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1.
We compared the effects of ant presence at extrafloral nectaries of Lafoensia pacari St. Hil. on herbivore damage and silicon accumulation. Plants that were accessible to ants experienced lower herbivory levels over the first 3 mo of the experiment. After 3 mo, most leaves were fully expanded with inactive extrafloral nectaries; by 6 mo there was no effect of ant access on herbivore damage. Along with experiencing higher herbivory, plants in the ant‐exclusion treatment had significantly higher silicon levels in their leaves, suggesting that silicon serves as an induced defense in this ant–plant–herbivore interaction.  相似文献   

2.
Twenty-one flavonoid glycosides were isolated from the leaves of 22 North AmericanVitis L. taxa, representing two subgenera and five series. Three chemical groups were evident: one producing flavonols, flavones, and C-glycosylflavones, a second producing flavonols and flavones, and a third producing only flavonols. These three chemical groups did not correspond to any of the subgeneric groupings based on morphology. However, flavonoid distributions within series in each subgenus correlate well with morphological data. Parallel flavonoid evolution within each series is thought to account for this lack of subgeneric and interserial flavonoid distinction. The flavonoid data indicate that seriesCordifoliae of subgenusVitis, particularlyV. vulpina L., is the most closely related group to subgenusMuscadinia (Planch.)Rehder, and represents an evolutionary link between the two subgenera.  相似文献   

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4.
A successful protocol was developed for mass propagation of Lawsonia inermis Linn., an important medicinal plant. Multiple shoots were induced in apical and axillary meristems derived from mature explants of L. inermis on Murashige and Skoog (1962) medium supplemented with 0.25 mg/l 6-benzylaminopurine (BA), 0.25 mg/l Kinetin (Kn), 0.5 mg/l ascorbic acid and 3% (w/v) sucrose. The rate of multiplication was higher when the cultures were incubated under continuous light rather than the 14 hr photoperiod. Rooting was readily achieved upon transferring the microshoots onto MS basal semi-solid medium supplemented with 0.25 mg/l indole-3-butyric acid (IBA) after ten days of culture. Micropropagated plantlets were acclimatized and successfully grown in soil.  相似文献   

5.
There is growing evidence that many self-compatible plants control the level of self-fertilization with postpollination processes that give a siring advantage to cross pollen over self pollen through "cryptic self-incompatibility" (CSI). Previous marker-gene experiments with self-compatible, tristylous Decodon verticillatus (Lythraceae) have demonstrated a siring advantage to cross pollen, though the extent to which this advantage results from prezygotic discrimination vs. early acting inbreeding depression is not clear. Here, we provide evidence that prezygotic mechanisms are involved in this siring advantage by comparing pollen tube numbers at various times following cross- and self-pollination conducted in a natural population. In the 24 h following pollination, cross pollen yielded almost twice as many pollen tubes at various positions in the style compared to self pollen. After 36 and 48 h, the difference between pollen types had disappeared, suggesting that the advantage to cross pollen results from differences in the rate of pollen germination and;clor tube growth rather than pollen tube attrition. Comparison of tube numbers after legitimate vs. illegitimate cross-pollination did not reveal any difference, suggesting that D. verticillatus possesses CSI unrelated to heteromorphic self- and intramorph-incompatibility found in other heterostylous members of the Lythraceae. CSI resulting from differential pollen tube growth may minimize geitonogamous selfing when cross pollen is abundant, while maximizing fecundity when cross pollen is scarce due to local clonal spread.  相似文献   

6.
Five new species are described, three of which, C. crassiflora, C. paucipetala, and C. trochilus, belong to sect. Heterodon, a group of predominantly annual, western Mexican species. The perennial C. rasilis is a new member of sect. Melvilla and the perennial C. spectabilis is new to sect. Diploptychia. Chromosome numbers for the annual species and two additional ones, C. procumbens and C. koehneana, closely related to the novelties, are reported for the first time.  相似文献   

7.
Cuphea luteola is described from cerrado vegetation in Noel Kempff Mercado National Park, eastern Bolivia. It is assigned to sectionEuandra subsectionOidemation and is distinguished by yellow flowers, linear uninerved leaves, and the inner surface of the floral tube pilose and without vesicles. Several species of the subsection share one or more characters withC. luteola, but none are closely similar.  相似文献   

8.
Described as new areCuphea flavovirens (sect.Heterodon), C. dibrachiata (sect.Leptocalyx), andC. ownbeyi (sect.Diploptychia).  相似文献   

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Tetrataxis, a monotypic endemic of Mauritius, has been known since the 1790s only by the type collection in the Paris Herbarium. Now a colony of seven individuals has been discovered in a valley south-east of the type area. The small trees grow in saturated soil in a low open wet forest. Vegetatively, they resemble the more common Syzygium or Eugenia. Characteristics of the pollen and seed, anatomy of stems and leaves, and an approximate chromosome number are reported for the first time. A lectotype is selected from material of the original collection. Tetrataxis displays a number of advanced characters. It appears to have no close affinity to any single member of the family.  相似文献   

11.
Foliar flavonoids of 31 species of the Annonaceae native to Brazil, amounting to 76 compounds, were isolated and identified. All phenols found were glycosides of either flavones (apigenin, scutellarein, hispidulin and luteolin) or flavonols (kaempferol, rhamnocitrin, 6-hydroxyrhamnocitrin, quercetin, isorhamnetin and rhamnetin), with the latter predominating. Some members of the tribe Bocageeae are distinctive for accumulating 6-oxygenated flavones and flavonols, in addition to 7-O-methylated flavonols, a feature possibly linked to the assumed advanced condition of the tribe within the family. Members of Duguetia stand out for the apparent absence of quercetin glycosides. Anaxagorea dolichocharpa seemingly lacks flavones and flavonols entirely. A UPGMA analysis based on the distribution of flavonoids does not group the analyzed species according to the available tribal division of the Annonaceae. However, several taxonomically meaningful groupings emerged through the multivariate analysis.  相似文献   

12.
Nesaea petrensis sp. nov., from seepage areas on granitic outcrops in the Bay Region of southern Somalia, is described and illustrated.  相似文献   

13.
New microsatellite loci for pomegranate, Punica granatum (Lythraceae)   总被引:1,自引:0,他引:1  
? Premise of the study: A new set of pomegranate microsatellites was selected and characterized to assess the level of genetic diversity among cultivars and wild genotypes. ? Methods and Results: Nine Simple Sequence Repeat (SSR) markers were obtained using the Microsatellite-AFLP technique and were successfully amplified in 34 genotypes belonging to Italian, Spanish, and Turkish germplasm collections. The number of alleles per locus ranged from 1 to 5, and the total number of alleles was 22. ? Conclusions: Because only a few codominant markers are available for this species, the newly identified SSRs will facilitate genetic diversity studies, fingerprinting, and mapping. In addition, the 9 loci successfully amplified in P. granatum var. nana. No cross transferability was observed for Cuphea micropetala and Lagerstroemia indica (Lythraceae).  相似文献   

14.
Style morph frequencies (shortmidlong) were determined for a total of n = 11 918 plants in 16 Minnesota populations of Lythrum salicaria L. Nine populations were in the establishment phase, with population sizes ranging from n = 56 to n = 2 192. Most of these populations exceeded previously reported population sizes in the native European habitat. A nonparametric statistical test, the chi-square (2), can be used to determine if populations are at isoplethic equilibrium (111, shortmidlong); a 2 value >5.99 is significant at the 5% level. Only one established population (White Bear Lake, n = 1991, 2 = 3.0) fitted the null hypothesis for isoplethy, although all established populations contained all three style morphs. Pooled values for these populations indicated an excess of mids and longs, with shorts being deficient. Colonizing populations had a higher percentage of mids (54%) when compared to established populations (33.7%). Short styles were almost nonexistent (8%) in colonizing populations. Five out of the seven populations lacked at least one style morph. A review of the literature reporting style morph frequencies in tristylous L. salicaria revealed that no statistical analysis for isoplethy has been performed. Darwin originally assumed that all populations would be isoplethic, possessing equal numbers of all three style morphs, but concluded, without statistical analysis, that, instead, populations were anisoplethic. Since tests for statistical deviations from the expected frequencies (111) have not been used, 2 analysis was performed. Several of these populations were at isoplethic equilibrium (Nadder su2 = 1.7, Blelham 2 = 1.69, Potsdam 2 = 1.5, Vestfold 2 = 0.4, Buskerud 2 = 5.62, Kilchberg 2 = 0.35, Lausanne 2 = 3.32, Canberra 2 = 5.29, Massachusetts 2 = 3.13), suggesting that the general conclusion of anisoplethy in tristylous L. salicaria is inappropriate.This is Scientific Journal Series Paper Number 19 128 of the Minnesota Agricultural Experiment Station  相似文献   

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A new species, Rotala pseudojuniperina, is described and illustrated. It grows in a seasonal pond on a high altitude lateritic plateau ecosystem of the northern Western Ghats, India. It resembles the African species R. juniperina in having trimerous flowers, but differs in longer sepal appendages, ovoid capsule and ellipsoid seeds. Amongst the Indian species, R. pseudojuniperina shows affinities towards R. densiflora but differs in trimerous flowers, ovoid capsule and longer and ellipsoid seeds.  相似文献   

17.
Heterostyly typically involves reciprocal polymorphism in stamen and style lengths, physiological self- and intramorph-incompatibility, and a set of associated polymorphisms of pollen and stigma characters. This study examined floral morphology and compatibility relationships in the monotypic, herbaceous perennial Decodon verticillatus (Lythraceae). There have been conflicting reports on the occurrence of tristyly in the species, probably because of frequent loss of style morphsm from populations in parts of the species' range. Floral morphology was examined using material collected from natural populations throughout the range. Detailed floral measurements revealed discrete trimorphism in style length and anther positioning in three populations. Data from two dimorphic populations showed similar patterns of floral polymorphism, except that both were missing the mid-styled morph. In one dimorphic population, there was evidence for modification in the length of mid-level stamens. Measurements in three populations indicated pronounced floral variability, including high frequencies of modified phenotypes with reduced stigma-anther separation. Pollen size was only weakly differentiated among anther levels, and there were no differences in pollen production among anther levels or morphs. In contrast, stigma size and papilla length showed a strong negative correlation with style length; a pattern opposite to most heterostylous species. Experimental crosses performed under glasshouse conditions on plants from two populations showed a high degree of both self- and intramorph-compatibility. A comparative analysis of floral morphology showed that D. verticillatus is not unusual in terms of the precision and reciprocity of organ positioning compared with 13 other tristylous species.  相似文献   

18.
A total of 19 compounds were isolated from the leaves of five North American members of the genus Vitis The flavonoid data indicate three distinct chemical groups: one producing flavonols, flavones and C-glycosylflavones (V. aestivalis and V. cinerea var. cinerea, one producing fiavonols and flavones (V. cinerea ver. floridana) and one producing only fiavonols ( V. vulpina and V. riparia). The fiavonoid complements of the taxa are extremely useful in taxon delimitation and in suggesting systematic relationships.  相似文献   

19.
A phylogenetic analysis of the New World genus Cuphea was conducted employing sequences from the nuclear rDNA internal transcribed spacer (ITS) and chloroplast trnL-trnF spacer and rpl16 intron. The analysis expands the number of Cuphea species from 53 in an earlier ITS study to 70 and adds two chloroplast data sets in order to generate a more complete and robust phylogeny and to test a previous result that suggested the presence of a large North American clade. Results reaffirm the monophyly of Cuphea with Pleurophora as the sister genus and recover a basal divergence event that mirrors the two subgenera of the current classification. Phylogenies of the two chloroplast regions are largely unresolved beyond the initial dichotomy and some resolution at the terminal and subterminal nodes. Based on the ITS phylogeny, five major clades are recognized. Subgenus Cuphea (Clade 1), defined morphologically by the synapomorphic loss of bracteoles, is sister to the much larger subg. Bracteolatae (Clades 2–5). Clades 2–4, comprising the South American and Caribbean species, grade successively to Clade 5, an exclusively North American lineage of 29 species. Among the 12 sections included in the study, only section Trispermum, a subclade of Clade 4, is monophyletic. Section Pseudocircaea is nested within Clade 3, which is largely equivalent to section Euandra. The North American endemic clade includes four sections, of which none are recovered as monophyletic in this study.  相似文献   

20.
A total of ten flavonoids, all flavonols, were isolated from leaves of eleven species of Solanum sect. Solanum. Most species had relatively few compounds, primarily quercetin 3-O-glycosides. Little intraspecific variation in flavonoids was observed, except in S. americanum were it correlated with previously recognized races. Flavonoid data are of little help in determining ancestries of polyploid species, but do rule out S. sarrachoides as a progenitor of S. villosum and S. nigrum. Solanum sarrachoides is unique among species examined in having free flavonoid aglycones as well as extensive 3-O-methoxylation.  相似文献   

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