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1.
Eighty-nine accessions of wild and cultivated peas (12 Pisum fulvum Sibth. et Smith., 7 P. abyssinicum A. Br., 31 wild and 42 cultivated forms of P. sativum L.) were analysed for presence of the variants of three functionally unrelated polymorphic markers referring to different cellular genomes. The plastid gene rbcL either contains or not the recognition site for restriction endonuclease AspLEI (rbcL+ vs. rbcL−); the mitochondrial gene cox1 either contains or not the recognition site for restriction endonuclease PsiI (cox1+ vs. cox1−); the nuclear encoded seed albumin SCA is represented by slow (SCAS) or fast (SCAF) variant. Most of the accessions possessed either of two marker combinations: 24 had SCAF cox1+ rbcL+ (combination A) and 49 accessions had SCAS cox1rbcL− (combination B), 16 accessions represented 5 of the rest 6 possible combinations. All accessions of P. fulvum and P. abyssinicum had combination A, the overwhelming majority of cultivated forms of P. sativum had combination B while wild representatives of P. sativum had both combinations A and B, as well as rare combinations. This pattern indicates that combination A is the ancestral state in the genus Pisum L., inherited by P. fulvum and P. abyssinicum, while combination B seems to have arisen in some lineage of wild P. sativum which rapidly fixed mutational transitions of the three markers studied, most probably via a bottleneck effect during the Pleistocene. Then this ‘lineage B’ spread over Mediterranean and also gave rise to cultivated forms of P. sativum. Rare combinations may have resulted from occasional crosses between ‘lineage A’ and ‘lineage B’ in nature or during cultivation, or represent intermediate evolutionary lineages. The latter explanation seems relevant for an Egyptian cultivated form ‘Pisum jomardii Schrank’ (SCAF cox1rbcL−) which is here given a subspecies rank. Wild representatives of P. sativum could be subdivided in two subspecies corresponding to ‘lineage A’ and ‘lineage B’ but all available subspecies names seem to belong to lineage B only. Presently all wild forms would better be considered within a fuzzy paraphyletic subspecies P. sativum subsp. elatius (Bieb.) Schmalh. s. l.  相似文献   

2.
The continued cultivation of Lupinus pilosus L. as an endemic coffee substitute in the mountain village of Altrei, South Tyrol, located in the Val di Fiemme/Fleimstal valley ca. 24 km south of Bolzano/Bozen, since the middle of the nineteenth century is demonstrable. Former reports of cultivation of Lupinus cosentinii Guss. and L. varius auct., non L. for this purpose in Tyrol could refer to L. pilosus as well. The cultural history of the rare crop is summarized up to its recent revival.  相似文献   

3.
We searched for predictive models for alpha, beta and gamma plant diversity based in easy to measure field indicators. The study was conducted on the upper belt of the Córdoba mountains (Argentina). We established 222 permanent plots of 4 × 4 m distributed on sites with different physiognomy, topography and management. At each plot we measured physical and physiognomic indicators and recorded the presence of all vascular plants. We estimated alpha diversity as the number of species detected in a plot, beta diversity as the floristic dissimilarity between two plots, and gamma diversity as the number of species detected in a landscape. Through linear regression we found predictive models for alpha and pair-wise beta diversity. Then we analysed if predicted average alpha and beta diversity were good estimators of gamma diversity. We recorded a total of 288 species (5-74 species per plot). Alpha diversity was highest in sites on shallow soils with high structural richness (i.e. high number of cover categories), half covered by lawns, at sunny slopes and rough landscapes (r2 = 0.66). For beta diversity, the difference between plots in structural richness and in cover of thick tussocks grasses and lawns were the best predictors (r2 = 0.45). For different sets of simulated landscapes, gamma diversity was well explained by predicted average alpha and beta diversity, plus the sampling effort (r2 = 0.92). We concluded that using easy to measure field indicators it is possible to estimate plant diversity at different levels with a good accuracy.  相似文献   

4.
Eryngium caucasicum was found as a new cultivated vegetable plant in home gardens in northern Iran. Young leaves are used as a cooked vegetable and for flavouring in the preparation of several local foods.  相似文献   

5.
Abstract

Studies examining iron (Fe) toxicity and zinc (Zn) deficiency in rice have shown that screening experiments in nutrient solutions are of limited use because the rankings of genotypes as tolerant or intolerant can be very different from the results obtained in field-screening experiments. A possible reason for such deviation is that crucial rhizosphere processes cannot be reproduced in nutrient solutions. The objective of the present study was to evaluate the suitability of low-concentration agar nutrient solutions (ANS) as an alternative screening tool. Agar was dissolved in boiling water and mixed with nutrient solution to achieve a final agar concentration of 0.1% (w/v). Zinc deficiency was induced by supplying Zn at a low concentration (0.1 × 10?3 µmol L?1), while Fe toxicity was induced by supplying excess Fe2+ (200 mg L?1). Three-week-old seedlings were transplanted into this medium. Symptoms of Zn deficiency and Fe toxicity developed more rapidly in ANS compared with conventional nutrient solutions (CNS). For Zn deficiency this was probably because of the development of Zn depletion zones as a result of the reduced convection in the viscous agar medium. In the case of Fe toxicity we observed far less Fe precipitation in ANS compared with CNS. Genotypic comparisons showed that the tolerance rankings obtained in ANS were very similar to the field tolerance rankings, whereas this was not the case in CNS. This was particularly evident with regard to the considerable root growth inhibition detected in intolerant genotypes when stress treatments were imposed in ANS.  相似文献   

6.
The Eurasian black vulture (Aegypius monachus) is a globally endangered species, vulnerable in Europe and endangered in Greece. We modelled its nesting preferences in Dadia reserve, northeastern Greece using logistic models at multi-scale level combined by Bayesian statistics. Compared with the random sites, the vultures nested at trees with greater diameter (DBH), lower height, and lower total number of trees around the nest tree, steeper slopes and greater distance from forest roads. Our results indicate that conservation and management guidelines for black vultures must aim: (1) to preserve old, isolated mature trees in the reserve, (2) to maintain the zones of strict protection as vulture sanctuary, including most of the suitable nesting habitat, (3) to protect the apparently suitable but still unused habitat in the rest of the reserve from disturbance and logging, (4) to monitor any changes in habitats and use our models to evaluate and predict their effect on vulture nesting in the reserve.  相似文献   

7.
Background, aim, and scope  Elevated levels of heavy metals in the aquatic and soil systems can be caused by the weathering of mineralized rocks. This enrichment is often considerably enlarged by historical and current mining and smelting activities. In Poland, the most contaminated river systems are those in the Silesia region. The metalliferous ore mining and smelting industries have been the main sources of heavy metal pollutions over the last 100–170 years. The previous and present studies have shown very high concentrations of heavy metals in the bottom sediments of the Mala Panew River, the most polluted tributary of the Oder River. The main objective of this work was to study temporary changes of selected metal (Zn, Pb, and Cd) concentrations in upper layer of bottom sediments at the measuring point near the outlet of the Mala Panew River into the Oder River, and to determine the vertical distribution of the metals in the sediment cores from the most polluted middle part of this river. The mobility of the metals and their potential bioavailability were assessed based on metal partitioning in the sediments and metal concentrations in pore waters. The presented data were compared with metal concentrations in aquatic sediments from similar historical mining and smelting sites in Poland and other countries. Methods  The upper layer of bottom sediment samples from the same Mala Panew River measuring point were collected six times in the period 1997–2005, while five sediment cores were collected once from the middle course of Mala Panew River in 2006. Abiotic parameters such as pH and Eh have been determined in situ. Metal contents were determined in the <20 and <63 μm size fractions of sediments after digestion in a microwave oven with aqua regia or concentrated nitric acid. Metal mobility was assessed in the selected sediment cores by the chemical forms of metals (sequential extraction method) and their concentrations in pore waters were investigated. Results  The concentrations of Cd, Pb, and Zn in the upper layer of sediments varied, depending on both the season and the year of sampling. Their mean concentrations (from six samplings) are [mg/kg]: Zn 1,846, Pb 229 and Cd 73. The metal concentrations in the sediment cores varied with the depth in the range of [mg/kg]: 0.18–559 for Cd, 26.2–3,309 for Pb and 126–11,153 for Zn, although the highest accumulations generally could be observed in the deeper layers. The most mobile metal fractions, i.e., exchangeable, carbonate and easily reducible fractions, are typical of Zn and Cd. Cadmium was found to be the most mobile metal and its relative contribution ranges from 84 to 96%, while in the case of Zn it ranged from 45 to 94%. Lead is mainly associated with the moderately reducible fraction (30–60%). Relative contributions of metal chemical forms slightly vary with the depth in the sediment profile. The results obtained for the pore water samples show very high concentrations of the metals studied, especially in the case of Cd (31–960 μg/dm3) and Zn (300–4,400 μg/dm3). Discussion  Accumulation of Cd, Pb, and Zn in the upper layer of the bottom sediments and in the sediment core samples from the Mala Panew River is very high, considerably exceeding the local geochemical background. High contributions of mobile Cd and Zn and the toxicity of cadmium can cause environmental risk. Our measurements also suggest that mobile metals can migrate into groundwater, whereas the groundwater itself can leach some chemicals from river sediments, because of a relatively high water table in the study area, especially during rainfall periods. Comparison of the results obtained with the literature data from the last decade shows that the concentrations of Cd and Zn in the sediments from the Mala Panew River are the highest among other submersed sediments in Poland and other regions (e.g., the Mulde River, Germany). Conclusions  The Mala Panew River is one of the most polluted rivers when compared with similar historical mining and smelting areas in Poland and elsewhere. The sediments studied are strongly polluted with the metals analyzed. In the upper layer of the bottom sediments there has been no reduction of Zn and Cd amounts over the last decade, which could suggests a long-term migration and a secondary contamination. Considerably higher accumulations of metals in overbank sediment cores and in the deeper core section could result from strong contamination in previous decades and translocation of Cd and Zn (secondary pollutants). The relatively high concentrations of the two metals in pore waters support these findings. Cadmium is crucial in the environmental risk assessment because of its high mobility and toxicity. These data are important for water/sediment management in the transboundary Oder River catchment, situated in Poland, Germany and the Czech Republic. Recommendations and perspectives  It is important to assess mobility phase and pore water in the contaminated historical aquatic sediments. Such studies may help explain the changes, which take place in the sediment layers as well as at the water–sediment interface. Obtained results should be used for the risk assessment of the historical contaminated sediments at the local river-basin scale. The treatment of contaminated sediments, e.g., dragging activity, should be considered as very important in management strategies in order to avoid remobilization of metals.  相似文献   

8.
Ornamental kale (Brassica oleracea var. Acephala) is usually planted from early autumn until late winter. Since most of the plants used for phytoremediation cannot be grown during this time, kale can be a suitable option for phytoremediation and utilized during autumn and winter in urban landscape, especially in metropolitan areas where high levels of cadmium (Cd) and lead (Pb) pollutions exist. Kale growth in saline soil at different growth stages (germination and vegetative growth stages) was studied in this investigation. A factorial experiment based on completely randomized design (CRD) with four replications was used in this study. Treatments included three levels of sodium chloride (NaCl) (0, 30, and 60 mg/kg), four levels of Cd (0, 4, 8, and 16 mg/kg), and four levels of Pb (0, 1, 5, and 10 mg/kg). Results indicated that increase in Cd and Pb concentrations in the soil decreased fresh and dry weights of the plants. The results of the various growth stages revealed that under salinity stress, kale plants were able to absorb more Pb than Cd and effectively remediate Pb in polluted and saline lands. Cd accumulation in control treatment was 6.2% more than that in the saline treatments, whereas, Pb accumulation in the highest NaCl level, 60 mg/kg salinity treatment was 7.64% more than that of the control condition. Also, proline content of the plants was significantly increased under Cd and Pb stress. From the results of this study, it was concluded that using kale plant is recommended for phytoremediation of saline soils with 10 and 16 mg/kg Pb and Cd contents, respectively.  相似文献   

9.
The effects of conventional and organic (manure) fertilization on soils of vineyards were examined in the area of Nemea in southern Greece. The soil properties of the adjacent natural environment (maquis), which served as a control (considering the land use changes as treatments), were also examined and compared with those of the vineyards. The null hypothesis was that there was no difference among them. The results rejected the null hypothesis. It was found that the maquis top soil had the highest C concentration than both types of vineyards and the organic vineyard had significantly higher C concentration than the conventional one. The organic soil N followed the same pattern. The vine leaves (blades) in the conventional vineyards had significantly higher concentrations of Ca, Mg, Mn, and Zn. The average values of Mg and Zn concentrations in leaves in the organic vineyards were below the suggested ranges for nutrient sufficiency in vines and for this reason a foliar application of Mg and Zn is recommended for the organic vineyards. The average berry yield was significantly higher in the conventional vineyards.  相似文献   

10.
Summary Root and stem nodulation, nitrogen fixation (acetylene-reducing activity), growth and N accumulation bySesbania rostrata as affected by season and inoculation were studied in a pot experiment. The effects ofS. rostrata as a green manure on succeeding wet-season and dry-season rice yields and total N balance were also studied.S. rostrata grown during the wet season showed better growth, nodulation, and greater acetylene-reducing activity than that grown during the dry season. Inoculation withAzorhizobium caulinodans ORS 571 StrSpc® (resistant to streptomycin and spectinomycin) on the stem alone or on both root and stem significantly increased N2 fixation by the plants. Soil and seed inoculation yielded active root nodules under flooded conditions. Plants that were not inoculated on the stem did not develop stem nodules. The nitrogenase activity of the root nodules was greater than that of the stem nodules in about 50-day-oldS. rostrata. S. rostrata incorporation, irrespective of inoculation, significantly increased the grain yield and N uptake of the succeeding wet season and dry season rice crops. The inoculated treatments produced a significantly greater N gain (873 mg N pot–1) than the noinoculation (712 mg N pot–1) treatment. About 80% of the N gained was transferred to the succeeding rice crops and about 20% remained in the soil. The soil N in the flooded fallow-rice treatment significantly declined (–140 mg N pot–1) but significantly increased in bothS. rostrata-rice treatments (159 and 151 mg N pot–1 in uninoculated and inoculated treatments respectively). The N-balance data gave extrapolated values of N2 fixed per hectare at about 303 kg N ha–1 per two crops forS. rostrata (uninoculated)-rice and 383 forS. rostrata (inoculated)-rice.  相似文献   

11.
Many crop wild relatives are usually widely distributed species, and in this relation a question arises about selecting populations of special importance for conservation. Using Rubus idaeus as an example, we propose a compound selection of wild populations for in situ conservation. Twelve raspberry populations in the Leningrad region have been evaluated from the point of view of their significance for in situ conservation. To exclude the run-wild forms from the evaluation process, we tried to identify them applying a mathematical model developed by statusmetry method. The constructed model is based on morphological features of leaves of primocanes and helps to distinguish the wild forms from the cultivated and run-wild ones. The wild raspberry populations were screened for plants with features useful for cultivated raspberry improvement such as waxy cover presence, yellow fruiting plants, spinelessness, fruiting primocanes and others. The diversity of wild raspberry populations was assessed by variation of morphological features, presence of botanical varieties and polymorphism of seed storage proteins. The results of viability status assessment for the chosen populations reflect the perspectives of their development and permit to determine the strategy and measures for optimal conservation.  相似文献   

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