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1.
E. Nenz F. Pupilli F. Paolocci F. Damiani C. A. Cenci S. Arcioni 《Plant Cell, Tissue and Organ Culture》1996,45(2):145-152
Culture conditions have been established for callus induction and growth from different explants in L. angustissimus L. Calli were obtained from hypocotyls, leaves, stems, cotyledons and roots cultured on media containing 2,4-dichlorophenoxyacetic acid or -naphthaleneacetic acid with kinetin, N6 – 2 or benzyladenine in different combinations and concentrations. Only those calli induced in presence of -naphthaleneacetic acid with benzyladenine or kinetin produced shoots. Calli induced from hypocotyl explants were the most efficient in regeneration of shoots. Transformation with an Agrobacterium rhizogenes binary vector carrying the plasmid pBI 121.1 is reported. The percentage of cotransformation was estimated by testing GUS activity in hairy roots. The integration of Ri T-DNA and the NPTII gene in transformed plants was confirmed by molecular analyses and in vitro culture of transgenic tissues in the presence of kanamycin.Abbreviations BA
benzyladenine
- 2,4-d
2,4-dichlorophenoxyacetic acid
- 1AA
indole-3-acetic acid
- NAA
-naphthaleneacetic acid
- 2iP
N6 – 2
- PA
proanthocyanidins
- NOS
nopaline synthase
- NI TII
neomycin phosphotransferase
- GUS
-glucuronidase
- CaMV
cauliflower mosaic virus 相似文献
2.
F. Crea O. Calderini E. Nenz P. D. Cluster F. Damiani S. Arcioni 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1997,95(7):1112-1118
The aim of this study was to produce somatic hybrids between tetraploid (2n=4x=32) M. sativa and diploid (2n=2x=16) M. ?falcata and analyse their genomic structure. Protoplasts from genotypes selected for regeneration ability from the cultivar Rangelander of M. sativa and Wisfal-1 of M. falcata were electrofused. Seven somatic hybrid calli were produced and one of them regenerated plants. The hybrid nature of these plants and their genetic composition were assessed with morphological, cytological, and molecular analyses. The resulting plants were hyper-aneuploid (2n=33) and contained one extra long chromosome, indicating that a translocation had taken place. The presence of both types of parental sequences in the RAPDs analysis confirmed the true hybrid nature of the plants. Rearrangements within the parental genomes and the presence of somaclonal variation among hybrid plants were observed through an RFLP analysis of the nucleolar organizing region (NOR). The possible causes for the gross genomic alterations, and the suitability of this method for transferring useful agronomic traits from wild species to cultivated alfalfa, are discussed. 相似文献
3.
Synchronous population fluctuations occur in many species and have large economic impacts, but remain poorly understood. Dispersal, climate and natural enemies have been hypothesized to cause synchronous population fluctuations across large areas. For example, insect herbivores cause extensive forest defoliation and have many natural enemies, such as parasitoids, that may cause landscape‐scale changes in density. Between outbreaks, parasitoid‐caused mortality of hosts/herbivores is high, but it drops substantially during outbreak episodes. Because of their essential role in regulating herbivore populations, we need to include parasitoids in spatial modelling approaches to more effectively manage insect defoliation. However, classic host‐parasitoid population models predict parasitoid density, and parasitoid density is difficult to relate to host‐level observations of parasitoid‐caused mortality. We constructed a novel model to study how parasitoids affect insect outbreaks at the landscape scale. The model represents metacommunity dynamics, in which herbivore regulation, colonisation and extinction are driven by interactions with the forest, primary parasitoids and hyperparasitoids. The model suggests that parasitoid spatial dynamics can produce landscape‐scale outbreaks. Our results propose the testable prediction that hyperparasitoid prevalence should increase just before the onset of an outbreak because of hyperparasitoid overexploitation. If verified empirically, hyperparasitoid distribution could provide a biotic indicator that an outbreak will occur. 相似文献
4.
An efficient and rapid procedure for plantlet regeneration from chicory mesophyll protoplasts 总被引:2,自引:0,他引:2
An efficient procedure for plantlet regeneration from chicory mesophyll protoplasts has been developed in order to perform
protoplast fusion experiments. Protoplasts were isolated from a genotype of Italian red chicory (CH 363) and purified by centrifugation
in a solution containing 13% (w/v) sucrose to collect uniform protoplasts in size. After 2 days culture at a density of 2×104 protoplasts ml−1 of liquid medium, protoplasts were cultured following three different procedures: in liquid medium, stratified in semi-solid
medium, and embedded in Ca-alginate droplets. Four different media were used and culture procedures were evaluated recording
the protoplast viability, protoplast division frequency and plating efficiency for each experiment. The embedding of protoplasts
in Ca-alginate droplets enhanced both division frequency and plating efficiency for chicory mesophyll cells. Furthermore,
this procedure shortened the cycle of plant regeneration from protoplasts, which could be completed in eight weeks.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
5.
Fulvio Pupilli Francesco Damiani Elena Nenz Sergio Arcioni 《In vitro cellular & developmental biology. Plant》1992,28(4):167-171
Summary Nodes ofMedicago sativa, Lotus corniculatus, Lotus tenuis, andLotus pedunculatus were cultured on MS basal media with different growth regulators. InM. sativa each node produced one shoot and the apical dominance was unaffected by high levels of cytokinins, and subsequent cycles
of culture. Shoot development was stimulated by the presence ofN
6-isopentenyl-adenine in the culture medium and was dependent on the genotype of the explant. Shoot development was not affected
by the original position of the node on the plant nor by the plant age. Shoots rooted in MS medium gelled with starch and
containing 2 mg·liter−1 indol-3-acetic acid. In the threeLotus species, node culture was a more effective technique than inM. sativa. The number of shoots per node increased with the time of culture and with the presence of 0.05 mg·liter−1 of 6-benzylaminopurine. The highest number of shoots derived from one node was achieved inL. pedunculatus and inL. tenuis by culturing single nodes, whereas inL. corniculatus stem segments had to be totally covered by the medium for success. Rooting was easily achieved in MS medium with or without
auxins. 相似文献
6.
E. Nenz F. Pupilli F. Damiani S. Arcioni 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1996,93(1-2):183-189
Interspecific somatic hybrid plants were obtained by symmetrical electrofusion of mesophyll protoplasts of Medicago sativa with callus protoplasts of Medicago arborea. Somatic hybrid calli were picked manually from semi-solid culture medium after they were identified by their dual color in fluorescent light. Twelve putative hybrid calli were selected and one of them regenerated plants. The morphogenesis of the somatic hybrid calli was induced by the synthetic growth regulator 1,2 benzisoxazole-3-acetic acid. Somatic hybrid plants showed intensive genome rearrangements, as evidenced by isozyme and RFLP analysis. The morphology of somatic hybrid plants was in general intermediate between the parents. The production of hybrids by protoplast fusion between sexually incompatible Medicago species is related to the in vitro respon siveness of the parental protoplasts. The possibility of using somatic hybrid plants in alfalfa breeding is discussed. 相似文献
7.
Production of asymmetric somatic hybrid plants between Cichorium intybus L. and Helianthus annuus L.
S. Varotto E. Nenz M. Lucchin P. Parrini 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2001,102(6-7):950-956
In order to obtain male-sterile asymmetric somatic hybrids between chicory (Cichorium intybus L.) and a sunflower (Helianthus annuus L.) male-sterile cytoplasmic line, mesophyll chicory protoplasts inactivated with iodoacetic acid and hypocotyl sunflower
protoplasts irradiated with γ-rays have been fused, using PEG and applying two different procedures. Thirty three plants were
regenerated from putative hybrid calli. A cytological analysis of their root-tip cells indicated that most of them had 18
chromosomes, the same number as chicory. Through Southern hybridisation on total DNA using the maize mitochondrial specific
gene probes Cox I, Cox II and Cob, three plants were identified as cytoplasmic asymmetric hybrids, as shown by hybridisation
bands specific for both chicory and sunflower. One of the regenerated plants produced a novel pattern of hybridisation that
was not detected in either parent. When hybridisation of total DNA was carried out with an atpA mitochondrial gene probe the
same three cybrids presented both the fertile chicory fragment and the male-sterile sunflower fragment. Finally, Southern
hybridisation with an ORF 522 probe, which in sunflower is co-transcribed with the atpA gene, confirmed the hybrid nature
of the three plants. The morphology of the cybrids resembled the parental chicory phenotype, and at anthesis their anthers
produced fewer pollen grains which could not germinate either ”in vitro” or ”in situ.” Cybrid plants grown in the field produced
seeds when free-pollination occurred.
Received: 26 April 2000 / Accepted: 28 August 2000 相似文献
8.
Most evidence of climate change impacts on food webs comes from modern studies and little is known about how ancient food webs have responded to climate changes in the past. Here, we integrate fossil evidence from 71 fossil sites, body-size relationships and actualism to reconstruct food webs for six large mammal communities that inhabited the Iberian Peninsula at different times during the Quaternary. We quantify the long-term dynamics of these food webs and study how their structure changed across the Quaternary, a period for which fossil data and climate changes are well known. Extinction, immigration and turnover rates were correlated with climate changes in the last 850 kyr. Yet, we find differences in the dynamics and structural properties of Pleistocene versus Holocene mammal communities that are not associated with glacial-interglacial cycles. Although all Quaternary mammal food webs were highly nested and robust to secondary extinctions, general food web properties changed in the Holocene. These results highlight the ability of communities to re-organize with the arrival of phylogenetically similar species without major structural changes, and the impact of climate change and super-generalist species (humans) on Iberian Holocene mammal communities. 相似文献
9.
demoniche is a freely available R‐package which simulates stochastic population dynamics in multiple populations of a species. A demographic model projects population sizes utilizing several transition matrices that can represent impacts on species growth. The demoniche model offers options for setting demographic stochasticity, carrying capacity, and dispersal. The demographic projection in each population is linked to spatially‐explicit niche values, which affect the species growth. With the demoniche package it is possible to compare the influence of scenarios of environmental changes on future population sizes, extinction probabilities, and range shifts of species. 相似文献
10.
Y. Zafar E. Nenz F. Damiani F. Pupilli S. Arcioni 《Plant Cell, Tissue and Organ Culture》1995,41(1):41-48
Plant regeneration from explant and protoplast derived callus has been achieved in Medicago littoralis cv. Harbinger 1886, an annual legume resistant to the fungus Pseudopeziza medicaginis. Callus was induced from different tissue explants and the fastest growth rate was observed for hypocotyls in B5 medium with 2 mg l–1 2,4-dichlorophenoxyacetic acid and 0.5 mg l–1 N6-benzyladenine. Protoplasts were isolated from cotyledons and leaves of sterile plants and from callus; the first two kinds of protoplasts showed a plating efficiency of 5.6% and 5%, respectively, when embedded in agarose. Plant regeneration occurred on media containing % MathType!MTEF!2!1!+-% feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr% 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9% vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9qq-f0-yqaqVeLsFr0-vr% 0-vr0db8meaabaqaciGacaGaaeqabaWaaeaaeaaakeaacaqGobWaaW% baaSqabeaacaqG2aaaaOGaaeOVfiaabs5adaahaaWcbeqaaiaaikda% aaGccaqG+waaaa!3F97!\[{\text{N}}^{\text{6}} {\text{\Delta }}^2 {\text{}}\]isopentenyl-adenine combined with indole-3-acetic acid or 1,2-benzisoxazole-3-acetic acid, and on media with N6-benzyladenine plus -naphtaleneacetic acid; a cytokinin/auxin ratio higher than 1 induced embryos while a ratio around 1 stimulated shoot formation. Embryo development and rooting of shoots were performed in RL medium without growth regulators.Abbreviations NAA
-naphthaleneacetic acid
- BA
N6-benzyladenine
- 2,4-D
2,4-dichlorophenoxyacetic acid
- 2iP
% MathType!MTEF!2!1!+-% feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr% 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9% vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9qq-f0-yqaqVeLsFr0-vr% 0-vr0db8meaabaqaciGacaGaaeqabaWaaeaaeaaakeaacaqGobWaaW% baaSqabeaacaqG2aaaaOGaaeOVfiaabs5adaahaaWcbeqaaiaaikda% aaGccaqG+waaaa!3F97!\[{\text{N}}^{\text{6}} {\text{\Delta }}^2 {\text{}}\]isopentenyl-adenine
- IAA
indole-3-acetic acid
- BOA
1,2-benzisoxazole-3-acetic acid
- KIN
kinetin
- MS
Murashige & Skoog (1962)
- GRFMS
growth regulator free MS medium
- B5
Gamborg et al. (1968)
- RL
Phillips & Collins (1979)
- KM8
KM8P Kao & Michayluk (1975)
- CPW
Frearson et al. (1973)
- f. wt
fresh weight
- FDA
fluorescoin diacetate 相似文献