共查询到20条相似文献,搜索用时 31 毫秒
1.
Cristina Cvitanich Wojciech J Przybyłowicz Dorian F Urbanski Anna M Jurkiewicz Jolanta Mesjasz-Przybyłowicz Matthew W Blair Carolina Astudillo Erik Ø Jensen Jens Stougaard 《BMC plant biology》2010,10(1):26
Background
Iron is an important micronutrient for all living organisms. Almost 25% of the world population is affected by iron deficiency, a leading cause of anemia. In plants, iron deficiency leads to chlorosis and reduced yield. Both animals and plants may suffer from iron deficiency when their diet or environment lacks bioavailable iron. A sustainable way to reduce iron malnutrition in humans is to develop staple crops with increased content of bioavailable iron. Knowledge of where and how iron accumulates in seeds of crop plants will increase the understanding of plant iron metabolism and will assist in the production of staples with increased bioavailable iron. 相似文献2.
Sylvain Legrand Theo Hendriks Jean-Louis Hilbert Marie-Christine Quillet 《BMC plant biology》2007,7(1):27
Background
Somatic embryogenesis (SE) is an asexual propagation pathway requiring a somatic-to-embryonic transition of differentiated somatic cells toward embryogenic cells capable of producing embryos in a process resembling zygotic embryogenesis. In chicory, genetic variability with respect to the formation of somatic embryos was detected between plants from a population of Cichorium intybus L. landrace Koospol. Though all plants from this population were self incompatible, we managed by repeated selfing to obtain a few seeds from one highly embryogenic (E) plant, K59. Among the plants grown from these seeds, one plant, C15, was found to be non-embryogenic (NE) under our SE-inducing conditions. Being closely related, we decided to exploit the difference in SE capacity between K59 and its descendant C15 to study gene expression during the early stages of SE in chicory. 相似文献3.
Background
The plant hormone abscisic acid (ABA) is ubiquitous among land plants where it plays an important role in plant growth and development. In seeds, ABA induces embryogenesis and seed maturation as well as seed dormancy and germination. In vegetative tissues, ABA is a necessary mediator in the triggering of many of the physiological and molecular adaptive responses of the plant to adverse environmental conditions, such as desiccation, salt and cold. 相似文献4.
Background
Latest research shows that small antimicrobial peptides play a role in the innate defense system of plants. These peptides typically contribute to preformed defense by developing protective barriers around germinating seeds or between different tissue layers within plant organs. The encoding genes could also be upregulated by abiotic and biotic stimuli during active defense processes. The peptides display a broad spectrum of antimicrobial activities. Their potent anti-pathogenic characteristics have ensured that they are promising targets in the medical and agricultural biotechnology sectors. 相似文献5.
《Aquatic Botany》2005,83(3):219-226
The sinking and floating (density) of the special winter buds (turions) produced by many aquatic plants play important roles in their life cycles, yet there has been little experimental study of these phenomena. However, it has been postulated that starch determines the density of turions. In order to test this hypothesis, turions of Myriophyllum verticillatum L. were collected from October through April and analyzed for density, dry-to-fresh-weight ratio and starch content. Density did not correlate closely (R2 = 0.37) with the dry-to-fresh-weight ratios. Density strongly correlated (R2 = 0.99) with starch only in the January collections, but not at several other times, so starch content alone is not always the major determinant of turion density. Intracellular lacunae (potentially gas spaces) also occur within the axes of these turions, and the lacunal volumes increased ca. 20-fold as they resumed growth, at which time the turions started to float. Significantly, turions, which were near the density of water, could be sunk or floated by changing the ambient pressure (which would alter their internal gas volume). Thus, starch has a role in determining the density of M. verticillatum turions, but the amount of intercellular gas space may be more important, especially when they resume growth in the spring. 相似文献
6.
An analysis of expressed sequence tags of developing castor endosperm using a full-length cDNA library 总被引:2,自引:0,他引:2
Background
Castor seeds are a major source for ricinoleate, an important industrial raw material. Genomics studies of castor plant will provide critical information for understanding seed metabolism, for effectively engineering ricinoleate production in transgenic oilseeds, or for genetically improving castor plants by eliminating toxic and allergic proteins in seeds. 相似文献7.
Helena J Bailes Wayne L Davies Ann EO Trezise Shaun P Collin 《BMC evolutionary biology》2007,7(1):200
Background
One of the greatest challenges facing the early land vertebrates was the need to effectively interpret a terrestrial environment. Interpretation was based on ocular adaptations evolved for an aquatic environment millions of years earlier. The Australian lungfish Neoceratodus forsteri is thought to be the closest living relative to the first terrestrial vertebrate, and yet nothing is known about the visual pigments present in lungfish or the early tetrapods. 相似文献8.
Matthew W Blair Sharon JB Knewtson Carolina Astudillo Chee-Ming Li Andrea C Fernandez Michael A Grusak 《BMC plant biology》2010,10(1):215
Background
Iron deficiency anemia is a global problem which often affects women and children of developing countries. Strategy I plants, such as common bean (Phaseolus vulgaris L.) take up iron through a process that involves an iron reduction mechanism in their roots; this reduction is required to convert ferric iron to ferrous iron. Root absorbed iron is critical for the iron nutrition of the plant, and for the delivery of iron to the shoot and ultimately the seeds. The objectives of this study were to determine the variability and inheritance for iron reductase activity in a range of genotypes and in a low × high seed iron cross (DOR364 × G19833), to identify quantitative trait loci (QTL) for this trait, and to assess possible associations with seed iron levels. 相似文献9.
Non‐destructive allometric estimates of above‐ground and below‐ground biomass of high‐mountain vegetation in the Andes
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Aim
Studies that monitor high‐mountain vegetation, such as paramo grasslands in the Andes, lack non‐destructive biomass estimation methods. We aimed to develop and apply allometric models for above‐ground, below‐ground and total biomass of paramo plants.Location
The paramo of southern Colombia between 1°09′N and 077°50′W, at 3,400 and 3,700 m a.s.l.Methods
We established 61 1‐m2 plots at random locations, excluding disturbed, inaccessible and peat bog areas. We measured heights and basal diameters of all vascular plants in these plots and classified them into seven growth forms. Near each plot, we sampled the biomass from plants of abundant genera, after having measured their height and basal diameter. Hence, we measured the biomass of 476 plants (allometric set). For each growth form we applied power‐law functions to develop allometric models of biomass against basal diameter, height, height x basal diameter and height × basal area. The best models were selected using AICc weights. Using the observed and predicted plant biomass of the allometric set we calculated absolute percentage errors using cross‐validation. The biomass of a plot was estimated by summing the predicted biomass of all plants in a plot. Confidence limits around these sums were calculated by bootstrapping.Results
For groups of <20 plants the biomass predictions yielded large (>15%) errors. Applying groups that resembled the 1‐m2 plots in density and composition, the errors for above‐ground and total biomass estimates were <15%. Across all plots, we obtained an above‐ground, below‐ground and total plot biomass of 329 ± 190, 743 ± 486 and 1011 ± 627 g/m2 (mean ± SD), respectively. These values were within the range of biomass estimates obtained destructively in the tropical Andes.Conclusions
In new applications, if target vegetation samples are similar regarding growth forms and genera to our allometric set, their biomass might be predicted applying our equations, provided they contain at least 50–100 plants. In other situations, we would recommend gathering additional biomass measurements from local plants to evaluate new regression equations. 相似文献10.
11.
Lorella Navazio Barbara Baldan Roberto Moscatiello Anna Zuppini Sheridan L Woo Paola Mariani Matteo Lorito 《BMC plant biology》2007,7(1):41
Background
Calcium is commonly involved as intracellular messenger in the transduction by plants of a wide range of biotic stimuli, including signals from pathogenic and symbiotic fungi. Trichoderma spp. are largely used in the biological control of plant diseases caused by fungal phytopathogens and are able to colonize plant roots. Early molecular events underlying their association with plants are relatively unknown. 相似文献12.
Ping Kong Brett M Tyler Patricia A Richardson Bobby WK Lee Zhaohui S Zhou Chuanxue Hong 《BMC microbiology》2010,10(1):313
Background
Oomycetes attack a huge variety of economically and ecologically important plants. These pathogens release, detect and respond to signal molecules to coordinate their communal behaviors including the infection process. When signal molecules are present at or above threshold level, single zoospores can infect plants. However, at the beginning of a growing season population densities of individual species are likely below those required to reach a quorum and produce threshold levels of signal molecules to trigger infection. It is unclear whether these molecules are shared among related species and what their chemistries are. 相似文献13.
Stephanie Troufflard William Mullen Tony R Larson Ian A Graham Alan Crozier Anna Amtmann Patrick Armengaud 《BMC plant biology》2010,10(1):172
Background
Mineral fertilization and pest control are essential and costly requirements for modern crop production. The two measures go hand in hand because plant mineral status affects plant susceptibility to pests and vice versa. Nutrient deficiency triggers specific responses in plants that optimize nutrient acquisition and reprogram metabolism. K-deficient plants illustrate these strategies by inducing high-affinity K-uptake and adjusting primary metabolism. Whether and how K deficient plants also alter their secondary metabolism for nutrient management and defense is not known. 相似文献14.
Barbara Pauly Margherita Lasi Carol MacKintosh Nick Morrice Axel Imhof Jörg Regula Stephen Rudd Charles N David Angelika Böttger 《BMC cell biology》2007,8(1):31
Background
14-3-3 proteins have been implicated in many signalling mechanisms due to their interaction with Ser/Thr phosphorylated target proteins. They are evolutionarily well conserved in eukaryotic organisms from single celled protozoans and unicellular algae to plants and humans. A diverse array of target proteins has been found in higher plants and in human cell lines including proteins involved in cellular metabolism, apoptosis, cytoskeletal organisation, secretion and Ca2+ signalling. 相似文献15.
Background
DNA-dependent RNA polymerase IV and V (Pol IV and V) are multi-subunit enzymes occurring in plants. The origin of Pol V, specific to angiosperms, from Pol IV, which is present in all land plants, is linked to the duplication of the gene encoding the largest subunit and the subsequent subneofunctionalization of the two paralogs (NRPD1 and NRPE1). Additional duplication of the second-largest subunit, NRPD2/NRPE2, has happened independently in at least some eudicot lineages, but its paralogs are often subject to concerted evolution and gene death and little is known about their evolution nor their affinity with Pol IV and Pol V. 相似文献16.
Thilo C Fischer Barbara Meller Evelyn Kustatscher Rainer Butzmann 《BMC evolutionary biology》2010,10(1):337
Background
Structural elucidation and analysis of fructifications of plants is fundamental for understanding their evolution. In case of Ginkgo biloba, attention was drawn by Fujii in 1896 to aberrant fructifications of Ginkgo biloba whose seeds are attached to leaves, called O-ha-tsuki in Japan. This well-known phenomenon was now interpreted by Fujii as being homologous to ancestral sporophylls. The common fructification of Ginkgo biloba consists of 1-2 (rarely more) ovules on a dichotomously divided stalk, the ovules on top of short stalklets, with collars supporting the ovules. There is essentially no disagreement that either the whole stalk with its stalklets, collars and ovules is homologous to a sporophyll, or, alternatively, just one stalklet, collar and ovule each correspond to a sporophyll. For the transition of an ancestral sporophyll resembling extant O-ha-tsuki aberrant leaves into the common fructification with stalklet/collar/ovule, evolutionary reduction of the leaf lamina of such ancestral sporophylls has to be assumed. Furthermore, such ancestral sporophylls would be expected in the fossil record of ginkgophytes. 相似文献17.
18.
James F. White Kathryn I. Kingsley Kurt P. Kowalski Ivelisse Irizarry April Micci Marcos A. Soares Marshall S. Bergen 《Plant and Soil》2018,422(1-2):195-208
Background and aims
Non-native Phragmites australis (haplotype M) is an invasive grass that decreases biodiversity and produces dense stands. We hypothesized that seeds of Phragmites carry microbes that improve seedling growth, defend against pathogens and maximize capacity of seedlings to compete with other plants.Methods
We isolated bacteria from seeds of Phragmites, then evaluated representatives for their capacities to become intracellular in root cells, and their effects on: 1.) germination rates and seedling growth, 2.) susceptibility to damping-off disease, and 3.) mortality and growth of competitor plant seedlings (dandelion (Taraxacum officionale F. H. Wigg) and curly dock (Rumex crispus L.)).Results
Ten strains (of 23 total) were identified and characterized; seven were identified as Pseudomonas spp. Strains Sandy LB4 (Pseudomonas fluorescens) and West 9 (Pseudomonas sp.) entered root meristems and became intracellular. These bacteria improved seed germination in Phragmites and increased seedling root branching in Poa annua. They increased plant growth and protected plants from damping off disease. Sandy LB4 increased mortality and reduced growth rates in seedlings of dandelion and curly dock.Conclusions
Phragmites plants associate with endophytes to increase growth and disease resistance, and release bacteria into the soil to create an environment that is favorable to their seedlings and less favorable to competitor plants.19.
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