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1.
本文详细报道了西瓜蔓枯病的症状和病原菌的形态特点,并鉴定其有性阶段为Mycosphaerellamelonis(Pass)Chiu et Walker,无性阶段为Ascochyta-cucumis Fautr et Roum.此外,还在其他瓜类作物上作了病原菌的致病性试验.  相似文献   
2.
朱秦  强胜 《中国生物防治》2004,20(2):122-126
将不同含水量的胶孢炭疽菌婆婆纳专化型菌株QZ 97a分生孢子粉置于4℃和室温下,密闭或开放贮存。结果表明,4℃下密闭贮藏6个月,分生孢子萌发率和芽管长度无明显降低,室温贮藏降低也不明显。贮藏10个月后,各种贮藏方式孢子的活力都显著下降。但以4℃、含水量4%、密闭贮藏孢子活力较为稳定,420d孢子萌发率为70 4%,芽管长度为贮藏60d时的43 2%。含水量9 6%、开放室温下贮藏的孢子粉活力下降最大。因此,温度和孢子粉含水量是影响孢子货架期的两个主要因素。分生孢子粉对温度有一定的耐受性,随温度增高,敏感性增强,60℃下分生孢子的活力下降显著,处理6min,孢子芽管长度较对照下降50%。  相似文献   
3.
4.
菊花花粉生活力及瓶插授粉研究   总被引:2,自引:0,他引:2  
为研究菊花花粉的生活力及其对室内瓶插杂交结实率的影响,用1%醋酸洋红染色法检测了10个菊花品种花粉的生活力。结果显示,菊花花粉生活力为70.8%~97.6%,不同品种间有一定的差异。同一个花序,外围管状花的花粉生活力比中心的高,而同一天内的花粉生活力随取样时间的不同也发生变化。花粉在4℃的冰箱内贮藏15 d后,花粉生活力平均降低了16.45个百分点。选取4个菊花品种间2个正反杂交组合进行室内瓶插授粉后,不同组合间结实率有很大差异。试验结果还表明,醋酸洋红染色法可以用来检测菊花花粉的生活力,菊花花粉生活力与杂交结实率并非简单的正相关关系。  相似文献   
5.
AIM To investigate the mechanism of long noncoding RNA (lncRNA) FEZF1-AS1 regulating microRNA-363-3p (miR-363-3p) on the viability and apoptosis of lipopolysaocharide (LPS)-induced vascular endothelial cells. METHODS Human umbilical vein endothelial cells (HUVECs) were cultured in vitro. pcDNA-NC, pcDNA-FEZF1-AS1, anti-miR-NC, anti-miR-363-3p, miR-NC and miR-363-3p mimics were transfected into the HUVECs and LPS stimulation was applied for 24 h. RT-qPCR was used to detect the expression of FEZF1-AS1 and miR-363-3p. The cell viability was measured by MTT assay. The apoptotic rate was analyzed by flow cytometry. The dual-luciferase reporter experiment was used to verify the targeted regulation of FEZF1-AS1 and miR-363-3p. Western blot was used to determined the expression of cyclin D1, Ki67 and cleaved caspase-3. RESULTS Compared with control group, the expression level of FEZF1-AS1 in LPS group was significantly reduced (P<0.05), and the expression level of miR-363-3p was significantly increased (P<0.05). Compared with pcDNA-NC+LPS group, the cell viability in pcDNA-FEZF1-AS1+LPS group was significantly increased (P<0.05), the apoptotic rate was significantly reduced (P<0.05), the protein levels of cyclin D1 and Ki67 were significantly increased (P<0.05), and the protein level of cleaved caspase-3 was significantly reduced (P<0.05). Compared with anti-miR-NC+LPS group, the cell viability in anti-miR-363-3p+LPS group was significantly increased (P<0.05), the apoptotic rate was significantly reduced (P<0.05), the protein levels of cyclin D1 and Ki67 were significantly increased (P<0.05), and the protein level of cleaved caspase-3 was significantly reduced (P<0.05). Dual-luciferase reporter experiment confirmed that FEZF1-AS1 targeted miR-363-3p. Compared with miR-NC+pcDNA-FEZF1-AS1+LPS group, the cell viability in miR-363-3p+pcDNA-FEZF1-AS1+LPS group was significantly reduced (P<0.05), the apoptotic rate was significantly increased (P<0.05), the protein levels of cyclin D1 and Ki67 were significantly reduced (P<0.05), and the protein level of cleaved caspase-3 was significantly increased (P<0.05). CONCLUSION Over-expression of FEZF1-AS1 promotes the viability and inhibits apoptosis of LPS induced vascular endothelial cells by inhibiting the expression of miR-363-3p.  相似文献   
6.
AIM: To detect the expression of miRNA-363 and SOX4 in osteosarcoma tissues and to investigate the effect of miRNA-363 on the viability and apoptosis of human osteosarcoma cell line MG-63.METHODS: Real-time PCR was used to detect the expression level and the relationship of miRNA-363 and SOX4 mRNA in the osteosarcoma tissues and the corresponding paratumorous tissues collected from 63 patients. The expression levels of miRNA-363 and SOX4 in osteosarcoma cell line MG-63 after transfected with miRNA-363 mimics were measured. The cell viability was measured by CCK-8 assay. Flow cytometry was used to monitor the changes of cell cycle and apoptosis. The changes of SOX4 and miRNA-363 expression levels in the MG-63 cells after transfection with SOX4 siRNA or pcDNA/SOX4 was detect by real-time PCR.RESULTS: The expressed level of miRNA-363 was lower, and the expression level of SOX4 was higher in the osteosarcoma tissues than those in the adjacent normal tissues. A significantly negative correlation between the expression levels of miRNA-363 and SOX4 was observed. The expression of miRNA-363 in the MG-63 cells after transfection with miRNA-363 mimics was significantly up-regulated, while the expression of SOX4 in the MG-63 cells was significantly down-regulated, with significant difference as compared with the cells transfected with miRNA-NC and control cells. The viability of MG-63 cells was inhibited, the cell cycle was arrested in G0/G1 phase, and the cell apoptosis was increased by transfection with miRNA-363 mimics. The relative protein expression levels of SOX4 in SOX4 siRNA group and pcNDA/SOX4 group were significantly different from those in negative control group, but the relative expression levels of miRNA-363 had no significant difference. Over-expression of SOX4 restored the viability of the MG-63 cells reduced by miR-363.CONCLUSION: The expression level of miRNA-363 is low in human osteosarcoma tissue. miRNA-363 may inhibits the viability of osteosarcoma cell line MG-63 and promotes cell apoptosis in vitro via inhibiting the SOX4 expression.  相似文献   
7.
Uneven ripening (UR) is a physiological disorder of unknown origin in ‘Bangalore blue’ grape (Vitis vinifera × Vitis labrusca) leading to wine of inferior quality. A preliminary study found wide variations in total dehydrogenase activity (TDH) of seeds from unevenly ripe berries. In our experiments, gibberellin (GA3) applied to young grapes increased seed TDH activity and reduced the incidence of uneven ripening to 2% compared with 35% in the control. In contrast, paclobutrazol (PBZ) decreased TDH activity and increased the incidence of the disorder to 58%. GA3-treated berries had higher concentrations of sucrose and TDH activity in seed representing mature seeds with high viability. In contrast, PBZ-treated and control berries had higher concentrations of glucose and lower TDH activity, indicating immature seeds with low viability. These results suggested that competition among developing berries can lead to differences in seed gibberellin content, seed viability and the rate of berry growth resulting in green, purple, and black berries at harvest. The study established the role of seed viability in uneven ripening and demonstrated that the incidence of the disorder is reduced by the application of GA3 to immature berries.  相似文献   
8.
蝴蝶兰花粉活力及柱头可授性研究   总被引:3,自引:1,他引:2  
喻兰  李杰 《中国农学通报》2017,33(11):54-58
蝴蝶兰花粉和柱头具有较高的活性,是确保其杂交成功的关键。为获得蝴蝶兰人工授粉的最佳时间参数,通过电镜扫描和TTC(氯化三苯基四氮唑)染色,对蝴蝶兰品种‘天香公主’的花粉活力进行研究,并用联苯胺-过氧化氢法测定其柱头可授性。结果表明,蝴蝶兰花粉块随着开放时间的延长,体积减小,颜色加深,质地变硬,活力减弱。TTC染色法检测表明,花粉活力率(染色率)大小为:开放1 天<花蕾期<花蕾展开期。柱头可授性测定显示,蝴蝶兰开花10~30 天内进行人工杂交能获得较高的成功率,其中10~15天授粉率最高。  相似文献   
9.
[目的]探究万寿竹种子脱水过程中,发芽及部分抗逆生理指标的变化情况,为万寿竹种子贮藏及采收提供理论依据.[方法]利用室温硅胶干燥法获得45.90%、40.50%、38.07%、33.08%、27.26%、16.67%、14.63%7个含水量梯度的种子,以未干燥的种子(49.12%)为空白对照,分别测定各个含水量梯度种子的生活力、发芽率、电导率、CAT、SOD、POD、AsA-POD活性、MDA、可溶性蛋白质含量.[结果]种子含水量保持在33.08%以上时,能保持较高的生活力、发芽率,当含水量下降到33.08%以下时,种子发芽率和生活力开始显著下降.[结论]万寿竹种子不耐脱水,属于顽拗性种子,贮藏时含水量应保持在33.08%以上.  相似文献   
10.
AIM:To investigate the effect of proline-spirooxindole on the viability and apoptosis of human non-small-cell lung cancer A549 cells. METHODS:The effect of proline-spirooxindole on the viability of A549 cells was determined by CCK-8 assay. The apoptosis was analyzed by flow cytometry. The effects of proline-spirooxindole on the expression of PARP and p53 and the phosphorylation of mTOR were determined by Western blot. RESULTS:After A549 cells were treated with proline-spirooxindole (25, 50 and 100 mg/L), the cell viability was decreased (P<0.01) compared with DMSO control group. The apoptotic rate was increased compared with DMSO control group (P<0.01). The protein expression of p53 was up-regulated, the increased apoptotic protein cleaved PARP was observed, and the phosphorylation of mTOR was inhibited (P<0.01). CONCLUSION:Proline-spirooxindole inhibits the viability of A549 cells and induces apoptosis, which may be related to the phosphorylation of mTOR.  相似文献   
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