliferous soils. Plants from the AV MET population showed a high growth and survival in metalliferous soil and would be appropriate in the restoration of metal‐contaminated sites (>30,000 mg Zn kg?1). The EY MET population would be adapted to the restoration of moderate metal‐contaminated soils (<30,000 mg Zn kg?1). Taking into account the broad distribution of A. vulneraria, these two populations could be suitable for the restoration of derelict mine sites in mediterranean and temperate regions of Europe and North America.  相似文献   

10.
The Vavilov Institute of Plant Industry (VIR) keeps a living seed collection of about 700 accessions of landraces and local cultivars of common vetch ( Vicia sativa L.) that have been collected over a period of more than 50 years throughout the former USSR. Much of the material is available nowhere else. The collection of this economically important fodder crop is well adapted to the various growing regions of Russia and serves as a basis for the all domestic vetch breeding programs. Using AFLP as a DNA fingerprinting method we investigated 673 accessions from the VIR and compared their genetic variability with that of the worldwide vetch collection of the Institut für Pflanzengenetik und Kulturpflanzenforschung (IPK), 450 accessions. The analysis is a first assessment of the intra-specific diversity of V. sativa stored ex situ on a scale of more than 1,000 accessions. Six primer combinations, which gave clear polymorphic amplification products with 96 test samples, were chosen from 111 primer combinations tested. The selected AFLP primers used to analyse the V. sativa intra-specific diversity resulted in 70 unequivocally recognizable polymorphic fragments. We found that all of the AFLP fragments generated can be detected with varying frequency throughout the entire distribution area of V. sativa. The difference in frequency of some AFLP fragments between the regions may amount to 90%. The arrangement of most of the accessions in all dendrograms reflects their geographical origin, with a differentiation between Russia, Western Europe, Turkey and Bulgaria, and the Mediterranean. The "Russian" genepool stored at the IPK is a limited and biased sample of the available diversity when compared to the material stored at the VIR. Approximately 10-15% of the accessions in each geographical group showed AFLP patterns that clustered with members of other groups. This appreciable overlap raises several questions: (1) to which degree is an AFLP pattern representative of the overall genetic similarity of the samples; (2) to which degree are samples collected at a site adaptively limited to that site? Since our data identify accessions with very similar AFLP patterns from very diverse geographic origins, a comparison of the agronomic performance of these accessions (possibly in the two regions) will provide important information for the utilization of ex situ germplasm collections.  相似文献   

11.
紫云英还田配施氮肥对稻田土壤碳库的影响   总被引:2,自引:0,他引:2  
  相似文献   

12.

Aims

This work examines Zn accumulation in four Anthyllis vulneraria subspecies supplemented with mineral nitrogen or grown in the presence of their symbiotic bacteria.

Methods

Anthyllis vulneraria subspecies were grown hydroponically in the presence of high levels of ZnSO4. The plants were either grown in symbiosis with one of two non-metallicolous or metallicolous Mesorhizobium inoculants or in the presence of KNO3.

Results

When exposed to 1,000 μM Zn, shoot and root biomass of three out of our four Anthyllis subspecies cultivated with NO3 dropped significantly by about 24–28 %; carpatica, the fourth subspecies, was not affected. Subspecies carpatica Zn tolerance was confirmed when in symbiosis with the metallicolous strain. In the presence of 1,000 μM Zn, the different Anthyllis subspecies concentrated more Zn in their roots than in their shoots and only subsp. carpatica accumulated a significant amount of Zn in its shoots. The most remarkable feature was the drastic decrease in Zn concentration in both roots (up to 2.5–3 fold) and shoots (2.6-fold) of subsp. carpatica exposed to 1,000 μM Zn and nodulated whatever the Mesorhizobium strain used, compared to the N-grown plants.

Conclusions

Our results bring new perspectives as regards phytostabilization, with the potential use of a rhizobium-inoculated leguminous subspecies displaying unusual Zn tolerance.  相似文献   

13.
【目的】长期高强度的连作及大量化肥施用导致红壤旱地退化和土传植物病原菌累积。真菌是农业生态系统中与土壤健康密切相关的微生物。本文通过研究土壤真菌群落的变化,探究施用毛叶苕子对红壤旱地农业生态系统的影响。【方法】采用定量聚合酶链式反应和高通量测序技术,研究红壤旱地真菌群落对单施矿质肥(mineral nitrogen,phosphorus and potassium fertilization,NPK)与矿质肥配施毛叶苕子(mineral nitrogen,phosphorus and potassium fertilization with hairy vetch,NPKG) 2种施肥措施的响应。【结果】与对照NPK相比,NPKG显著提高土壤肥力、花生产量和土壤真菌丰度,降低土壤p H和土壤真菌多样性。不同处理显著改变土壤真菌群落组成。与对照NPK相比,NPKG处理土壤腐生营养型真菌相对丰度显著提高37.42%,花生尾孢菌(Cercospora arachidicola)和可可毛色二孢菌(Lasiodiplodia theobromae) 2种花生病原菌相对丰度分别降低89.11%和8...  相似文献   

14.
Twenty-six experimental populations of A. vulneraria were surveyed for leaf flavonoids. The distribution of 34 flavonol glycosides showed, after factor analysis, the existence of for distinct chemical taxa, each exhibiting characteristic glycosides of 7-methylkaempferol. These results, and others obtained from further factor analysis, are discussed in relation to Couderc's taxonomic studies, and allow a better definition of infraspecific units of A. vulneraria. Flavonoid and morphological data are generally correlated.  相似文献   

15.
Summary The kidney sac of Achatina achatina, the site of primary urine formation, seems to contain no direct structural analogue of the vertebrate glomerular podocytes. The nephrocytes which line the kidney sac and separate the blood from the primary urine are supported by a basal lamina which is permeable to ferritin but impermeable to colloidal gold particles (ca. 100 Å, and 80–240 Å respectively). The blood capillaries within the kidney sac are of two types, fenestrated and unfenestrated. The basal lamina which surrounds them is impermeable to haemocyanin. The nephrocytes are then, bathed apically by primary urine and basally by an ultrafiltrate of the blood. It is proposed that fluid enters the urinary space from the connective tissue by passing between the nephrocytes, perhaps through pores in the septate junctions. Other possible mechanisms of primary urine formation are discussed. The nephrocytes contain peroxisomes which may be involved in urate metabolism.The cells of the ureteral epithelium bear a lumenal microvillous border. Their lateral and basal plasma membranes are elaborately folded. These cytoplasmic folds enclose extracellular channels through which fluid is transported from the urine back into the blood.  相似文献   

16.
Polluted agricultural soils are a serious problem for food safety, with phytoremediation being the most favorable alternative from the environmental perspective. However, this methodology is generally time-consuming and requires the cessation of agriculture. Therefore, the purpose of this study was to evaluate two potential phytoextractor plants (the native species Bidens pilosa and Tagetes minuta) co-cropped with lettuce growing on agricultural lead-polluted soils. The concentrations of Pb, as well as of other metals, were investigated in the phytoextractors, crop species, and in soils, with the potential risk to the health of consumers being estimated. The soil parameters pH, EC, organic matter percentage and bioavailable lead showed a direct relationship with the accumulation of Pb in roots. In addition, the concentration of Pb in roots of native species was closely related to Fe (B. pilosa, r = 0.81; T. minuta r = 0.75), Cu (T. minuta, r = 0.93), Mn (B. pilosa, r = 0.89) and Zn (B. pilosa, r = 0.91; T. minuta, r = 0.91). Our results indicate that the interaction between rhizospheres increased the phytoextraction of lead, which was accompanied by an increase in the biomass of the phytoextractor species. However, the consumption of lettuce still revealed a toxicological risk from Pb in all treatments.  相似文献   

17.
It is important to quantify and understand the consequences of elevated temperature and carbon dioxide (CO2) on reproductive processes and yield to develop suitable agronomic or genetic management for future climates. The objectives of this research work were (a) to quantify the effects of elevated temperature and CO2 on photosynthesis, pollen production, pollen viability, seed‐set, seed number, seeds per pod, seed size, seed yield and dry matter production of kidney bean and (b) to determine if deleterious effects of high temperature on reproductive processes and yield could be compensated by enhanced photosynthesis at elevated CO2 levels. Red kidney bean cv. Montcalm was grown in controlled environments at day/night temperatures ranging from 28/18 to 40/30 °C under ambient (350 µmol mol?1) or elevated (700 µmol mol?1) CO2 levels. There were strong negative relations between temperature over a range of 28/18–40/30 °C and seed‐set (slope, ? 6.5% °C?1) and seed number per pod (? 0.34 °C?1) under both ambient and elevated CO2 levels. Exposure to temperature > 28/18 °C also reduced photosynthesis (? 0.3 and ? 0.9 µmol m?2 s?1 °C?1), seed number (? 2.3 and ? 3.3 °C?1) and seed yield (? 1.1 and ? 1.5 g plant?1 °C?1), at both the CO2 levels (ambient and elevated, respectively). Reduced seed‐set and seed number at high temperatures was primarily owing to decreased pollen production and pollen viability. Elevated CO2 did not affect seed size but temperature > 31/21 °C linearly reduced seed size by 0.07 g °C?1. Elevated CO2 increased photosynthesis and seed yield by approximately 50 and 24%, respectively. There was no beneficial interaction of CO2 and temperature, and CO2 enrichment did not offset the negative effects of high temperatures on reproductive processes and yield. In conclusion, even with beneficial effects of CO2 enrichment, yield losses owing to high temperature (> 34/24 °C) are likely to occur, particularly if high temperatures coincide with sensitive stages of reproductive development.  相似文献   

18.
By means of fluorescent-histochemical method distribution of monoaminergic structures has been studied in the sympatho-adrenal system of the carp (Cyprinus carpio L.) mesonephros. Catecholaminergic nervous fibers are revealed in the walls of adrenal and venous vessels and glomerular arterioles. In the glomerular capillaries they are not found. In the walls of the venous vessels, besides catecholamine-containing nervous fibers, chromaffin cells with long processes running along the vessel are observed. Some contacts of catecholamine-containing structures of the mesonephric vascular wall with the proximal and, very seldom, with distal parts of the nephron canaliculi are demonstrated. Structures containing indolamines are not revealed.  相似文献   

19.
Tiedemann J  Neubohn B  Müntz K 《Planta》2000,211(1):1-12
The temporal and spatial patterns of storage-globulin mobilization were immunohistochemically pursued in the embryonic axis and cotyledons of vetch seed (Vicia sativa L.) during germination and early seedling growth. Embryonic axes as well as cotyledons of mature seeds contain protein bodies with stored globulins. Prevascular strands of axes and cotyledons, the radicle and epidermal layers of axis organs were nearly exclusively stained by vicilin antibodies whereas the cotyledonous storage mesophyll gave similar staining for vicilin and legumin. Globulin breakdown started locally where growth and differentiation commenced in the axis. There, vicilin mobilization preceded legumin mobilization. Thus vicilin represents the initial source of amino acids for early growth and differentiation processes in vetch. Legumin presumably only serves as a bulk amino acid source for subsequent seedling growth during postgerminative globulin degradation. During the first 2–3 d after the start of imbibition the axis was depleted of globulins whereas no decrease in immunostainability was detected in the cotyledons except in their vascular strands where immunostainability was almost completely lost at this time. Continuous vascular strands were established at the third day when globulin breakdown was finished in the axis but had just started in the cotyledon mesophyll. Protein mobilization proceeded in a small zone from the epidermis towards the vascular strands in the center of the cotyledons. In this zone the storage cells, which initially appeared densely packed with starch grains and protein bodies, concomitantly transformed into cells with a large central vacuole and only a thin cytoplasmic layer attached to the cell wall. These results agree well with the hypothesis that during the first 2 d after imbibition the axis is autonomous in amino acid provision. After the endogenous reserves of the axis are depleted and the conductive tissue has differentiated, globulins are mobilized in the cotyledons, suggesting that then the amino acid supply is taken over by the cotyledons. For comparison with other degradation patterns we used garden bean (Phaseolus vulgaris L) and rape (Brassica napus L.) as reference plants. Received: 3 August 1999 / Accepted: 11 December 1999  相似文献   

20.
The fine structure of the kidney is studied in the sexually mature male three-spined stickleback after administration of an antiandrogen, cyproterone acetate. Under these conditions, the dedifferentiation of renal tubules is characterized by the same involutive processes as those induced by castration, with the difference that cyproterone acetate only begins to act after 14 days whereas after castration the first signs of involution are visible after 7 days. The ultrastructural modifications affect the nucleoli, the rough endoplasmic reticulum and the Golgi apparatus. They reflect an inhibition of the secretory process. The results obtained demonstrate that administration of cyproterone acetate to male sticklebacks has an inhibitory effect on renal target cells, apparently indistinguishable from the changes induced by lack of male sex hormone, and that this drug may be a valid substitute for castration in fish.  相似文献   

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