共查询到20条相似文献,搜索用时 31 毫秒
1.
Use of ri-mediated transformation for production of transgenic plants 总被引:12,自引:0,他引:12
Mary C. Christey 《In vitro cellular & developmental biology. Plant》2001,37(6):687-700
Summary
Agrobacterium rhizogenes-mediated transformation has been used to obtain transgenic plants in 89 different taxa, representing 79 species from 55 genera
and 27 families. A diverse range of dicotyledonous plant families is represented, including one Gymnosperm family. In addition
to the Ri plasmid, over half these plants have been transformed with foreign genes, including agronomically useful traits.
Plants regenerated from hairy roots often show altered plant morphology such as dwarfing, increased rooting, altered flowering,
wrinkled leaves and/or increased branching due to rol gene expression. These altered phenotypic features can have potential applications for plant improvement especially in the
horticultural industry where such morphological alterations may be desirable. Use of A. rhizogenes and rol gene transformation has tremendous potential for genetic manipulation of plants and has been of particular benefit for improvement
of ornamental and woody plants. 相似文献
2.
Annalisa Giovannini Michela Zottini Giacomo Morreale Angelo Spena Andrea Allavena 《In vitro cellular & developmental biology. Plant》1999,35(1):70-75
Summary Transgenic plants of Osteospermum ecklonis were produced by cocultivation of leaf fragments with Agrobacterium tumefaciens harboring rol genes from A. rhizogenes. The phenotypic alterations caused by the different transgenes were evaluated in field trials. The genetic manipulation produced
transgenic plants characterized by the following features: 1) increased number of flowers (e.g., 35SrolC and rolABC); 2) early flowering (e.g., 35SrolC); 3) change of plant growth habit: erect (rolAB, rolABC and 35SrolC) with an increased number of branches (e.g., rolABC). The color of leaves was pale green in 35SrolC and dark green in rolAB transgenic plants. In conclusion this work reports: 1) genetic engineering of the ornamental species O. ecklonis, 2) modification of the main ornamental traits of this species by rol genes, and 3) segregation of the transgenes in the progeny. 相似文献
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Expression of Arabidopsis APETALA1 in tomato reduces its vegetative cycle without affecting plant production 总被引:2,自引:0,他引:2
Ellul Philippe Angosto Trinidad García-Sogo Begoña García-Hurtado Noemí Martín-Trillo Mar Salinas María Moreno Vicente Lozano Rafael Martínez-Zapater José M. 《Molecular breeding : new strategies in plant improvement》2004,13(2):155-163
Important agronomic traits such as fruit quality, harvesting efficiency or production largely depend on flowering time. We have analysed the effect of the overexpression of the Arabidopsis APETALA1 MADS-box gene on vegetative and reproductive growth of tomato. Constitutive expression of APETALA1 in tomato plants has major effects on the length of their growth cycle as well as on their growth habit. Transgenic tomato plants initiated flowering after the production of 6 vegetative nodes as compared to 11 nodes for the wild type plants. Most of tomato 35S:AP1 plants also showed determinate growth habit, similar to the phenotype of self pruning tomato mutants, as well as an initial reduction of their axillary growth. Moreover, development and fertility of flowers were not affected in plants expressing AP1. Consequently, fruit formation in transgenic plants grown under greenhouse conditions occurred normally, which permitted a similar fruit yield compared to control plants. Since traits conferred by AP1 expression are dominant, its expression in tomato breeding lines could provide advantages for the development of new hybrid varieties with shorter generation time, determinate growth, and reduced pruning requirements. 相似文献
5.
Development of a transgenic early flowering pear (Pyrus communis L.) genotype by RNAi silencing of PcTFL1-1 and PcTFL1-2 总被引:1,自引:0,他引:1
Freiman A Shlizerman L Golobovitch S Yablovitz Z Korchinsky R Cohen Y Samach A Chevreau E Le Roux PM Patocchi A Flaishman MA 《Planta》2012,235(6):1239-1251
Trees require a long maturation period, known as juvenile phase, before they can reproduce, complicating their genetic improvement as compared to annual plants. 'Spadona', one of the most important European pear (Pyrus communis L.) cultivars grown in Israel, has a very long juvenile period, up to 14?years, making breeding programs extremely slow. Progress in understanding the molecular basis of the transition to flowering has revealed genes that accelerate reproductive development when ectopically expressed in transgenic plants. A transgenic line of 'Spadona', named Early Flowering-Spadona (EF-Spa), was produced using a MdTFL1 RNAi cassette targeting the native pear genes PcTFL1-1 and PcTFL1-2. The transgenic line had three T-DNA insertions, one assigned to chromosome 2 and two to chromosome 14 PcTFL1-1 and PcTFL1-2 were completely silenced, and EF-Spa displayed an early flowering phenotype: flowers developed already in tissue culture and on most rooted plants 1-8?months after transfer to the greenhouse. EF-Spa developed solitary flowers from apical or lateral buds, reducing vegetative growth vigor. Pollination of EF-Spa trees generated normal-shaped fruits with viable F1 seeds. The greenhouse-grown transgenic F1 seedlings formed shoots and produced flowers 1-33?months after germination. Sequence analyses, of the non-transgenic F1 seedlings, demonstrated that this approach can be used to recover seedlings that have no trace of the T-DNA. Thus, the early flowering transgenic line EF-Spa obtained by PcTFL1 silencing provides an interesting tool to accelerate pear breeding. 相似文献
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据调查,华南地区常用园林植物在冬季开花的有48科100余种(含部分品种和变种)。根据其生物学与生态学特性可划分为冬季开花、早春开花、四季开花、热带引种、人工育成新品种或促成栽培等五大类型。在园林上可作年宵花卉、行道树或景观树、地被植物以及切花等用途。 相似文献
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B García-Sogo B Pineda EM Roque T Antón A Atarés M Borja JP Beltrán V Moreno LA Canas 《BMC plant biology》2012,12(1):156
ABSTRACT: BACKGROUND: Pelargonium is one of the most popular garden plants in the world. Moreover, it has a considerable economic importance in the ornamental plant market. Conventional cross-breeding strategies have generated a range of cultivars with excellent traits. However, gene transfer via Agrobacterium tumefaciens could be a helpful tool to further improve Pelargonium by enabling the introduction of new genes/traits. We report a simple and reliable protocol for the genetic transformation of Pelargonium spp. and the production of engineered long-life and male sterile Pelargonium zonale plants, using the pSAG12::ipt and PsEND1::barnase chimaeric genes respectively. RESULTS: The pSAG12::ipt transgenic plants showed delayed leaf senescence, increased branching and reduced internodal length, as compared to control plants. Leaves and flowers of the pSAG12::ipt plants were reduced in size and displayed a more intense coloration. In the transgenic lines carrying the PsEND1::barnase construct no pollen grains were observed in the modified anther structures, which developed instead of normal anthers. The locules of sterile anthers collapsed 3--4 days prior to floral anthesis and, in most cases, the undeveloped anther tissues underwent necrosis. CONCLUSION: The chimaeric construct pSAG12::ipt can be useful in Pelargonium spp. to delay the senescence process and to modify plant architecture. In addition, the use of engineered male sterile plants would be especially useful to produce environmentally friendly transgenic plants carrying new traits by preventing gene flow between the genetically modified ornamentals and related plant species. These characteristics could be of interest, from a commercial point of view, both for pelargonium producers and consumers. 相似文献
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John?Chandler Laurent?Corbesier Patrick?Spielmann Josef?Dettendorfer Dietmar?Stahl Klaus?Apel Siegbert?Melzer
Floral induction is a key developmental switch in plants that leads to the production of flowers, fruits and seeds, which are of paramount importance for human life. To meet the demands of several crop harvests per year, or the growth of crop plants in regions with short vegetation times and for the production of ornamental plants, the timing of the floral transition is very important. The discovery of genes that are involved in flowering time control in model plants should allow the modulation of this developmental switch also in plants with economic value. By using a transgenic approach, we showed that a single MADS box gene accelerated flowering and seed ripening in summer rape plants. The MADSB transgene also partially substituted for the strict temperature requirements for flowering in winter rape plants. Transgenic winter rape plants expressing the MADSB transgene also produced more rigid siliques than wild type winter rape plants, and this prevented precocious seed dispersal. 相似文献
10.
Transgenic tobacco (Nicotiana tabacum L, cv. SR-1) expressing mannitol 1-phosphate dehydrogenase, MTLD, in chloroplasts and myo-inositol O-methyltransferase, IMT1, in the cytosol after crossing of lines which expressed these foreign genes separately has been analysed. Plants expressing both enzymes accumulated mannitol and D-ononitol in amounts comparable to those following single gene transfer and showed phenotypically normal growth during the vegetative stage. Induction of flowering for transgenovar and wild-type occurred at the same time, but during flowering the phenotype of the transformed plants changed. Compared to wild-type, transgenic plants were characterized by curled, smaller upper leaves and elongated stems during flowering; incomplete development of flower buds with shorter sepals and pedicels resulted in increased abortion. Flowers completing development were normal. The vegetative biomass of the transformed plants was slightly higher than that of wild-type. Concentrations of soluble sugars and potassium were lower than in wild-type only in the apical parts of the transgenic plants. Both enzymes, under control of the CaMV 35S promoter, promoted accumulation of mannitol and D-ononitol in the youngest leaves close to the vegetative meristem and in flowers, suggesting that their presence could signal lower sink demand leading to a decrease in carbon import to flowers and developing seed capsules. The interpretation here is that increases of inert carbohydrates in developing sinks interfere with metabolism, such as respiration or glycolysis. This interference may be less significant in source tissues during vegetative growth than in sink tissues during seed development. 相似文献
11.
POLLINATOR-MEDIATED SELECTION ON FLORAL DISPLAY AND FLOWERING TIME IN THE PERENNIAL HERB ARABIDOPSIS LYRATA 总被引:2,自引:0,他引:2
Saskia Sandring Jon Ågren 《Evolution; international journal of organic evolution》2009,63(5):1292-1300
The evolution of floral display and flowering time in animal-pollinated plants is commonly attributed to pollinator-mediated selection. Yet, the causes of selection on flowering phenology and traits contributing to floral display have rarely been tested experimentally in natural populations. We quantified phenotypic selection on morphological and phenological characters in the perennial, outcrossing herb Arabidopsis lyrata in two years using female reproductive success as a proxy of fitness. To determine whether selection on floral display and flowering phenology can be attributed to interactions with pollinators, selection was quantified both for open-pollinated controls and for plants receiving supplemental hand-pollination. We documented directional selection for many flowers, large petals, late start of flowering, and early end of flowering. Seed output was pollen-limited in both years and supplemental hand-pollination reduced the magnitude of selection on number of flowers, and reversed the direction of selection on end of flowering. The results demonstrate that interactions with pollinators may affect the strength of selection on floral display and the direction of selection on phenology of flowering in natural plant populations. They thus support the contention that pollinators can drive the evolution of both floral display and flowering time. 相似文献
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Plant transformation technology (hereafter abbreviated to GM, or genetic modification) has been used to develop many varieties of crop plants, but only a few varieties of ornamental plants. This disparity in the rate and extent of commercialisation, which has been noted for more than a decade, is not because there are no useful traits that can be engineered into ornamentals, is not due to market potential and is not due to a lack of research and development activity. The GM ornamental varieties which have been released commercially have been accepted in the marketplace. In this article, progress in the development of transgenic ornamentals is reviewed and traits useful to both consumers and producers are identified. In considering possible factors limiting the release of genetically modified ornamental products it is concluded that the most significant barrier to market is the difficulty of managing, and the high cost of obtaining, regulatory approval. 相似文献
14.
Outcrossing and sexual reproduction of most flowering plants depends on pollinators. Plant traits likely to be involved in pollinator attraction include flower color, shape, and size. Furthermore, plant or flower density and the temporal flowering pattern may have an effect on reproduction. In this study, we examine the pollination ecology, breeding system, female reproductive output, and germination of two tropical understory species, Stenostephanus lobeliiformis (Acanthaceae) and Besleria melancholica (Gesneriaceae), which differ in these traits. Pollinator observations revealed that the dense flowering S. lobeliiformis with pinkish flowers received a higher diversity of pollinators, but visitor frequency measured as visits per flower per hour was much less (0.1 h?1) than that to B. melancholica, which has a smaller floral display of dull-colored flowers (1.5 h?1). Pollination experiments revealed that S. lobeliiformis but not B. melancholica is pollen-limited. In addition, both species are partially self-incompatible and depend on pollinators for outcrossing. Natural fruit set of open-pollinated unmanipulated flowers (control treatment) in both species is 22–26 %. Germination studies indicated inbreeding depression in S. lobeliiformis. We conclude that the pollination ecology of these species is influenced by a broad set of traits and that very different combinations of these traits can be successful in terms of reproduction. 相似文献
15.
Pollination is a requisite for sexual reproduction in plants and its success may determine the reproductive output of individuals. Pollinator preference for some floral designs or displays that are lacking or poorly developed in focal plants may constrain the pollination process. Foliar herbivory may affect the expression of floral traits, thus reducing pollinator attraction. Natural populations of the Andean species Alstroemeria exerens (Alstromeriaceae) in central Chile show high levels of foliar herbivory, and floral traits show phenotypic variation. In the present field study, we addressed the attractive role of floral traits in A. exerens and the effect of foliar damage on them. Particularly, we posed the following questions: (1) Is there an association between floral display and design traits and the number and duration of pollinator visits? and (2) Does foliar damage affect the floral traits associated with pollinator visitation? To assess the attractiveness of floral traits for pollinators, we recorded the number and duration of visits in 101 focal plants. To evaluate the effects of foliar damage on floral traits, 100 plants of similar size were randomly assigned to control or damage groups during early bud development. Damaged plants were clipped using scissors (50% of leaf area) and control plants were manually excluded from natural herbivores (<5% of leaf area eaten). During the peak of flowering, we recorded the number of open flowers, and estimated corolla and nectar guide areas. The number and duration of pollinator visits was statistically associated with floral design and display traits. Plants with larger displays, corollas and nectar guide areas received more visits. Visits lasted longer as display increases. In addition, foliar damage affected attractive traits. Damaged plants had fewer open flowers and smaller nectar guide areas. We conclude that foliar damage affects plant attractiveness for pollinators and hence may indirectly affect plant fitness. 相似文献
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Climate change may disrupt plant–pollinator mutualisms by generating phenological asynchronies and by altering traits that shape interaction costs and benefits. Our knowledge is limited to studies that manipulate only one partner or focus on either phenological or trait-based mismatches. We assembled communities of three annual plants and a solitary bee prior to flowering and emergence to test how springtime warming affects phenologies, traits, interactions and reproductive output. Warming advanced community-level flowering onset, peak and end but did not alter bee emergence. Warmed plant communities produced fewer and smaller flowers with less, more-concentrated nectar, reducing attractiveness, and warmed bees were more generalized in their foraging, reducing their effectiveness. Plant–bee interactions were less frequent, shorter and peaked earlier under warming. As a result, warmed plants produced fewer, lighter seeds, indicating pollinator-mediated fitness costs. Climate change will perturb plant–pollinator mutualisms, causing wide-ranging effects on partner species and diminishing the ecosystem service they provide. 相似文献
18.
A test of the effect of floral color change on pollination effectiveness using artificial inflorescences visited by bumblebees 总被引:2,自引:0,他引:2
Floral color change has been recognized as a pollination strategy, but its relative effectiveness has been evaluated insufficiently
with respect to other floral traits. In this study, effects of floral color change on the visitation pattern of bumblebees
were empirically assessed using artificial flowers. Four inflorescence types were postulated as strategies of flowering behavior:
type 1 has no retention of old flowers, resulting in a small display size; type 2 retains old flowers without nectar production;
type 3 retains old flowers with nectar; and type 4 retains color-changed old flowers without nectar. Effects of these treatments
varied depending on both the total display size (single versus multiple inflorescences) and the pattern of flower-opening.
In the single inflorescence experiment, a large floral display due to the retention of old flowers (types 2–4) enhanced pollinator
attraction, and the number of flower visits per stay decreased with color change (type 4), suggesting a decrease in geitonogamous
pollination. Type-4 plants also reduced the foraging time of bees in comparison with type-2 plants. In the multiple inflorescence
experiment, the retention of old flowers did not contribute to pollinator attraction. When flowering occurred sequentially
within inflorescences, type-4 plants successfully decreased the number of visits and the foraging time in comparison with
type-2 plants. In contrast, floral color change did not influence the number of visits, and it extended the foraging time
when flowering occurred simultaneously within inflorescences but the opening of inflorescences progressed sequentially within
a plant. Therefore, the effectiveness of floral color change is highly susceptible to the display size and flowering pattern
within plants, and this may limit the versatility of the color change strategy in nature. 相似文献
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