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81.
To determine the contribution of polar auxin transport (PAT) to auxin accumulation and to adventitious root (AR) formation in the stem base of Petunia hybrida shoot tip cuttings, the level of indole-3-acetic acid (IAA) was monitored in non-treated cuttings and cuttings treated with the auxin transport blocker naphthylphthalamic acid (NPA) and was complemented with precise anatomical studies. The temporal course of carbohydrates, amino acids and activities of controlling enzymes was also investigated. Analysis of initial spatial IAA distribution in the cuttings revealed that approximately 40 and 10 % of the total IAA pool was present in the leaves and the stem base as rooting zone, respectively. A negative correlation existed between leaf size and IAA concentration. After excision of cuttings, IAA showed an early increase in the stem base with two peaks at 2 and 24 h post excision and, thereafter, a decline to low levels. This was mirrored by the expression pattern of the auxin-responsive GH3 gene. NPA treatment completely suppressed the 24-h peak of IAA and severely inhibited root formation. It also reduced activities of cell wall and vacuolar invertases in the early phase of AR formation and inhibited the rise of activities of glucose-6-phosphate dehydrogenase and phosphofructokinase during later stages. We propose a model in which spontaneous AR formation in Petunia cuttings is dependent on PAT and on the resulting 24-h peak of IAA in the rooting zone, where it induces early cellular events and also stimulates sink establishment. Subsequent root development stimulates glycolysis and the pentose phosphate pathway.  相似文献   
82.
Macrophomina phaseolina is a causal agent for charcoal rot and cause economic damage in plants. In recent years, the great tendency for the use of biological substances to control of pests, weeds and the pathogens has been created. In this study, antifungal effects of concentrations 30, 60 and 120?μl/100?ml of essential oil of Eucalyptus sp. and Zataria multiflora were evaluated on the growth of M. phaseolina in vitro condition. The experiment was conducted on phactorial basis of completely randomised design with four replications. According to the results, a significant difference between inhibitory percentage of essential oils and different concentrations of essential oils on fungal colony growth has been observed (p?≤?0.01). Highest inhibitory percentage was related to the concentration of 120?μl/100?ml of Z. multiflora with 58.16% inhibition.  相似文献   
83.
ABSTRACT: BACKGROUND: Wild food plants (WFPs) contribute to the nutrition, economy and even cultural identity of people in many parts of the world. Different factors determine the preference and use of WFPs such as abundance, availability, cultural preference, economic conditions, shortage periods or unsecure food production systems. Understanding these factors and knowing the patterns of selection, use and cultural significance and value of wild food plants for local communities is helpful in setting priorities for conservation and/or domestication of these plants. Thus in this study knowledge of wild food plant use among four groups namely Dai, Lahu, Hani and Mountain Han in Naban River Watershed National Nature Reserve ((NRWNNR), Xishuangbanna were documented and analyzed to find the similarity and difference among their plant use. METHODS: Data on wild food plant use was collected through freelisting and semi-structured interviews and participatory field collection and direct observation. Botanical plant sample specimens were collected, prepared, dried and identified. RESULTS: A total of 173 species and subspecies from 64 families and one species of lichen (Ramalina sp.) are used as WFP. There were differences on the saliency of wild food plant species among four ethnic groups. Consensus analysis revealed that knowledge of wild food plant use for each ethnic group differs from others with some variation in each group. Among informant attributes only age was related with the knowledge if wild food plant use, whereas no significant relationship was found between gender and age*gender and informants knowledge of wild food plant use. CONCLUSION: Wild food plants are still used extensively by local people in the NRWNNR, some of them on a daily base. This diversity of wild food plants provide important source of nutrients for the local communities which much of their caloric intake comes from one or few crops. The results also show the role of ethnicity on the preference and use of wild food plants. There is a big potential for harvesting, participatory domestication and marketing of WFPs especially in the tourism sector in the area.  相似文献   
84.
An adapted bioactive foamed emulsion bioreactor for the treatment of benzene vapor has been developed. In this reactor, bed clogging was resolved by bioactive foam as a substitute of packing bed for interfacial contact of liquid to gaseous phase. The pollutant solubility has been increased using biocompatible organic phase in liquid phase and this reactor can be applied for higher inlet benzene concentration. Experimental results showed a benzene elimination capacity (EC) of 220 g m−3 h−1 with removal efficiency (RE) of 85% for benzene inlet concentration of 1–1.2 g m−3 at 15 s gas residence time in bioreactor. Assessment of benzene concentration in liquid phase showed that a significant amount of transferred benzene mass has been biodegraded. By optimizing the operational parameters of bioreactor, continuous operation of bioreactor with high EC and RE was demonstrated. With respect to the results, this reactor has the potential to be applied instead of biofilter and biotrickling filters.  相似文献   
85.
Abstract. The diaspore bank (seeds of higher plants and spores of ferns and bryophytes) was assessed between 3 and 5 yr after experiments to control Pteridium aquilinum (bracken) and restore appropriate vegetation were initiated at two contrasting locations in the UK. We tested the response of the diaspore bank using univariate and multivariate analysis of variance. The two approaches were complementary and together improved the interpretation of these results. There were considerable differences in the diaspore banks of the two sites and among the experimental locations within sites. Within each experiment there were differences in species composition, with species that were (1) common to both diaspore bank and vegetation, (2) restricted to the diaspore bank and (3) restricted to the vegetation. There is a possibility of increasing the biodiversity of the developing vegetation if some of the species present in the diaspore bank can be germinated. This was especially true for ferns where four species were found in the spore bank which were not present in the vegetation. There were few significant effects of management treatment on the diaspore bank as the experiments had been in progress for only 3 to 5 yr, but a few species had different densities in the different treatments (Betula pubescens, Juncus effusus and some bryophytes). The greatest correlation between vegetation and diaspore bank was found at the top hierarchical level (entire dataset) and this progressively reduced with scale. We interpret this as a landscape/species pool effect: as the scale of the study reduces the correlation between diaspore bank and vegetation also reduces, at least over the time scale of our study. The relevance of these results for restoration ecology is discussed briefly.  相似文献   
86.
In this study, the seed oil content and fatty acid (FA) profile of 21 populations from 16 wild Salvia species of Iran were analyzed by GC. Patterns of chemical variations of the oils among species were identified via numerical analyses and also the taxonomic status of the infrageneric grouping was outlined in the genus. Salvia species were scored based on the contents of main FAs using principal coordinate analysis (PCO). The results showed that the total oil content in the seeds varied significantly, and ranged from 6.68 to 38.53% dry weight. α‐Linolenic (18:3ω3, 1.69 – 53.56%), linoleic (18:2ω6, 13.04 – 60.64%), oleic (18:1ω9, 6.15 – 27.06%), palmitic (16:0, 3.77 – 9.27%), and stearic (18:0, 1.78 – 3.05%) acid were identified as five major FAs in the oils. The amount of ω‐3 and ω‐6 FAs ranged between 1.90 – 53.80% and 13.46 – 60.83% of total FAs in the seed oils, respectively. The results confirmed that FA profiles were distinctive among the species and that they can be used as chemotaxonomic markers. The discrimination of Salvia species according to their botanical classification at intersectional level was supported. In general, seed oils of Salvia species were rich sources of polyunsaturated FAs, except in linoleic and α‐linolenic acid, and may be valuable for food and pharmaceutical industries.  相似文献   
87.
88.
A simple, rapid, precise and accurate isocratic reversed-phase stability-indicating HPLC method was developed and validated for the simultaneous determination of atorvastatin (AT) and amlodipine (AM) in commercial tablets. The method has shown adequate separation for AM, AT from their associated main impurities and their degradation products. Separation was achieved on a Perfectsil Target ODS-3, 5 microm, 250 mm x 4.6 mm i.d. column using a mobile phase consisting of acetonitrile-0.025 M NaH(2)PO(4) buffer (pH 4.5) (55:45, v/v) at a flow rate of 1 ml/min and UV detection at 237 nm. The drugs were subjected to oxidation, hydrolysis, photolysis and heat to apply stress conditions. The linearity of the proposed method was investigated in the range of 2-30 microg/ml (r=0.9994) for AT and 1-20 microg/ml (r=0.9993) for AM. The limits of detection were 0.65 microg/ml and 0.35 microg/ml for AT and AM, respectively. The limits of quantitation were 2 microg/ml and 1 microg/ml for AT and AM, respectively. Degradation products produced as a result of stress studies did not interfere with the detection of AT and AM and the assay can thus be considered stability-indicating.  相似文献   
89.
Journal of Plant Growth Regulation - This work investigated the effects of the hormonal priming of saffron corms before planting with 6-benzylaminopurine (BAP) as cytokinin, and gibberellic acid...  相似文献   
90.
Length‐weight relationships were estimated for eight species of Iranian loaches. The L‐W parameters for three of the species are given for the first time.  相似文献   
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