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1.
A. Akkak V. Scariot D. Torello Marinoni P. Boccacci C. Beltramo R. Botta 《Biologia Plantarum》2009,53(1):164-166
Forty one simple sequence repeats were isolated from two microsatellite enriched libraries of date palm (Phoenix dactylifera L.). After screening, 17 selected microsatellite loci were characterized and evaluated on a set of 31 cultivars and clones
from Algerian and Californian germplasm. All primer pairs produced an amplification product of the expected size and detected
high polymorphism among the analysed samples. These nuclear simple sequence repeat (SSR) markers are expected to be a very
effective tool for evaluating genetic diversity in date palm germplasm. Acrosstaxa amplification showed the usefulness of
most SSR markers in 14 other species across the genus Phoenix. 相似文献
2.
Somatic embryos were obtained from immature zygotic embryos of Cedrela fissilis Well. (Meliaceae), after a culture period of 12 months, with regular subcultures every 6–8 weeks. Callus was developed on explants in 2 months
on Murashige and Skoog (MS) medium containing 2,4 dichlorophenoxyacetic acid (2,4-D) or picloram (PIC). When the calli were
transferred to fresh medium, embryogenic tissue appeared on MS + 45 μM 2,4-D, or 22.5 μM 2,4-D + 0.4 μM 6-benzyladenine (BA),
or 20.7 μM PIC after 6 months. Sub-culture of embryogenic tissue in MS medium supplemented with 4.5 μM 2,4-D resulted in the
differentiation into somatic embryos after further 4 months. Repeated secondary somatic embryogenesis was achieved by regular
subculture on this medium. Maturation and conversion of somatic embryos into plantlets was achieved on MS medium without plant
growth regulators and the conversion frequency was approximately 12.5 %. The plantlets were successfully acclimatized in pots
with soil. Histological studies showed that somatic embryos had no detectable connection with the mother explants and that
somatic embryos in advanced stages were bipolar with shoot and root apical meristems, they contained vascular system and showed
typical characteristics of a somatic dicotyledonous embryo. 相似文献
3.
Indian mustard (Brassica juncea L. cv. Vitasso) plants exposed to 10, 30, 50 and 100 μM of Cd for 5 d in hydroponic culture were analysed with reference
to the distribution of Cd2+, the accumulation of biomass and antioxidants and antioxidative enzymes in leaves. Cd induced a decrease in plant biomass.
The maximum accumulation of Cd occurred in roots followed by stems and leaves. Cd induced a decrease in catalase (CAT) and
guiacol peroxidase (GPX) activities but an increase in ascorbate peroxidase (APX) and monodehydroascorbate reductase (MDHAR)
activities. Enhancement in dehydroascorbate reductase (DHAR) activity was also at 10 μM Cd. Glutathione reductase (GR) activity
showed pronounced stimulation after all treatments, but glutathione S-transferase (GST) and glutathione peroxidase (GPOX)
activities decreased. The effectiveness of ascorbate-glutathione cycle (AGC) was determined by the ratio of ascorbate to H2O2. This ratio decreased in the Cd-treated leaves which indicated that the cycle was disordered. 相似文献
4.
In this study we examined the genetic diversity and geographic scale of genotype distribution within the model legume species
Medicago truncatula widely distributed in pasture and marginal agricultural lands in Greece and other Mediterranean countries. Thirty one Medicago truncatula and Medicago littorialis accessions were chosen on the basis of their geographical distributions and studied using 9 polymorphic simple sequence repeats
(SSR) markers. The number of alleles per locus varied between 3 and 7. A total of 42 alleles were detected with a mean value
of 4.66 alleles per locus. Geographic origin was not related with genotypic similarity among accessions. However, there were
instances of close genetic relatedness between accessions from neighboring locations in a geographic compartment. In conclusion,
the presented data revealed extensive M. truncatula genotype dispersal in Greece pointing to the significance of preserving local genetic resources in their natural environment. 相似文献
5.
A glutathione S-transferase (GST) gene cloned from the lepidopteran spruce budworm, Choristoneura fumiferana Clem. was transformed into the model plant Arabidopsis thaliana. The CfGST-transgenic and wild-type A. thaliana were subjected to 4 and 10 °C for 48 h and their cold resistance was studied. The GST activity of the transgenic plants was
46.6 and 35.7 % higher than that of the wild-type plants after 48 h under 4 and 10 °C, respectively. Relative membrane permeability
and malondialdehyde content in the transgenic plants were lower while contents of the chlorophyll and proline were higher
than those in the wild-type plants under 4 and 10 °C. The survival rate of the transgenic plants was 43.7 % for 24 h under
0 °C, while survival rate of wild-type plants was 28.3 %. The results indicated that the insect GST could enhance cold resistance
in the transgenic A. thaliana. 相似文献
6.
We quantified inbreeding depression for fruit production, embryo vitality and seed germination in three deceptive orchids,
Serapias vomeracea, S. cordigera and S. parviflora, which do not provide any reward to their pollinators, and are predicted to experience high outcrossing. Of the three species
examined only S. parviflora was autonomously selfing. Both S. vomeracea and S. cordigera showed highly significant differences in fitness between selfed and outcrossed progenies, resulting in high levels of inbreeding
depression, which increased in magnitude from seed set to seed germination. Inbreeding depression may promote outcrossing
in Serapias by acting as a post-pollination barrier to selfing. Cumulative inbreeding depression across three stages in S. parviflora was lower that in both outcrossing species. The large difference in germination between selfed and outcrossed seeds is an
important issue in conservation biology. 相似文献
7.
The effect of in vitro cultivation of donor shoots on subsequent morphogenesis in leaf explants of quince (Cydonia oblonga Mill.) clone BA29 was investigated. Proliferating donor shoots were cultured in ventilated or closed vessels under different
photosynthetic photon flux densities (PPFD; 200 and 100 μmol m−2 s−1) with 0, 15, 30 g dm−3 sucrose. Shoots grown in ventilated vessels, especially with sucrose at 15 or 30 g dm−3, were better developed with fully expanded leaves compared to those in standard closed vessels. Leaves collected from pre-treated
donor shoots were used to assess regeneration capacity. Somatic embryo production was highest in leaves harvested from shoots
cultured in closed vessels with 30 g dm−3 sucrose and in ventilated vessels with 15 and 30 g dm−3 sucrose and under high PPFD which was, in comparison with the control treatment (closed vessel, 30 g dm−3 sucrose and low PPFD), about 2 to 2.5 times higher. A similar response was observed for root regeneration. 相似文献
8.
A. I. Cordeiro J. F. Sanchez-Sevilla M. C. Alvarez-Tinaut M. C. Gomez-Jimenez 《Biologia Plantarum》2008,52(4):642-647
Eighty seven olive (Olea europaea ssp. sativa L.) cultivar accessions from Portugal were characterized by means of randomly amplified polymorphic DNA (RAPD) markers. Of
the 11 arbitrary 10-mer primers tested a total of 92 polymorphic bands were obtained, representing 87.6 % of the total amplification
products. Twenty nine different genotypes were clearly discriminated. Differences were not found among the amplification profiles
from different individuals of the same cultivar. All the genotypes could be identified by the combination of three primers:
OPR-1, OPK-14 and OPA-1, seven genotype-specific markers being detected. Genetic relationships were estimated by the unweighted
pair-group method with arithmetic averaging (UPGMA). The genetic analysis of the results showed a gradual distance between
the various cultivars, making it difficult to identify well-differentiated phylogenetic groups, although two clusters were
distinguishable with 35 % similarity, in addition to three independent branches with lower similarity: Galega, Tentilheira
and Redondal. The dendrogram reflect some relationships for most of the cultivars according to the use of the fruit and ecological
adaptation. 相似文献
9.
Effect of nitrate availability on nitrate reduction was examined in inter-connected ramets of invasive clonal plant Eichhornia crassipes grown with two nitrate supply regimes during different clonal growth stage. Increase of nitrate availability accelerated
nitrate reductase activity (NRA) in parent and offspring ramets of E. crassipes, and there was greatly different pattern in inter-connected ramets during clonal growth stage. Leaf NRA was lower in offspring
than that in parent ramets in phase 1, while significantly higher leaf NRA in offspring ramets was detected during phase 2.
The results indicated NRA in inter-connected ramets of E. crassipes was highly dependent on nitrate availability and growth stage. 相似文献
10.
One of the least understood enzymatic steps in chlorophyll biosynthesis is the formation of isocyclic ring, which is catalyzed
by the Mg-protoporphyrin IX monomethyl ester (MgPME) cyclase that is involved in the conversion of MgPME to protochlorophyllide.
Several genes encoding part of this enzyme have been identified and functional analysis of them has been performed. The enzyme
plays important roles in higher plants and photosynthetic bacteria. The review focuses on the current knowledge of MgPME cyclase
coding genes, with emphasis on their organization, expression pattern, and functional analysis obtained from mutants. 相似文献
11.
E. C. R. Tavano L. C. L. Stipp F. R. Muniz F. A. A. Mour?o Filho B. M. J. Mendes 《Biologia Plantarum》2009,53(2):395-399
In vitro organogenesis of Citrus volkameriana and C. aurantium was studied considering three explant types: epicotyl segment, internodal segment, and hypocotyl segment with attached cotyledon
fragment. The explants were cultured in medium according to Grosser and Gmitter (EME) supplemented with 0, 0.5, 1.0, 1.5,
and 2.0 mg dm− 3 6-benzyl-aminopurine (BAP), incubated firstly in darkness for 4 weeks, and then transferred to 16-h photoperiod for 2 weeks.
Comparing epicotyl and internodal segments, a higher percentage of responsive explants and a higher number of shoots per explant
were obtained with epicotyl segments, regardless of the BAP concentration. For C. volkameriana the highest percentage of responsive epicotyl segments (42 %) was obtained in EME with 1.0 mg dm−3 BAP, while for C. aurantium (59 %) in EME with 0.5 mg dm−3 BAP. The organogenesis efficiency was the best with the use of the hypocotyl segment with attached cotyledon fragment (77
% for C. volkameriana and to 75 % for C. aurantium). With this explant the morphogenesis occurred only in the hypocotyl region. The in vitro organogenesis was characterized by histological analyses showing that the morphogenic process started in the cambium region
near the explant cut end. 相似文献
12.
The pattern of the activity of arginine decarboxylase (ADC) and omithine decarboxylase (ODC) involved in polyamine synthesis
in ripening wheat seeds was examined. The aim was to study the polyamines and the activity of the two enzymes in correlation
with the growth processes occurring in the developing wheat seeds. The results obtained showed a very different pattern of
polyamine content in the two organs of caryopsis, and that the two enzymes in the embryos have a higher activity than in the
endosperms. Moreover, while in the embryos the ADC exhibits higher activity than the ODC, in the endosperms the activity of
ODC is about similar to that of ADC. This pattern is discussed in relation to the different histological characteristics of
embryo and endosperm tissues during seed development. 相似文献
13.
Modelling the dynamics of the electron transport rate measured by PAM fluorimetry during Rapid Light Curve experiments 总被引:1,自引:0,他引:1
We propose a dynamic model specifically designed to simulate changes in the photosynthetic electron transport rate, which
is calculated from fluorescence measurements when plants are exposed, for a short time, to a series of increasing photon flux
densities. This model simulates the dynamics of the effective yield of photochemical energy conversion from the maximum and
natural chlorophyll fluorescence yields, taking into account a cumulative effect of successive irradiations on photosystems.
To estimate a characteristic time of this effect on photosystems, two series of experiments were performed on two benthic
diatom culture concentrations. For each concentration, two different series of irradiations were applied. Simplified formulations
of the model were established based on the observed fluorescence curves. The simplified versions of the model streamlined
the parameters estimation procedure. For the most simplified version of the model (only 4 parameters) the order of magnitude
of the characteristic time of the residual effect of irradiation was about 38 s (within a confidence interval between 20 and
252 s). The model and an appropriate calibration procedure may be used to assess the physiological condition of plants experiencing
short time-scale irradiance changes in experimental or field conditions. 相似文献
14.
Diurnal cycle of chlorophyll fluorescence parameters was done in Colocasia esculenta L. (swamp taro) grown in marshy land under sun or under shade. The sun leaves maintained higher electron transport rate (ETR)
and steady state to initial fluorescence ratio (Fs/F0) than shade leaves. In spite of lower ETR, higher photochemical quenching (PQ), and effective quantum yield of photosystem
2 (ΦPS2) was evident in shade plants compared to plants exposed to higher irradiance. ETR increased linearly with increase in irradiance
more under low irradiance (r
2 = 0.84) compared to higher irradiance (r
2 = 0.62). The maximum quantum yield of PS 2 (Fv/Fm) did not differ much in sun and shade leaves with the exception of midday when excess of light energy absorbed by plants
under sun was thermally dissipated. Hence swamp taro plants adopted different strategies to utilize radiation under different
irradiances. At higher irradiance, there was faster decline in proportion of open PS 2 centers (PQ) and excess light energy
was dissipated through non-photochemical quenching (NPQ). Under shade, absorbed energy was effectively utilized resulting
in higher ΦPS2. 相似文献
15.
I. A. Feria-Romero H. Astudillo-de la Vega M.A. Chavez-Soto E. Rivera-Arce M. López H. Serrano X. Lozoya 《Biologia Plantarum》2009,53(1):125-128
We used a random amplified polymorphic DNA (RAPD) amplification method to identify molecular markers associated with high
quercetin accumulation in the leaves of Psidium guajava L. trees, selected from four different Mexican agronomic regions. We identified six polymorphic RAPD fragments of 620, 590,
370, 690, 480 and 460 bp among individuals of P. guajava. Genetic linkage disequilibrium analysis revealed that three RAPD profiles considered as DNA markers (620/590 bp, 370 bp
and 480/460 bp) had a positive, direct association with quercetin content. These informative molecular markers can be used
for selective identification of plants with the highest accumulation of flavonoids. 相似文献
16.
In this study, Dendrobium Sonia 17 plantlets were used to induce in vitro flowering. Inflorescences were induced and rooting was inhibited in the half-strength Murashige and Skoog medium containing
20 μM N
6-benzyladenine (BA). The medium with high P and low N contents was effective to induce inflorescences while the medium with
low P and high N contents was only effective to promote forming of shoots. In addition, the induced in vitro inflorescences were able to multiply and maintain without exhibiting a distinctive vegetative phase. Different morphologies
of in vitro flowers such as incomplete flower structures, abnormal and unresupinated in vitro flowers were observed. 相似文献
17.
Ethylene production and growth of callus cultures of lavandin (Lavandula offidnalis Cham x Lavandula latifolia Villars) cv.
Grosso were examined. Callus lines, derived from various kinds of primary expiants (shoot tip, leaf and calyx), exhibited
differences in ethylene production patterns independent of callus growth. Moreover these differences could not be ascribed
to the expiant source. Within a line, ethylene pattern paralleled callus growth curve. Variations in ethylene evolution were
induced in shoot tip callus by means of ACC, AVG and varied amounts of 2,4-D in the culture medium. Following all these treatments
callus growth was not altered. Hie decrease in 2,4-D concentration caused changes in Chl a and water content of the tissues. 相似文献
18.
C. -W. Zhu J. -G. Zhu G. Liu Q. Zeng Z. -B. Xie J. Pang Z. -Z. Feng H. -Y. Tang L. Wang 《Photosynthetica》2008,46(2):318-320
Net photosynthetic rate (P
N) of ear and flag leaf during grain filling stage and grain yield of plants with non-darkened or darkened flag leaf or darkened
ear were examined in two different CO2 concentrations: ambient (AC) and AC+200 μmol mol−1 (EC). Ear showed much higher enhancement (56 %) of P
N than flag leaf (23 %) under EC. Moreover, CO2 enrichment shortened the photosynthetic duration of flag leaf relative to ear. In this way the ratio of ear to flag leaf
contribution to grain yield increased from 1.18 (AC) to 1.39 (EC). 相似文献
19.
To examine the hypothesis that stomatal behavior of plants in dry soil is influenced by a slow recovery from daytime water
deficit, we studied the effect of repeated wetting of leaves during evening and night in Cryptomeria japonica seedlings grown in dry soil. After 7 and 10 days of leaf wetting treatment the midday leaf water potential decreased and
the transpiration rate increased, respectively. Therefore, we suggest that rapid recovery from daytime water deficit could
weaken the water conserving stomatal behavior that adapts to drought conditions in the roots. 相似文献
20.
Donghua Liu Ping Xue Qingmin Meng Jing Zou Jiegang Gu Wusheng Jiang 《Plant cell reports》2009,28(4):695-702
The effects of lead and copper on the arrangement of microtubule (MT) cytoskeleton in root tip cells of Allium sativum L. were investigated. Batch cultures of garlic were carried out under defined conditions in the presence 10−4 M Pb/Cu of various duration treatments. With tubulin immunolabelling and transmission electron microscopy (TEM), we found
four different types of MT structures depending on the cell cycle stage: the interphase array, preprophase band, mitotic spindle
and phragmoplast were typical for the control cells. Pb/Cu affected the mechanisms controlling the organization of MT cytoskeleton,
and induces the following aberrations in interphase and mitotic cells. (1) Pb/Cu induced the formation of atypical MT arrays
in the cortical cytoplasm of the interphase cells, consisting of skewed, wavy MT bundles, MT fragments and ring-like tubulin
aggregations. (2) Pb/Cu disordered the chromosome movements carried out by the mitotic spindle. The outcome was chromosome
aberrations, for example, chromosome bridges and chromosome stickiness, as well as inhibition of cells from entering mitosis.
(3) Depending on the time of exposure, MTs disintegrated into shorter fragments or they completely disappeared, indicating
MT depolymerization. (4) Different metals had different effects on MT organization. MTs were more sensitive to the pressure
of Cu ions than Pb. Moreover, TEM observations showed that the MTs were relatively short and in some places wavy when exposed
to 10−4 M Pb/Cu solutions for 1–2 h. In many sections MTs were no longer visible with increasing duration of treatment (>4 h). Based
on these results, we suggested that MT cytoskeleton is primarily responsible for Pb/Cu-associated toxicity and tolerance in
plants. 相似文献