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1.
Stearidonic acid (18:4ω3), which is reported to be of rare occurrence in the plant kingdom and which is of considerable dietary and pharmaceutical interest has been found in three closely related Primula species. It occurs, together with γ-linolenic acid (3–4% of the seed oil total fatty acids), in significant percentages in Primula florindae (11%), P. sikkimensis (14%) and P. alpicola (14%). 18:4(ω3 may also be of chemotaxonomic interest in the genus Primula, as high levels may be typical for section Sikkimensis. The only commercial plant source of stearidonic acid known so far is the seed oil of Ribes nigrum. 相似文献
2.
Viqar Uddin Ahmad Mohammad Ghani Shah Faryal Vali Mohammad Nargis Ismail Mushtaq Noorwala 《Phytochemistry》1991,30(12)
A new flavone glucoside macrophylloside has been isolated from the whole plant of Primula macrophylla and its structure was determined by spectroscopic methods as 2′-hydroxy-7-O-β-
-glucopyranosyloxyflavone. Sitosterol glucoside was also isolated for the first time from this plant. 相似文献
3.
Summary The stigmatic dimorphisms in the distylous speciesPrimula obconica, which has been dealt with in an earlier paper, has been described further. An ultrastructural localization of various enzymes in the exudates is hereby revealed, and evidence is given for intermorph differences. Esterases are confined to the lipid phase of the exudates, including the lipid globuli in the papillae walls of both morphs, but they are not found in the pellicle of the dry thrum stigma. However, this pellicle exhibits acid phosphatase activity, as does the lumen of the blisters in the viscous exudate on pin stigmas. The blisters are presumed to hold the watery phase of the pin secretion. From the present findings and from previous results with LM cytochemical methods it is suggested that the sites of peroxidase activity resemble those of acid phophatases. 相似文献
4.
A smut fungus onPrimula sieboldii was newly found in Japan and identified asUrocystis tranzscheliana by comparative morphology. This species causes systemic infection ofP. sieboldii and produces sori in its ovaries.Contribution No. 121, Laboratories of Plant Pathology and Mycology, Institute of Agriculture and Forestry, University of Tsukuba. 相似文献
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Primarily, 50 characters taken from herbarium specimens, cultivated plants, and whole populations ofPrimula veris L. were critically evaluated. Only 24 characters were found to be suitable for taxonomic use. The geographical and multivariate analysis of about 1000 herbarium specimens from the whole area lead to a reduction of the number of subspecies. Only a less restricted subsp.veris (incl. subsp.canescens, subsp.inflata and probably including subsp.macrocalyx) and subsp.columnae (incl. subsp.suaveolens) can be distinguished considering the variability of characters within an individuum, under different culture conditions, and during the growth period. The status of the taxon macrocalyx cannot be cleared presently. 相似文献
8.
Reproductive traits that function in pollinator attraction may be reduced or lost during evolutionary transitions from outcrossing to selfing. Although floral scent plays an important role in attracting pollinators in outcrossing species, few studies have investigated associations between floral scent variation and intraspecific mating system transitions. The breakdown of distyly to homostyly represents a classic example of a shift from outcrossing to selfing and provides an opportunity to test whether floral fragrances have become reduced and/or changed in composition with increased selfing. Here, we evaluate this hypothesis by quantifying floral volatiles using gas chromatography-mass spectrometry in two distylous and four homostylous populations of Primula oreodoxa Franchet, a perennial herb from SW China. Our analysis revealed significant variation of volatile organic compounds (VOCs) among populations of P. oreodoxa. Although there was no difference in VOCs between floral morphs in distylous populations as predicted, we detected a substantial reduction in VOC emissions and the average number of scent compounds in homostylous compared with distylous populations. A total of 12 compounds, mainly monoterpenoids and sesquiterpenoids, distinguished homostylous and distylous morphs; of these, (E)-β-ocimene was the most important in contributing to the difference in volatiles, with significantly lower emissions in homostyles. Our findings support the hypothesis that the transition from outcrossing to selfing is accompanied by the loss of floral volatiles. The modification to floral fragrances in P. oreodoxa associated with mating system change might occur because high selfing rates in homostylous populations result in relaxed selection for floral attractiveness. 相似文献
9.
The evaluation of pollen quality,and a further appraisal of the fluorochromatic (FCR) test procedure
J. Heslop-Harrison Y. Heslop-Harrison K. R. Shivanna 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1984,67(4):367-375
Summary Methods currently available for evaluating pollen quality in vitro include, (a) tests of germinability; (b) tests of the stainability of the vegetative cell contents; (c) tests for enzyme activity, and (d) the fluorochromatic procedure (FCR), which tests principally the integrity of the plasmalemma of the vegetative cell. Using germinability in vitro as a standard, a comparison has been made between histochemical methods of classes (b), (c) and (d) in application to various pollens, immature, mature, and treated in ways known to affect viability and membrane state. Predictably, the lowest correlation was obtained with tests of stainability. The highest was given by the FCR, which generally provided an excellent guide to potential germinability. The FCR procedure is subject to various limitations, however, (a) A high correlation between FCR and germinability can only be expected when mature, ripe pollen is used; with immature pollen, the FCR will predict excessively high potential germinability. (b) The FCR may also predict a higher potential level of pollen function than in vitro germinability when the germination medium is sub-optimal. In this situation, however, it will generally give a better guide to fertilising capacity, (c) The FCR is not a test of pollen viability. Like germinability in vitro, it can yield a negative score with pollen which is nevertheless capable of functioning. For example, false negatives will be obtained with some species if the pollen is not properly pre-conditioned by rehydration before testing, an important point in monitoring stored pollen. The paper includes a brief discussion of the rationale of pollen testing. 相似文献
10.
现存物种的分布格局、遗传结构是当前因素和历史因素共同作用的结果。人类的过度开发、全球变暖等当前因素造成的生境片段化是目前许多报春花属植物濒危的一大原因。该文总结了近年来报春花属内的保育遗传学研究进展,期望以此为更好地保护报春花属植物提供一定的理论基础。应用亲缘地理学研究方法可以弥补古生物学难以研究报春花植物历史成因的不足,因此也总结该方法在报春花属内的研究进展,并初步整理不同地区间的报春花属植物的分化式样,同时期望这些研究成果能为为研究报春花属植物在应对全球气候变化的响应机制方面提供一些参考。 相似文献