共查询到20条相似文献,搜索用时 15 毫秒
1.
Pancratium maritimum L. is an Amaryllidaceous species whose presence is severely endangered in its original range, the sandy coasts of the Mediterranean sea. A molecular analysis has been performed to evaluate the genetic distance among populations coming from different locations, in order to define the best repopulating strategy. The plant genome, analysed by AFLP markers, was found to be extremely homogeneous and conserved, evoking vegetative or autogamous reproductive habits. Seeds from two different locations showed a good germination capability in greenhouse tests, indicating the potential presence of an efficient sexual reproduction. The combination of molecular data and germination tests would support the hypothesis of an autogamous reproduction for this species. 相似文献
2.
Francisco Palma Carmen Lluch Carmen Iribarne Jose M. García-Garrido Noel A. Tejera García 《Plant Growth Regulation》2009,58(3):307-316
It has been shown that salicylic acid (SA) acts as an endogenous signal molecule responsible for inducing abiotic stress tolerance
in plants. The effect of SA and sodium chloride (NaCl) on growth, metabolite accumulation, oxidative stress and enzymatic
and non-enzymatic antioxidant responses on common bean plants (Phaseolus vulgaris, cv. F-15) was studied. Results revealed that either SA or NaCl decrease, shoot, root and total plant dry weights. SA treatments
decreased the contents of proline, and reduced forms of ascorbate and glutathione, however, the content of soluble sugars
(TSS), thiobarbituric acid-reactive substances (TBARs) and oxidized ascorbate remained unaffected. On the other hand, salinity
significantly reduced the levels of endogenous SA but increased the content of proline, soluble sugars, TBARs, ascorbate and
glutathione, as well as all increasing the levels of antioxidant enzyme activities assayed, except CAT. The application of
SA improved the response of common bean plants to salinity by increasing plant dry weight and decreasing the content of organic
solutes (proline and TSS) and damage to the membrane (TBARs). Moreover, SA application under saline conditions decreased the
levels of antioxidant enzyme activities POX, APX and MDHAR which could indicate successful acclimatization of these plants
to saline conditions. 相似文献
3.
Transgenic cotton (Gossypium hirsutum L.) lines expressing the tobacco glutathione S-transferase (GST) Nt107 were evaluated for tolerance to chilling, salinity, and herbicides, antioxidant enzyme activity, antioxidant compound levels, and lipid peroxidation. Although transgenic seedlings exhibited ten-fold and five-fold higher GST activity under normal and salt-stress conditions, respectively, germinating seedlings did not show improved tolerance to salinity, chilling conditions, or herbicides. Glutathione peroxidase (GPX) activity in transgenic seedlings was 30% to 60% higher under normal conditions, but was not different than GPX activity in wild-type seedlings under salt-stress conditions. Glutathione reductase, superoxide dismutase, ascorbate peroxidase, and monodehydroascorbate reductase activities were not increased in transgenic seedlings under salt-stress conditions, while dehydroascorbate reductase activity was decreased in transgenic seedlings under salt-stress conditions. Transgenic seedlings had 50% more oxidized glutathione when exposed to salt stress. Ascorbate levels were not increased in transgenic seedlings under salt-stress conditions. Malondialdehyde content in transgenic seedlings was nearly double that of wild-type seedlings under normal conditions and did not increase under salt-stress conditions. These results show that expression of Nt107 in cotton does not provide adequate protection against oxidative stress and suggests that the endogenous antioxidant system in cotton may be disrupted by the expression of the tobacco GST. 相似文献
4.
Cheruth Abdul Jaleel Ragupathi Gopi Paramasivam Manivannan Rajaram Panneerselvam 《Acta Physiologiae Plantarum》2007,29(3):205-209
The effect of paclobutrazol, a plant growth regulator, on antioxidant defense system was investigated in Catharanthus roseus (L.) G. Don. plants subjected to NaCl stress. The growth parameters were significantly reduced under 80 mM NaCl treatment;
however, this growth inhibition was less in paclobutrazol-treated (15 mg l−1 plant−1) plants. The non-enzymatic antioxidants ascorbic acid and reduced glutathione were affected under NaCl stress and they increased
significantly under paclobutrazol treatment when compared to NaCl treated as well as control plants (P ≤ 0.05). The activity of antioxidant enzyme ascorbate peroxidase showed a significant enhancement under salinity stress.
The catalase activity decreased in roots of NaCl-treated plants, but recovered with paclobutrazol treatment. The results suggested
that paclobutrazol have significant role in contributing salt stress tolerance of C. roseus by improving the components of antioxidant defense system. 相似文献
5.
The present study examined the possibility of increasing the contents of some bioactive compounds of Spirulina platensis cultivated in medium containing various hydrogen peroxide concentrations (2, 4, 6 and 8 mM) as a model for environmental
stress. A positive correlation was observed between the increase of H2O2 and increasing amounts of cellular lipophilic antioxidants (total carotenoids and α-tocopherol) and hydrophilic antioxidants
[glutathione (GSH) and ascorbic acid (AsA)]. HPLC profile of carotenoids revealed that algae responded to the change of H2O2 exposure by the accumulation of higher amounts of β-carotene, astaxanthine, luteine, zeaxanthin and cryptoxanthin. S. platensis showed significant linear increase in activities of antioxidant enzymes, i.e., catalase (CAT), peroxidase (PX), ascorbate
peroxidase (APX) and superoxide dismutase (SOD), with increasing H2O2 concentrations. A pronounced increase of oxidative lesions’ indexes [thiobarbituric acid reactive substances (TBARS) and
paramagnetic radical-EPR signal] was found in algal grown at 8 mM H2O2. These data revealed that S. platensis behaved with different strategies against H2O2 exposure which is dose dependent and their response strongly correlated with the scavenging enzymes (SOD, CAT, PX and APX)
and antioxidant compounds (GSH, AsA, β-carotene, astaxanthine and α-tocopherol) in the antioxidant defense systems. Therefore,
S. platensis could be considered as good candidates for successful cultivation in artificial open ponds under different environmental
conditions, as high value health foods, functional foods and as source of wide spectrum of nutrients. 相似文献
6.
Zahir Ahmad Zahir Usman Ghani Muhammad Naveed Sajid Mahmood Nadeem Hafiz Naeem Asghar 《Archives of microbiology》2009,191(5):415-424
Ethylene synthesis is accelerated in response to various environmental stresses like salinity. Ten rhizobacterial strains
isolated from wheat rhizosphere taken from different salt affected areas were screened for growth promotion of wheat under
axenic conditions at 1, 5, 10 and 15 dS m−1. Three strains, i.e., Pseudomonas putida (N21), Pseudomonas aeruginosa (N39) and Serratia proteamaculans (M35) showing promising performance under axenic conditions were selected for a pot trial at 1.63 (original), 5, 10 and 15 dS m−1. Results showed that inoculation was effective even in the presence of higher salinity levels. P. putida was the most efficient strain compared to the other strains and significantly increased the plant height, root length, grain
yield, 100-grain weight and straw yield up to 52, 60, 76, 19 and 67%, respectively, over uninoculated control at 15 dS m−1. Similarly, chlorophyll content and K+/Na+ of leaves also increased by P. putida over control. It is highly likely that under salinity stress, 1-aminocyclopropane-1-carboxylic acid-deaminase activity of
these microbial strains might have caused reduction in the synthesis of stress (salt)-induced inhibitory levels of ethylene.
The results suggested that these strains could be employed for salinity tolerance in wheat; however, P. putida may have better prospects in stress alleviation/reduction. 相似文献
7.
Propagation by softwood canes and cuttings is preferred as a practical system for vegetative reproduction of many ornamental
plant species, despite the advances in tissue culture techniques. Dracaena purplecompacta L. is a species that has a high demand for exports. Conversely, coconut water (CW) is a rich supplement that naturally contains
plant growth regulators such as indole acetic acid (IAA). The objective of this work was to evaluate the potential of CW extracts
containing natural IAA, on adventitious root development in vegetative propagation of ornamental plant canes of D. purplecompacta L. Five different concentrations (28, 57, 143, 286, 571 μM of natural IAA) of CW extracts were tested. Another set of treatment
was carried out with the same concentrations of authentic IAA hormone for comparison purpose. The 143-μM IAA CW extract recorded
the best root induction and development. It was found that the root expression was faster (5 weeks) with the use of the novel
method. In the conventional method, the canes are propagated by quick dip application of commercial product containing artificial
hormone IAA and placing them on coir fiber dust beds. It takes up to 6 weeks for the canes to develop adventitious roots to
the desired level. Steeping canes in 143-μM IAA CW extract improved rooting in D. purplecompacta L., and it was comparable to the application of 143-μM authentic IAA. The study indicates that adventitious root development,
shoot development, and leaf emergence of D. purplecompacta L. is promoted by IAA CW extracts. 相似文献
8.
An efficient procedure for direct organogenesis and regeneration of hop (Humulus lupulus L.) was established. For the first time Agrobacterium-mediated genetic transformation of hop (cv. "Tettnanger") was achieved. Shoot internodes from in vitro cultures were identified as the most suitable type of explant for regeneration. Using this type of explant, a shoot-inducing medium was developed that supported direct organogenesis of approximately 50% of the explants. Plantlets were successfully rooted and transferred to the greenhouse. Overall, in less than 6 months hop cultures propagated in vitro were regenerated to plants in the greenhouse. Agrobacterium-mediated genetic transformation was performed with the reporter gene GUS (-glucuronidase). The presence and function of transgenes in plants growing in the greenhouse was verified by PCR (polymerase chain reaction) and enzyme assay for GUS activity, respectively. We have obtained 21 transgenic plants from 1,440 explants initially transformed, yielding an overall transformation efficiency of 1.5%.Abbreviations BAP 6-Benzylaminopurine - GA3 Gibberellic acid - GUS -Glucuronidase - IAA Indole-3-acetic acid - IBA Indole-3-butyric acid - NAA -Naphthaleneacetic acid - nptII Neomycin phosphotransferase II - PCR Polymerase chain reaction - TDZ 1-Phenyl-3-(1,2,3-thiadiazol-5-yl) urea (thidiazuron)Communicated by H. Lörz 相似文献
9.
Ying Li Yuping Song Gongjun Shi Jianjun Wang Xilin Hou 《Acta Physiologiae Plantarum》2009,31(1):155-162
Changes in ascorbic acid content and antioxidant enzyme activities were investigated in non-heading Chinese cabbage (Brassica campestris ssp. chinensis Makino) leaves of ‘Wutacai’ and ‘Erqing’ exposed to excess copper (Cu). Cu treatment reduced the fresh weight of shoot and
root by 57% and 46% in ‘Wutacai’, and 60 and 54% in ‘Erqing’, respectively. The accumulation of copper in leaves was higher
in ‘Wutacai’ than that in ‘Erqing’. Compared to the control, ascorbic acid (AsA) contents were significantly decreased after
copper treatment in both cultivars, while they were higher in ‘Wutacai’ than in ‘Erqing’, which may explain the higher copper-tolerance
of ‘Wutacai’ with higher copper accumulation. The higher AsA contents of ‘Wutacai’ resulted from their lower activities of
degrading enzymes, such as ascorbate oxydase (AAO) and ascorbate peroxidase (APX), as well as the increasing activity of dehydroascorbate
reductase (DHAR) after copper treatment compared with ‘Erqing’. Copper stimulated superoxide dismutase (SOD) activity in both
cultivars, but for catalase (CAT), there was little difference between both cultivars. Peroxidases (POD) activity was decreased
after copper treatment in ‘Erqing’, while in ‘Wutacai’, it was significantly increased at 14 days, and POD activity was higher
in ‘Wutacai’ than that in ‘Erqing’ at 21 and 28 days. Therefore, the induced increasing activity of POD in ‘Wutacai’ also
played an important role in its copper tolerance. 相似文献
10.
Alicia S. Molina Carlos Nievas María Verónica Pérez Chaca Francisco Garibotto Ulises González Silvana M. Marsá Celina Luna María Sofía Giménez Fanny Zirulnik 《Plant Growth Regulation》2008,56(3):285-295
Cadmium (Cd)-induced oxidative stress and antioxidant defense mechanisms were analyzed in roots and leaves of Vigna mungo L. Seeds were germinated in perlite-vermiculite and irrigated with Hoagland nutrient solution. At day 6, seedlings were exposed
to 40 μM Cd under semi-hydroponic conditions for a period of 12 days. Growth anomalies and abnormal chromatin condensation
were observed in Cd-treated plants, in comparison with control ones. Cd accumulation was observed in roots of treated plants.
The analyses of antioxidative defense and oxidative parameters in roots, stems and leaves showed different tissue-specific
responses. Superoxide dismutase (SOD) and guaiacol peroxidase (GPx) activities and the level of lipid peroxidation (MDA content)
decreased in roots. However, they increased in leaves. Catalase activity and chlorophyll content, on the other hand, decreased
over exposure to Cd stress. Total glutathione, non-protein thiols, reduced glutathione (GSH) and phytochelatins increased
significantly, while oxidized glutathione (GSSG) decreased, as compared with control plants. The present data suggest that
the presence of Cd in soil and water can cause oxidative damage that may be detrimental for optimum production of nutritional
mung. 相似文献
11.
Comparative study about the salt-induced oxidative stress and lipid composition has been realised in primary root tissues
for two varieties of maize (Zea mays L.) in order to evaluate their responses to salt stress. The root growth, root water content (WC), hydrogen peroxide (H2O2) generation, lipid peroxidation, membrane stability index and the changes in the profile of fatty acids composition were
investigated. Salinity impacts in term of root growth, water content, H2O2 generation, lipid peroxidation and membrane destabilisation were more pronounced in primary roots of Aristo than in those of Arper indicating more sensitivity of the first variety. It was confirmed by gas chromatography that the composition of fatty acids
in roots of both varieties was constituted mainly by 16:0 and 18:0 as major saturated fatty acids and 18:1ω9, 18:2ω6 and 18:3ω3
as major unsaturated fatty acids. Total lipid extracts from the roots of both varieties showed that the lipid saturation level
increased under salt stress, notwithstanding the increased proportion of polyunsaturated fatty acids. The changes in lipid
saturation being predominantly due to decreases in oleic acid (18:1ω9) and increases in palmitic acid (16:0). However, Arper root extracts contained a lower proportion of saturated lipids than Aristo. The enhanced proportion of highly polyunsaturated fatty acids especially linolenic and eicosapentaenoic acids was considered
to be the characteristic of the relatively salt tolerance in Arper roots. 相似文献
12.
The effect of calcium (Ca2+) on Trifolium repens L. seedlings subjected to cadmium (Cd2+) stress was studied by investigating plant growth and changes in activity of antioxidative enzymes. Physiological analysis
was carried out on seedlings cultured for 2 weeks on half-strength Hoagland medium with Cd2+ concentrations of 0, 400 and 600 μM, and on corresponding medium supplied with CaCl2 (5 mM). Exposure to increasing Cd2+ reduced the fresh weight of the upper part (stems + leaves) of the seedlings more strongly than that of the root system.
In both parts of T. repens seedlings H2O2 level and lipid peroxidation increased. In the upper part, Cd2+ exposure led to a significant decrease in the activity of superoxide dismutase, catalase and glutathione peroxidase and an
increase in ascorbate peroxidase activity. In contrast, the roots showed an increase in the activity of antioxidative enzymes
under Cd2+ stress. Ca2+ addition to medium reduced the Cd2+ accumulation, and considerably reversed the Cd2+-induced decrease in fresh mass as well as the changes in lipid peroxidation in the both parts of T. repens seedlings. Ca2+ application diminished the Cd2+ effect on the activity of antioxidative enzymes in the upper part, even though it did not significantly affect these enzymes
in the roots. So the possible mechanisms for the action of Ca2+ in Cd2+ stress were considered to reduce Cd2+ accumulation, alleviate lipid peroxidation and promote activity of antioxidative enzymes. 相似文献
13.
14.
X. L. Zhao W. Ma K. R. Gale Z. S. Lei Z. H. He Q. X. Sun X. C. Xia 《Molecular breeding : new strategies in plant improvement》2007,20(3):223-231
Low-molecular-weight glutenin subunits (LMW-GS) have great effect on wheat processing quality, but were numerous and difficult
to dissect by SDS-PAGE. The development of functional markers may be the most effective way for a clear discrimination of
different LMW-GS genes. In the present study, three different approaches were used to identify SNPs of different genes at
Glu-D3 and Glu-B3 loci in bread wheat for the development of six STS markers (3 for Glu-D3 and 3 for Glu-B3 genes) that were validated with distinguished wheat cultivars. Firstly, seven LMW-GS gene sequences (
AY585350, AY585354, AY585355, AY585356, AY585349, AY585351 and AY585353
) from Aegilops tauschii, the diploid donor of the D-genome of bread wheat, were chosen to design seven pairs of AS-PCR primers for Glu-D3 genes. By amplifying the corresponding genes from five bread wheat cultivars with different Glu-D3 alleles (a, b, c, d and e) and Ae. tauschii, a primer set, S13F2/S13R1, specific to the gene AY585356, was found to be positive to cultivars with alleles Glu-D3c and d. Nevertheless, the other five pairs of primers designed from AY585350, AY585349, AY585353, AY585354 and AY585355, respectively, did not produce specific PCR products to the cultivars tested. Secondly, all the PCR products from the five
primer sets without specific characteristics were sequenced and an SNP from the gene AY585350 was detected in the cultivar Hartog, which resulted in the second STS marker S1F1/S1R3 specific to the allelic variant of AY585350. Thirdly, three Glu-D3 sequences (AB062851, AB062865 and AB062872) and three Glu-B3 sequences (AB062852, AB062853 and AB062860) defined by Ikeda et al. (2002) were chosen to query wheat EST and NR databases, and DNA markers were developed based on the putative SNPs among the sequences.
Using this approach, four STS markers were developed and validated with 16-19 bread wheat cultivars. The primer set T1F4/T1R1 was also a Glu-D3 gene-specific marker for AB062872, while T2F2/T2R2, T5F3/T5R1 and T13F4/T13R3 were all Glu-B3 gene specific markers for AB062852, BF293671 and AY831800, respectively. The chromosomal locations of the six markers were verified by amplifying the genomic DNA of Ae. tauschii (DD), T. monococcum (AA) and T. turgidum (AABB) entries, as well as Chinese Spring and its group 1 chromosome nulli-tetrasomic lines. The results are useful to discriminate
the corresponding Glu-D3 and Glu-B3 genes in wheat breeding programs. 相似文献
15.
Mirta Tkalec Tatjana Prebeg Vibor Roje Branka Pevalek-Kozlina Nikola Ljubešić 《Acta Physiologiae Plantarum》2008,30(6):881-890
Although duckweed Lemna minor L. is a known accumulator of cadmium, detailed studies on its physiological and/or defense responses to this metal are still
lacking. In this study, the effects of 10 μM CdCl2 on Lemna minor were monitored after 6 and 12 days of treatment, while growth was estimated every 2 days. Cadmium treatment resulted in progressive
accumulation of the metal in the plants and led to a decrease in the growth rate to 54% of the control value. The metal also
considerably impaired chloroplast ultrastructure and caused a significant reduction in pigment content, i.e., at day 12, by
30 and 34% for chlorophylls a and b, and by 25% for carotenoids. During cadmium treatment, the contents of malondialdehyde and endogenous H2O2 progressively increased (rising 77 and 46% above the controls by day 12), indicating that cadmium induced considerable oxidative
stress. On the other hand, higher activities of pyrogallol peroxidase (PPX), ascorbate peroxidase (APX) and catalase (CAT),
as well as the induction of a new APX isoform, in cadmium-treated plants, clearly showed activation of an antioxidative response.
At day 6, only PPX activity was significantly above the controls (15%), while, at day 12, PPX, APX and CAT activities were
increased (74, 78 and 63%). Cadmium also led to accumulation of the heat shock protein 70 (HSP70) and induced an additional
isoform of this protein. The obtained results suggest that cadmium (10 μM) is phytotoxic to Lemna minor, inducing oxidative stress, and that antioxidative enzymes and HSP70 play important roles in the defense against cadmium
toxicity.
M. Tkalec and T. Prebeg contributed equally to this work 相似文献
16.
A. V. Loskutov G.-Q. Song K. C. Sink 《In vitro cellular & developmental biology. Plant》2008,44(4):239-245
Callus selection (CS) and the flamingo-bill explant (FB) methods were evaluated for efficacy in transformation for celery.
Agrobacterium tumefaciens strains EHA105 and GV3101, each with the bar gene under the promoters NOS (pGPTV-BAR) or 35S (pDHB321.1), were used. Leaf explants were inoculated and co-cultivated for
2 d in the dark. Calluses emerged on the explants on callus medium (C), Murashige and Skoog (MS) medium + 2,4-Dichlorophenoxyacetic
acid (2,4-D) (2.3 μM) + kinetin (2.8 μM) + timentin (300 mg·l−1). Calluses 4- to 6-wk-old were selected for glufosinate (GS) resistance by a two step method. First, calluses were transferred
to C medium + GS 0.35, 0.5, 1, 2, 5, or 10 mg·l−1; calluses formed only with 0, 0.35 and 0.5 mg·l−1 GS. All growing calluses from 0 and 0.35 mg·l−1 and a few from 0.5 mg·l−1, were divided and placed back on C + GS 0.35–0.5 mg·l−1 for another 5–6 wk. Second, tolerant clones were again divided and placed on C + GS 1–50 mg·l−1. When cultivar XP85 was inoculated with both strains, using pGPTVBAR, 19 glufosinate resistant (GR) callus clones were selected,
but shoots regenerated only for strain EHA105 inoculations. When both of the strains (each with pDHB321.1) were inoculated
on cv. XP166, 3 and 12 GR calluses occurred for EHA105 and GV3101, respectively. Using CS, a total of 34 GR callus clones
were selected, and shoots were regenerated from over 50% of them on Gamborg B5 medium + 6-(γ, γ-dimethylallylamino) purine
2ip (4.9 μM) + naphthaleneacetic acid (NAA; 1.6 μM) and rooted on MS in 5–6 mo total time. Conversely, using FB with inoculation
by GV3101/pDHB321.1 on cv. XP166 yielded putative transgenic celery plants confirmed by polymerase chain reaction (PCR) in
just 6 wk. Transformation of the bar gene into celery was confirmed by PCR for 5 and 6 CS and FB lines, respectively. Southern blot analyses indicated 1–2 copies
in CS lines and 1 copy in FB lines. Herbicide assays on whole plants with 100 and 300 mg·l−1 glufosinate indicated a range of low to high tolerance for lines derived by both methods. The bar gene was found to be Mendelian inherited in one self-fertile CS derived line. 相似文献
17.
In Arabidopsis, NPR1 (non-expressor of pathogenesis related genes 1, AtNPR1) functions downstream of salicylic acid (SA) and modulates the SA mediated systemic acquired resistance. It is also involved
in a cross talk with the jasmonate pathway that is essential for resistance against herbivores and necrotrophic pathogens.
Overexpression of AtNPR1 in transgenic plants resulted in enhanced disease resistance. Recently, tobacco transgenic plants expressing AtNPR1 were shown to be tolerant to the early instars of Spodoptera litura (Meur et al., Physiol Plant 133:765–775, 2008). In this communication, we show that the heterologous expression of AtNPR1 in tobacco has also enhanced the oxidative stress tolerance. The transgenic plants exhibited enhanced tolerance to the treatment
with methyl viologen. This tolerance was associated with the constitutive upregulation of PR1, PR2 (glucanase), PR5 (thaumatin like protein), ascorbate peroxidase (APX) and Cu2+/Zn2+ superoxide dismutase (SOD). This is the first demonstration of the novel function of heterologous expression of AtNPR1 in oxidative stress tolerance in transgenic tobacco. 相似文献
18.
The mechanisms that reduce the viability of plant somatic embryos following cryopreservation are not known. The objective
of the present study was to evaluate the sensitivity of cocoa (Theobroma cacao L.) somatic embryos at different stages of an encapsulation–dehydration protocol using stress-related volatile hydrocarbons
as markers of injury and recovery. The plant stress hormone ethylene and volatile hydrocarbons derived from hydroxyl radicals
(methane) and lipid peroxidation (ethane) were determined using gas chromatography headspace analysis. Ethylene and methane
were the only volatiles detected, with both being produced after each step of the cryogenic protocol. Ethylene production
was significantly reduced following exposure to liquid nitrogen, but then increased in parallel with embryo recovery. In contrast,
the production of methane was cyclic during recovery, with the first cycle occurring earlier for embryos recovered from liquid
nitrogen and desiccation than those recovered from earlier steps in the protocol. These results suggest that loss of somatic
embryo viability during cryopreservation may be related to the oxidative status of the tissue, and its capacity to produce
ethylene. This study has demonstrated that headspace volatile analysis provides a robust non-destructive analytical approach
for assessing the survival and recovery of plant somatic embryos following cryopreservation. 相似文献
19.
AnAgrobacterium-mediated gene transfer system with recovery of putative transformants was developed for cotton (Gossypium hirsutum L.) cv. Cocker-312. Two-month-old hypocotyl-derived embryogenic calli were infected through agroinfiltration for 10 min at
27 psi in a suspension ofAgrobacterium tumefaciens strain GV3101 carrying tDNA with theGUS gene, encoding β-glucuronidase (GUS), and the neomycin phosphotransferase II (nptII) gene as a kanamycin-resistant plant-selectable marker. Six days after the histochemicalGUS assay was done, 46.6% and 20%GUS activity was noted with the vacuum-infiltration and commonAgrobacterium-mediated transformation methods, respectively. The transformed embryogenic calli were cultured on selection medium (100 mg/L
and 50 mg/L kanamycin for 2 wk and 10 wk, respectively) for 3 mo. The putative transgenic plants were developed via somatic
embryogenesis (25 mg/L kanamycin). In 4 independent experiments, up to 28.23% transformation efficiency was achieved. PCR
amplification and Southern blot analysis fo the transformants were used to confirm the integration of the transgenes. Thus
far, this is the only procedure available for cotton that can successfully be used to generate cotton transformants. 相似文献
20.
NADP-malic enzyme (NADP-ME, EC 1.1.1.40) functions in many different pathways in plant and may be involved in plant defense
such as wound and UV-B radiation. Here, expression of the gene encoding cytosolic NADP-ME (cytoNADP-ME, GenBank Accession No. AY444338) in rice (Oryza sativa L.) seedlings was induced by salt stress (NaCl). NADP-ME activities in leaves and roots of rice also increased in response
to NaCl. Transgenic Arabidopsis plants over-expressing rice cytoNADP-ME had a greater salt tolerance at the seedling stage than wild-type plants in MS medium-supplemented with different levels
of NaCl. Cytosolic NADPH/NADP+ concentration ratio of transgenic plants was higher than those of wild-type plants. These results suggest that rice cytoNADP-ME confers salt tolerance in transgenic Arabidopsis seedlings. 相似文献