共查询到20条相似文献，搜索用时 312 毫秒
1.
AIM: To investigate the effect of peroxisome proliferator-activated receptor γ(PPARγ) on the invasion ability of trophoblasts. METHODS: A segment of PPARγ siRNA was synthesized. Three groups were designed: experiment group, negative control group and blank control group. The PPARγ siRNA was transfected into JEG-3 cells. Real-time quantitive PCR was used to detect the mRNA levels of PPARγ and mucin-1(MUC1). The Transwell culture inserts were used to detect the invasion ability of JEG-3 cells 24 h after treated with PPARγ siRNA. RESULTS: After transfected with PPARγ siRNA, the mRNA expression levels of PPARγ and MUC1 were significantly depressed by (75.0±0.8)% and (65.0±1.3)% (P<0.05),respectively, and the invasion ability of JEG-3 cells was significantly strengthened (P<0.05). CONCLUSION: The depression of PPARγ gene down-regulates the expression of MUC1, and affects the invasion ability of trophoblasts, indicating that PPARγ may regulate the invasion of trophoblasts by MUC1 and involve in the development of placental defects such as preeclampsia. 相似文献
2.
AIM: To study the senescence of human umbilical vein endothelial cells (HUVECs) and Bcl-2, Bax gene expression associated with apoptosis induced by angiotensinⅡ (AngⅡ).METHODS: HUVECs were cultured in vitro and the cell viability was observed by methyl thiazolyl tetrazolium (MTT). HUVECs were intervened by AngⅡ and valsartan (AngⅡ type 1 receptor blocking) and divided into 3 groups: the control group, AngⅡ group (stimulated with AngⅡ10-6mol/L for 48 h), valsartan group (valsartan was added to cells 1 h before 10-6mol/L AngⅡ treatment). β-gal staining and cell cycle analysis were used to identify the cell aging status. Morphologic changes and percentage of apoptosis were assayed with Hoechst33258 under fluorescent microscope. The expressions of Bcl-2 and Bax, and the apoptosis-associated genes were detected by immunocytochemical staining, RT-PCR and Western blotting. RESULTS: The cell viability by AngⅡ-induced cells was (81.9%±4.1)%, the positive cell number of β-gal staining was significantly higher in AngⅡ-induced cells (80.10%±6.81)% than that in the control cells. The cell cycle was at G0-G1(91.36%±6.45)%, the apoptotic cells significantly increased (31.84±2.86)% under fluorescent microscope. In valsartan group, Bcl-2 mRNA and protein expression increased markedly (P<0.05), but Bax mRNA and protein expression decreased evidently (P<0.05) compared to those in the AngⅡ group.CONCLUSION: Cell apoptosis is possibly an important factor for endothelial cell senescence and vascular aging induced by AngⅡ. One of its molecular mechanisms might be associated with decreasing the expression level of Bcl-2 and increasing that of Bax, which regulate the imbalance between mRNA and protein expression of Bcl-2 and Bax. Valsartan improves endothelial cell aging. 相似文献
3.
4.
AIM:To investigate the effect of over-expression of angiotensin-converting enzyme 2 (ACE2) gene on angiotensin Ⅱ (Ang Ⅱ)-induced oxidative stress and NADPH oxidase (NOX) expression in mouse neuroblastoma Neuro-2A cells. METHODS:The recombinant lentivirus encoding ACE2 gene was constructed and transfected into the Neuro-2A cells at a multiplicity of infection (MOI) of 10 for 72 h. The transfection efficiency of ACE2 gene and protein expression of ACE2 were detected, and the Neuro-2A cells were identified by detection of a neural cell marker. The Neuro-2A cells were divided into 7 groups:control group, eGFP group, ACE2-eGFP group, Ang Ⅱ treatment group, Ang Ⅱ-eGFP group, Ang Ⅱ-ACE2-eGFP group and Ang Ⅱ-ACE2-eGFP-A779 group. The Ang(1-7) level was determined by ELISA. The level of reactive oxygen species (ROS) in the cells was measured with a method of DHE staining. The protein expression of MAS receptor and NOX subunits (NOX2, NOX4, p47phox and p67phox) was detected by Western blot. RESULTS:Ang Ⅱ signi-ficantly increased ROS levels (P<0.01) and up-regulated the protein expression of NOX2, NOX4, p47phox and p67phox (P<0.01), but down-regulated MAS protein expression (P<0.01). Over-expression of ACE2 inhibited Ang Ⅱ-induced increase in ROS, down-regulated the protein expression of NOX2, NOX4, p47phox and p67phox,and still increased the Ang(1-7) level (P<0.01) and MAS receptor expression (P<0.01). An antagonist of the MAS receptor, A779, blocked the down-regulating effect of ACE2 on NOX expression (P<0.05). CONCLUSION:ACE2 over-expression antagonizes Ang Ⅱ-induced oxidative stress via MAS receptor in the neural cells. 相似文献
5.
AIM: To evaluate the effect of gene delivery plasmid encoding interleukin-1 receptor Ⅱ (IL-1RⅡ) for treating rat experimental autoimmune myocarditis (EAM). METHODS: Cardiac myosin was emulsified with equal volume of complete Freund's adjuvant, and EAM model was produced by injection with the preparation in both footpads of Lewis rats. The rats were immunized on day 0 and were injected with plasmid encoding IL-1RⅡ by hydrodynamics-based gene delivery on day 6. The expression of IL-1RⅡ on day 7, day 12 and day 17 was determined by Western blotting. Echocardiography was performed on day 16 and the rats were sacrificed on day 17. The effect of IL-1RⅡ gene therapy was evaluated by the ratio of heart weight/body weight, histopathological scores, relative expression of brain natriuretic peptide (BNP) in hearts and the echocardiographic parameters. The expression levels of IL-1-related cytokines, including IL-1β, prostaglandin E2 synthase (PGES) and monocyte chemotactic protein-1 (MCP-1) were also detected. RESULTS: The expression of IL-1RⅡincreased on day 7 after hydrodynamics-based gene delivery and maintained at high level until day 17. The rats in control group showed significant myocardial damage and a decrease in the left ventricular functions. The rats in the treatment group injected with IL-1RⅡ plasmid showed an improvement of the cardiac functions. The ratio of heart weight/body weight, the histopathological scores and the level of BNP were significantly lower in treatment group than those in control group. The expression of IL-1β, PGES and MCP-1 at mRNA and protein levels was also significantly inhibited in IL-1RⅡ treatment group. CONCLUSION: Hydrodynamics-based gene delivery plasmid encoding IL-1RⅡ effectively prevents the progression of the left ventricular remodeling and myocardial damage in rat EAM. 相似文献
6.
B. N. Krath F. D. Eriksen B. H. Pedersen L. J. W. J. Gilissen W. E. Van De Weg L. O. Dragsted 《The Journal of Horticultural Science and Biotechnology》2013,88(6):52-57
SummaryMany people who are allergic to birch pollen are also allergic to apple fruit, due to cross- allergenicity. Since apples are the most extensively consumed fruit in Europe, it is highly relevant to develop a hypo-allergenic apple.Apples with significantly reduced levels of the allergen, Mal d 1, may allow many apple allergics to eat them without an allergic reaction. We are currently collaborating to develop a hypo-allergenic apple within the European Integrated Research Project, ISAFRUIT (www.isafruit.org). Hypo-allergenic apple plants (Malus × domestica Borkh., ‘Elstar’) with decreased levels of Mal d 1 mRNA were produced by RNA interference (RNAi) technology. Ten genetically modified (GM) apple lines were selected. In vitro plantlets were first transferred to a greenhouse, then grafted onto wild-type M.9 rootstock to promote the development of fruit-producing trees. Levels of Mal d 1 gene silencing were measured repeatedly by quantitative real-time PCR. Compared to leaf samples from wild-type ‘Elstar’, two GM lines showed modest levels of gene silencing (up to 250-fold), whereas the other eight GM lines were significantly silenced (up to10,000-fold) in Mal d 1 gene expression. These levels of silencing were unaffected by grafting, and have been stable over more than 3 years, and throughout all developmental stages. 相似文献
7.
【Objective】The purpose of the research was to study the occurrence and molecular diversity of Actinidia virus A (AcVA), so as to provide scientific basis for the rapid detection, scientific prevention and control of AcVA and the variety breeding of kiwifruit in China.【Methods】Total RNA was extracted from kiwifruit leaves by CTAB (Cetyl Trimethyl Ammonium Bromide). Nested- PCR was used to amplify AcVA CP gene sequence. The first round PCR amplification was performed by using primers AcVA- 1F (5’- ATGAATCGTTCGAGCA TAGGT- 3’) and AcVA- 1R (5’- TGCGAACATGGTCCCACACTTA-3’), and the pair of primers was designed according to the full length of AcVA sequence, and the amplified fragment was 888 bp that included the complete CP gene sequence. The reaction was conducted under conditions of initial 5 min denaturation at 94 ℃, 34 cycles of 94 ℃ for 60 s, 54 ℃ for 60 s, 72 ℃ for 60 s and extension for 10 min at 72 ℃. Then, 1 μL PCR product was used as template for the second round of PCR amplification with the primers AcVA- 2F (5’- ATGGCAAAGAATATCTCAAG-3’) and AcVA-2R (5’-CTATATTTCAACAGCCTGC-3’). PCR was performed using the following parameters: one cycle at 94 ℃ for 5 min, 34 cycles at 94 ℃ for 30 s, 54 ℃ for 30 s, and 72 ℃ for 40 s, and extension for 10 min at 72 ℃. The BLAST algorithm was used to search the NCBI GenBank (http://www.ncbi.nlm.nih.gov/) databases for homologous sequences and ascertain the identity of target gene. DNAMAN was used to analyze the AcVA CP gene sequence, and MegAlign was used to analyze the sequence identity. The phylogenetic tree was constructed using the Neighbor-Joining (NJ) method in MEGA 6.0. The restriction enzymes Bam HⅠ and Sal Ⅰ were added to the corresponding end of the AcVA CP gene sequence, respectively. The PCR purified products and pET28a vector were digested by Bam HⅠ and Sal Ⅰ, after that they were ligated with T4 DNA ligase (TaKaRa) and transferred into E. coli (Escherichia coli) strains DH5á (TaKaRa), and finally plated onto LB (Luria-Bertani) agar containing Kana (Kanamycin). The expression strain BL21 containing the recombinant plasmid was cultured at 37 ℃ overnight, and transferred to a new medium at a 10% inoculum on the second day, until OD600 reached 0.4-0.6, IPTG (Isopropyl β-D-Thiogalactoside) was added to a final concentration of 0.2, 0.4, 0.6, 0.8, 1.0 mM, and incubated at 16 ℃ overnight. The expressed protein was purified and then anti-AcVA-CP antibody was obtained from a rabbit. The optimal titer of the antiserum was tested by Western blot.【Results】The complete CP gene sequences of AcVA Sichuan isolates were cloned by nested-PCR and named as AcVA-DJY4, AcVA-HYZ1 and AcVA-WBS12, respectively. In the study the frequency of AcVA in Sichuan province was also counted. The full length of the CP gene sequence was 597 bp, encoding 198 amino acids. Based on the comparison of the nucleotide sequence and the deduced amino acid sequence of CP gene of the AcVA isolates, the nucleotide identity between the AcVA isolates from Sichuan province ranged from 86.9% to 88.3%, and the identity of the encoded amino acids ranged from 96.0 to 96.5%. The CP genes of three AcVA Sichuan isolates shared 87.9%-90.8% nucleotide identity and 94.9%-97.5% amino acid identity with the Actinidia virus A isolate TP7-93A (AcVA-TP7-93A) from New Zealand and the Actinidia virus A isolate Haenam (AcVA-Haenam) from South Korea. Phylogenetic analysis based on nucleotide sequence of AcVA CP gene showed that AcVA-HYZ1 was clustered with AcVA-Haenam (Group I), and AcVA-WBS12 was clustered with AcVA-TP7-93A (Group II), but AcVA-DJY4 was an independent branch. Phylogenetic analysis based on amino acid sequence of AcVA CP gene showed that AcVA-WBS12 was a single branch, AcVA-DJY4 and AcVA-HYZ1 were clustered into one group (Group I), and the AcVA-Haenam reported in South Korea and the AcVA-TP7-93A reported in New Zealand were clustered into another group (Group II). The results of the phylogenetic analyses indicated that there were significant differences among the AcVA isolates. The prokaryotic expression plasmid pET28a-AcVA-DJY4-CP was successfully constructed. The target fusion protein (27 kDa) was highly expressed in E. coli induced by 0.6 mmol · L- 1 IPTG at 16 ℃. The expressed protein was purified and retrieved and then used to immune rabbits and the corresponding specific antiserum was prepared. Western blot analysis confirmed that the antiserum reacted strongly and specifically with the CP of AcVA-DJY4, with the optimal titer of the antiserum being up to 1:5 000.【Conclusion】Three AcVA Sichuan isolates were obtained for the first time, enriching the sequence diversity of the AcVA CP gene sequences. In the study, the optimal conditions were explored for prokaryotic expression and specific antisera was prepared for detection of AcVA-DJY4-CP. Western blot analysis showed that the antiserum could be used for the detection of AcVA in the kiwifruit producing districts. These results can also provide a technical support for the rapid detection, scientific prevention and control of virus disease in kiwifruit plant and the breeding of kiwifruit varieties. © 2019 Journal of Fruit Science 相似文献
8.
9.
LI Dong-ye YAN Yan ZHU Hong XIA Yong LIU Yi-na LIU Chuang PAN De-feng YANG Yu 《园艺学报》2008,24(2):275-278
AIM:To determine the effects of adenovirus mediated hypoxia-inducible factor-1α(HIF-1α) gene on myocyte apoptosis and cardiac function after acute myocardial infarction (AMI) of rabbits.METHODS:Rabbits were made AMI model, divided into 4 groups at random and infected with Ad-HIF-1α, Ad-blank or Rz-HIF-1α, respectively. Sham group was served as control. The cardiac functions of rabbits at different time points were detected by Maclab/8s. Myocyte apoptosis was detected with TUNEL method at different time points.RESULTS:Apoptotic cells were the highest in Rz-HIF-1α treated group, less in Ad-HIF-1α treated group than that in Ad-blank group. Apoptotic cells decreased with extension of time and were found at the time of 56 d. The cardiac function parameters were the highest in sham, lowest in Rz-HIF-1α, and were higher in Ad-HIF-1α than those in Ad-blank.CONCLUSION:Myocyte apoptosis is inhibited by Ad-HIF-1α, increased by Rz-HIF-1α. The cardiac function is improved by Ad-HIF-1α, deteriorated by Rz-HIF-1α. 相似文献
10.
AIM: To study the distribution of C46T polymorphism of factor Ⅻ(FⅫ) in Chinese Han population and the association of the polymorphism with coronary artery disease(CAD) and acute coronary syndrome(ACS). METHODS: Selected coronary angiography was performed in 168 CAD patients and 210 controls. Genetype of FⅫ was typed by mutagenically separated polymerase chain reaction assay(MSPCR). RESULTS: FⅫ allelic frequencies of C and T were 29.8%, 70.2% and 31.4%, 68.6% in CAD and controls, respectively(P>0.05). Genetype distribution was in accordance with Hardy-Weinberg equilibrium. The frequency of CC, CT, TT in CAD and control was 8.7%, 40.5%, 50.0% and 5.2%, 52.6%, 42.2%. The association between FⅫ genetype and CAD(2=6.393, P<0.05) was observed. As compared with the CC group, the CT genetype was a protective factor for CAD(OR 0.43, 95% CI 0.19-0.97). When compared to stable coronary artery disease, the frequency of TT genetype is significant less in ACS group(45.0% vs 62.5%, 2=4.200, P<0.05). The distribution of genetype in C46T was no significant difference among the numbers of stenosed coronary artery. CONCLUSION: The C46T polymorphism of FⅫ is association with CAD in Chinese Han population. The C→T mutation may be a protective factor against CAD and ACS. 相似文献
11.
AIM: To investigate the gene polymorphisms of interferon-γ(IFN-γ) and interleukin-4(IL-4) and the association with asthmatic susceptibility and the levels of plasma IFN-γ, IL-4 and IgE of asthmatic children. METHODS: 100 asthmatic children and 122 control children were enrolled the study. The genotypes of IFN-γ gene-179G/T polymorphism, IL-4 gene-33C/T and-589C/T polymorphisms were tested by PCR-RFLP.The genotype of IFN-γ gene +874A/T polymorphism was tested by AS-PCR.The CA repeat polymorphism of IFN-γ gene was detected by capillary electrophoresis technique.The levels of serum IFN-γ, IL-4 and IgE were measured by ELISA. RESULTS: 100 asthmatic children and 122 control children were all GG homozygotes at -179 locus of IFN-γ gene.-179 locus of IFN-γ gene has no mutation. The genotypes and allele frequency of IFN-γ gene +874A/T and CA repeat polymorphisms showed no significant difference between asthmatic children and the control(P>0.05). An association was revealed between IFN-γ gene +874A/T polymorphism and the level of plasma IFN-γ.The level of IFN-γ was lower in AA genotype than in AT genotype(P<0.05). The genotypes and allele frequency of IL-4 gene -33C/T and -589C/T polymorphisms showed significant difference between asthmatic children and the control(P<0.05).The levels of plasma IL-4 and IgE were higher in TT genotype at -33 locus and -589 locus than those in CT genotype, but only -33C/T polymorphism was associated with the level of plasma IL-4(P<0.05). CONCLUSION: The IFN-γ gene +874A/T and CA repeat polymorphisms were not correlated with asthmatic susceptibility, but there is significant correlation between the level of IFN-γ and +874A/T polymorphism. TT genotype of IL-4 gene -33 locus and -589 locus maybe the susceptible genotype of asthma in children, and the -33 locus polymorphism is associated with the level of IL-4. 相似文献
12.
S. K. Kang C. S. Jang H. Y. Kim S. H. Yun H. J. An J. H. Park 《The Journal of Horticultural Science and Biotechnology》2013,88(5):742-747
SummaryCalamondin (× Citrofortunella mitis J. Ingram & H. E. Moore) is known for its ability to develop floral organs to flower in the adult phase during the four seasons. To provide information on molecular events during floral differentiation from axillary buds, we constructed a cDNA library from floral differentiating axillary buds of adult phase calamondin. Ninety-six cDNA clones were randomly selected from this library and sequenced. Ninety-six nonredundant ESTs were identified. Two clones encoded S-adenosylmethione decarboxylase, a key enzymes in polyamine biosynthesis. CmSAMDC 1 (Citrofortunella mitis s-adenosylmethionine decarboxylase 1) contained an 1083 bp ORF that encoded a putative SAMDC precursor of 361 amino acids. Northern blot analysis revealed that CmSAMDC 1 was expressed in axillary buds prior to floral differentiation and in axillary buds immediately after floral differentiation, in immature flower (5 mm), in fully developed flowers (120 mm long), in floral parts (petals, pistils, and stamens) of trees in the adult phase of development, but not in leaves or axillary buds of juvenile phase nucellar seedlings or leaf tissue from trees in adult phase of development. In situ hybridization revealed expression of the CmSAMDC 1 gene in the floral apex of axillary buds after differentiation, and in the phloem of axillary buds and petioles. These results suggest that SAMDC could play a role in actively differentiating and developing reproductive and vegetative organs. 相似文献
13.
14.
MA Hui-xiang XU Jin-tang JIANG Zhen-you ZHANG Sui-mei ZHAO Song-bin CHEN Jian-su 《园艺学报》2008,24(5):915-919
AIM: To investigate the effects of rhTGF-β1 and TGF-β1 gene transfection on the proliferation of cultured rabbit corneal endothelial cells in vitro. METHODS: Cell growth induced by various concentrations of rhTGF-β1 was determined by MTT proliferation assay. Under the induction of liposomes, recombinant pSecTag2-TGF-β1MP vectors were transferred into the corneal endothelial cells. Morphological changes of transfected cells were observed by HE staining. The expression levels of TGF-β1 were assessed by ELISA. Cell cycle analysis was assessed by flow cytometry. DNA fragment analysis was used to confirm the presence of apoptosis. RESULTS: rhTGF-β1 in concentrations of 5-20 μg/L showed a significant suppressive effect on the proliferation of corneal endothelial cells, 0.5-1 μg/L had no effect, 0.05-0.1 μg/L facilitated cell growth, as compared with negative controls. The morphous of transfected corneal cells had no significant abnormality compared with normal cells. According to the result of ELISA, the concentration of TGF-β1 in the supernatant was calculated to be (98±3) ng/L. Flow cytometry assay showed that S and G2/M phase of transfected cells decreased significantly compared with that of control group, but the cell cycle recovered normally after adding 10 μg/L EGF into the culture medium. Agarose electrophoresis didn′t show marked ladders in transfected group. CONCLUSION: Effects of rhTGF-β1 on the proliferation of corneal endothelial cells are different with various concentrations. TGF-β1 gene transfection shows suppressive effect on the proliferation of cultured corneal endothelial cells, but does not induce cell apoptosis. EGF is the antagonist of this suppressive effect. 相似文献
15.
W. Krongyut E. B. Esguerra J. S. Maninang S. Sugaya H. Gemma 《The Journal of Horticultural Science and Biotechnology》2013,88(6):631-639
SUMMARY‘Sunrise’ papaya fruit harvested at two stages of maturity [colour break (< 10% yellow peel colour) and 25% yellow peel colour] were treated with 100 nl l–1 1-methylcyclopropene (1-MCP) to determine its effects on ripening, on the activities and levels of gene expression of polygalacturonase (PG), pectin methyl esterase (PME), and βgalactosidase ( βGal), and on the degradation of cell wall components. 1-MCP delayed ripening and the onset of the climacteric, although the peak in the respiration rate was almost the same as that in untreated control fruit. Colour-break fruit treated with 1-MCP exhibited a continuous increase in ethylene production, but at a lower rate than in control fruit. Consequently, 1-MCP-treated fruit ripened with a concomitant reduction in firmness, which was accompanied by an increase in PG and βGal enzyme activities and gene expression. On the other hand, fruit treated with 1-MCP at the 25% yellow stage exhibited lower levels of ethylene production and developed pulp with a rubbery texture at the ripe stage which was attributed to reduced PG, βGal, and PME enzyme activities and gene expression. This was consistent with the higher level of cell wall polysaccharides measured in 1-MCP-treated fruit. The above results indicated that ‘Sunrise’ papaya fruit can be treated with 1-MCP at the colour break stage since they have a greater capacity to recover from the effects of 1-MCP than fruit treated at the 25% yellow stage. 相似文献
16.
SummaryPlasmid DNA (pARS108) containing the non-destructive selectable marker Green Fluorescent Protein (GFP) gene, and a plasmid containing a cDNA of the Xa21 gene from rice (pXa21-mtaq) were co-transformed into ‘Hamlin’ orange protoplasts using polyethylene glycol (PEG). Alternatively, plasmid DNA (pAO3), containing both genes (GFP and Xa21) was directly transformed into ‘Hamlin’ orange protoplasts. Over 1,000 transgenic plantlets were regenerated from approx. 80 independent transformation events. The transgenic plants showed normal growth and stable GFP expression over more than 2 years in the greenhouse. This is the first report of a large population of transgenic ‘Hamlin’ sweet orange plants containing one or more target gene(s), using a protoplast-GFP transformation system. Polymerase chain reaction (PCR) revealed the presence of the Xa21 cDNA and the GFP genes in all single plasmid transformed plants, and in 35% of the co-transformed plants. Southern blot analysis showed the integration of the cDNA into one-to-five different sites per plant.Western blot analysis showed the accumulation of the rice XA21 protein in the transgenic sweet orange plants. This is the first time that a gene from rice has been stably integrated and expressed in sweet orange plants. Using the protoplast-GFP transformation system, it is possible to avoid the use of Agrobacterium, antibiotic resistance genes, and destructive assay systems. 相似文献
17.
18.
When apples which develop low temperature breakdown (LTB) at 32° F. are moved from 32° F. to 65° F. for 3 to 5 days at about the 7th to 8th week of storage, they subsequently develop within a given period of storage less LTB than apples kept at 32° F. continuously.The respiration of apples susceptible to LTB increases steadily during storage at 32° F. If these apples are warmed to 65° F. during the period of exposure to 32° F., the subsequent rate of respiration at 32° F. is lower than before warming, and continues at a lower rate than for apples kept at 32° F. continuously.If the apples are moved to 38° F., without an intermediate treatment at 65° F., the rate of respiration is higher than for apples at 38° F. continuously, and this higher rate persists.If there is an intermediate wanning period at 65° F., the respiration of apples moved from 32° to 38° F. is of the same order as that for apples kept at 38° F. continuously.The respiratory quotient of apples at 32° F. or at 38° F., which is indicative of the type of respiratory activity, is typical for the temperature at which it is measured, and is not affected by the warming treatment. The effects of wanning on both the incidence of LTB and respiration are similar for apples stored in air and in 2% oxygen: 98% nitrogen. 相似文献
19.
G. Marino G. Marcolini M. Toselli 《The Journal of Horticultural Science and Biotechnology》2013,88(6):1015-1020
SummaryThe present work investigated the effects of different aqueous extracts of organic waste compounds on growth, proliferation and photosynthetic activity in ‘M9’ (Malus domestica Borkh.) shoot cultures, with the aim of determining the feasibility of using in vitro cultures as a tool for the rapid evaluation of organic amendments in agriculture. Aqueous extracts of the following organic waste compounds: cow manure (CM), sugarbeet industrial waste (SB), mixed grape, poultry and municipal solid waste (GPM), and citrus pruning and industrial waste (CPI) were prepared at a rate of 1:10 (w/v) compound:distilled water. The basal media used in the proliferation phase were: (i) PM1, modified Murashige and Skoog (MS) enriched with 4.4 µM 6-benzyladenine (BA); (ii) PM2, as PM1 but with a reduced cytokinin concentration (1 µM BA) to evaluate possible hormone effects; and (iii) PM3, 4.4 µM BA with reduced salt strength (0.33 MS) to induce nutrient deficiency. Hormone-free medium with half-strength MS salts was used for rooting. All media were enriched with each extract at 0, 0.2, 2, 20 or 200 ml l–1. Photosynthetic activity was measured on PM3 medium enriched with SB or CM. Standard culture conditions were 22° ± 2°C, with a 16 h photoperiod at 30 µmoles photosynthetically active radiation (PAR) m–2 s–1, but at 80 µmoles PAR m–2 s–1 to determine photosynthetic activity. Shoot weight increase in PM1 was not affected by the GPM and CPI extracts, while the growth trends of CM- and SB-treated shoots were described by a second-degree function with maxima at 2 ml l–1 and 0.2 ml l–1, respectively. Shoot proliferation for SB was represented by a quadratic curve (maximum at 2 ml l–1), was linearly reduced as GPM increased, but was not affected by CM or CPI. Treatments did not significantly affect rooting percentage and root length; however root number was increased by SB at 2 ml l–1.CO2 fixation increased linearly with both SB and CM, despite reduced growth at the highest levels of extract. 相似文献
20.
Sally A. Bound K. M. Jones B. Graham M. J. Oakford M. Tichon 《The Journal of Horticultural Science and Biotechnology》2013,88(6):967-973
A trial on ‘Fuji’ apples at the Grove Research Station in southern Tasmania during the 1991/92 season studied the thinning effect and interactions between ethephon and benzyladenine (BA) when BA was applied as a secondary thinner after a full bloom (FB) application of ethephon. The spray treatments were a factorial combination of eight application times of BA (11,13,15,17,19, 21, 23 or 25 days after full bloom (AFB)) with ten concentrations (20,40,60,80,100,120,140,160,180 or 200 mg I“1). An unsprayed control and an ethephon control were included. Target thinning results were achieved 19- 23 d AFB with concentrations of 140-160 mg I“1. A corollary of this successful thinning was an increase in fruit weight and size. Return bloom was improved significantly where thinning was successful. There was no effect on fruit firmness, soluble solids or lateral branching. Drawbacks were an increase in the incidence of russet and a reduction in pip number at the optimum thinning times and concentrations. 相似文献