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991.
Masamichi Takahashi Patrick S Herendeen Peter R Crane 《Journal of plant research》2001,114(4):429-434
Lauranthus futabensis , gen. et sp. nov. is assigned to the Lauraceae based on the regular trimerous organization of the perianth and androecium,
and the valvate anthers. It provides the first detailed report of lauraceous flowers from the Cretaceous of Asia and adds
significantly to our knowledge of the geographic distribution of Cretaceous Lauraceae and their systematic and structural
diversity.
Received 11 April 2001/ Accepted in revised form 30 August 2001 相似文献
992.
Polyploidy is a common mode of speciation that can have far‐reaching consequences for plant ecology and evolution. Because polyploidy can induce an array of phenotypic changes, there can be cascading effects on interactions with other species. These interactions, in turn, can have reciprocal effects on polyploid plants, potentially impacting their establishment and persistence. Although there is a wealth of information on the genetic and phenotypic effects of polyploidy, the study of species interactions in polyploid plants remains a comparatively young field. Here we reviewed the available evidence for how polyploidy may impact many types of species interactions that range from mutualism to antagonism. Specifically, we focused on three main questions: (1) Does polyploidy directly cause the formation of novel interactions not experienced by diploids, or does it create an opportunity for natural selection to then form novel interactions? (2) Does polyploidy cause consistent, predictable changes in species interactions vs. the evolution of idiosyncratic differences? (3) Does polyploidy lead to greater evolvability in species interactions? From the scarce evidence available, we found that novel interactions are rare but that polyploidy can induce changes in pollinator, herbivore, and pathogen interactions. Although further tests are needed, it is likely that selection following whole‐genome duplication is important in all types of species interaction and that there are circumstances in which polyploidy can enhance the evolvability of interactions with other species. 相似文献
993.
Data about the bionomics of the pollen wasp Ceramius palaestinensis (Giordani Soika, 1957) are presented for the first time. Ceramius palaestinensis is characterized by the following ethological elements: (i) the nest is excavated in non-friable soil; (ii) the burrow is surmounted by a turret from earth extracted from within the burrow; (iii) the nest is possibly perennial; (iv) the nest has a relatively short, vertical to sub-vertical main shaft with an expansion at the bottom; (v) the main shaft is not terminated by a cell; (vi) secondary shafts are absent; (vii) the cells are sub-horizontal, all at different depths; (viii) brood cells are constructed mud-cells built within an excavated cell, formed from earth excavated within the burrow; (ix) imagines visit only flowers of Trifolium (Fabaceae) and brood cells are provisioned exclusively with pollen from this plant genus; Trifolium species varying considerably in inflorescence morphology lead to different positions of foraging wasps on the inflorescences during flower visits; Trifolium resupinatum or T. clusii inflorescences with resupinate flowers function as a disc-shaped pseudanthium with the vexilla of the flowers arranged on the outer periphery serving as petal-like exhibition organs; and (x) males patrol and perch at water collection sites, at flowers and within nesting aggregations; copulations or copulatory attempts are observed there. 相似文献
994.
The response of adult flower thrips Frankliniella intonsa (Trybom) (Thysanoptera: Thripidae) to conspecifics is investigated in Y‐tube olfactometer bioassays. The results show that both males and females are attracted to the odours of adult males, which indicates a male‐produced aggregation pheromone in this species. Gas chromatography‐mass spectroscopy analyses of headspace volatiles collected on solid‐phase microextraction fibres show that two major components and six minor components are present in volatiles from males but not in females. Further gas chromatography‐mass spectroscopy analyses reveal that the two major components in head‐space volatiles produced by F. intonsa males are the same compounds that are reported in volatiles of Frankliniella occidentalis males: (R)‐lavandulyl acetate and neryl (S)‐2‐methylbutanoate. However, the quantity of these two compounds in the volatiles differs between the species. 相似文献
995.
Abstract Canopy crane‐based studies have been carried out to quantify the sets of arthropods that visit the flowers of a suite of common species of trees, palms and vines within the Cape Tribulation study area. Those Orders that increase significantly in abundance between the budding and flowering stages of inflorescences are identified, and multivariate and univariate comparisons have been made first, among coflowering plant species and second, at different seasons for the same plant species. The analysis has been repeated for both the profile of higher arthropod taxa in the samples and for the relative abundances of families of Coleoptera: one of the Orders most frequently suggested as critical in the pollination biology of Australian rainforests. In all cases significant differences are identified among species confirming that the visitor profile is a plant species‐specific phenomenon. Profiles within plant species at different times also differed. At the ordinal level significant differences in visitor profiles associated with coflowering plants, were observed, variously, in Thysanoptera, Diptera, Lepidoptera, Coleoptera and Hymenoptera. Within the Coleoptera significant differences occurred in relative abundances of Scarabaeidae, Phalacridae, Latridiidae and Curculionidae. Seasonal differences in visitation to Syzygium gustavioides, Normanbya normanbyi and Calamus radicalis, reflected differences in Diptera, Lepidoptera, Homoptera, Thysanoptera, Hymenoptera and Araneida. Within the Coleoptera, the Elateridae and Curculionidae varied significantly between occasions. The various forms of flower/arthropod interaction that may be represented in these results are discussed, as are the implications for pollination. 相似文献
996.
Ginette Garello Claudine Ménard Blanche Dansereau Marie-Thérèse Le Page-Degivry 《Plant Growth Regulation》1995,16(2):135-139
The aim of this work was to study the impact of light applied during preharvest culture on the subsequent senescence of cut rose flower and to analyse the possible involvement of abscisic acid (ABA). The longevity of cut rose flowers was longer when rose plants were previously grown under high pressure sodium lamps than under metal halide lamps. A change in light source did not lead to a change in leaf ABA content but significantly affected the petal ABA content. The relationship between ABA level and flower longevity, previously reported for differences of genetic origin, was again observed for culture-induced differences: the higher the ABA level at harvest, the shorter the vase-life observed. 相似文献
997.
Abstract Animal‐pollinated plant species modulate the presentation of pollinator rewards to maximize reproductive success. In plants providing pollen as the only reward for pollinators, it is usually difficult to unravel the dual roles of reward presentation and the realization of male and female functions (pollen removal and deposition). Exploiting the two types of anther in the androecia of Melastoma malabathricum L., we examined whether the removal of pollen for reward is regulated primarily to favor male function or female function. Pollen removal by carpenter bees from the feeding and pollination anthers, as well as pollen deposition on the stigmas, were quantified during anthesis of M. malabathricum. There was no significant difference in pollen removal rates from the feeding and pollination anthers of M. malabathricum between the onset of anthesis and flower wilting. The stigmatic pollen loads exceeded the ovule number after three sonication bouts, and female function was satisfied earlier than male function. The results support the hypothesis that the presentation of pollination reward in this species is regulated primarily to favor the expression of male function, rather than female function, in agreement with the pollen‐donation hypothesis. A cooperative relationship between the feeding and pollination anthers was demonstrated in heterantherous flowers, which optimizes the balance in investments between pollinator rewards and “functional pollen” for gene transfer. 相似文献
998.
999.
We investigated the longevity of individual flowers of Corydalis ambigua Cham. et Schlecht. during different periods of pollinator activity and at different temperatures. To measure potential (unpollinated) flower longevity of C. ambigua, this study was conducted at forest islands where pollinator visits were scarce. The longevity of individual flowers of C. ambigua indicated high plasticity. The longevity of unpollinated flowers in natural pollination ranged from 2 to 25 days and continuously decreased with the date of flower opening. The temperature increased as the flowering season progressed. Furthermore, the greenhouse transplanting experiment showed that higher temperatures shorten the life span of flowers. The longevity of pollinated flowers subjected to hand pollination of newly opened flowers was shorter than that of unpollinated flowers in natural pollination regardless of the date of flower opening. These results showed that not only high temperature but also pollination shortens flower longevity. We discuss the role of plasticity in flower longevity for C. ambigua in relation to pollination success and reduction in the maintenance cost of the flowers. 相似文献
1000.
- Holoparasitic plants are interesting heterotrophic angiosperms. However, carrion‐ or faeces‐mimicking is rarely described for such plants. There is no information on the pollination biology of Cynomoriaceae, despite the fact that these plants are rare and vulnerable. This is the first study to reveal pollination in a member of this family, Cynomorium songaricum, a root holoparasite with a distinctive and putrid floral odour.
- From 2016 to 2018, we studied the floral volatiles, floral visitors and pollinators, behavioural responses of visitors to floral volatiles, breeding system, flowering phenology and floral biology of two wild populations of C. songaricum in Alxa, Inner Mongolia, China.
- A total of 42 volatiles were identified in inflorescences of C. songaricum. Among these volatiles are compounds known as typical carrion scents, such as p‐cresol, indole, dimethyl disulphide and 1‐octen‐3‐ol. C. songaricum is pollinated by various Diptera, such as Musca domestica, M. stabulans (Muscidae), Delia setigera, D. platura (Anthomyiidae), Lucilia sericata, L. caesar (Calliphoridae), Wohlfahrtia indigens, Sarcophaga noverca, S. crassipalpis and Sarcophila meridionalis (Sarcophagidae). The inflorescence scent of C. songaricum attracted these pollinators. The plants significantly benefit from insect pollination, although wind can be a pollen vector in the absence of pollinators. C. songaricum is a cross‐pollinated, self‐incompatible plant.
- Our findings suggest that C. songaricum releases malodorous volatiles to attract Diptera to achieve pollination. This new example lays the foundation for further comparative studies in other members of this plant group and contributes to a better understanding of fly‐pollinated, carrion mimicking plants.