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191.
为了对葡萄雄性不育基因进行定位研究,以可育葡萄‘魏可’(Vitis vinifera L.)为亲本构建的自交群体88株为试验材料,运用分离群体分组混合分析法(bulked segregant analysis,BSA),构建了可育株和不育株基因池,结合SSR技术对葡萄雄性不育基因进行定位研究和生物信息学分析。该研究筛选到2个与葡萄雄性不育基因连锁的SSR标记VVMD34和VVIB23,且位于该基因两侧,遗传距离分别为3.5cM和1.9cM。2个标记间物理距离为1 134kb,在该区域总共预测到了111个候选基因。该研究对葡萄雄性不育基因的精细定位及分子标记辅助育种奠定了良好的基础。  相似文献   
192.
Radiation-induced lung injury (RILI) is a potentially fatal and dose-limiting complication of thoracic radiotherapy. This study was to investigate the protective effects of grape seed pro-anthocyanidins (GSPs), an efficient antioxidant and anti-carcinogenic agent, on RILI. In our study, it was demonstrated that acute and late RILI was ameliorated after GSPs treatment possibly through suppressing TGF-β1/Smad3/Snail signalling pathway and modulating the levels of cytokines (interferon-γ, IL-4 and IL-13) derived from Th1/Th2 cells. In addition, a sustained high level of PGE2 was also maintained by GSPs treatment to limited fibroblast functions. As shown by electron spin resonance spectrometry, GSPs could scavenge hydroxyl radical (•OH) in a dose-dependent manner, which might account for the mitigation of lipid peroxidation and consequent apoptosis of lung cells. In vitro, GSPs radiosensitized lung cancer cell A549 while mitigating radiation injury on normal alveolar epithelial cell RLE-6TN. In conclusion, the results showed that GSPs protects mice from RILI through scavenging free radicals and modulating RILI-associated cytokines, suggesting GSPs as a novel protective agent in RILI.  相似文献   
193.
王文娟  贺达汉 《昆虫知识》2006,43(6):851-853
二斑叶螨Tetranychus urticae Koch近几年在葡萄园内暴发为害,通过室内饲养,组建其取食葡萄叶片时的实验种群生命表,结果表明在室温(21~28℃)下,该虫的内禀增长率(rm)、周限增长率(λ)、净增殖率(R0)、种群世代平均周期(T)和种群加倍时间(t)分别为0.2066,1.2295,39.5929,17.8d和3.35d。  相似文献   
194.
Tomato (Lycopersicon esculentum) is a vegetable rich in antioxidants, such as lycopene, lutein, and zeaxanthin. Their presence is responsible for the characteristic ability of this product to inhibit the formation of reactive oxygen species, including singlet oxygen. The grapes and wines derived from grapes also contain powerful antioxidants. The antioxidant effect is derived from the polyphenols such as resveratrol and proanthocyanidin. Resveratrol is phytoalexin that is synthesized via the activation of the gene, stilbene synthase (STS). We decided to determine if the introduction of this gene into Lycopersicon esculentum Mill could modify its antioxidant activity. Using Electronic Paramagnetic Resonance (EPR) spectroscopy, which permits the detection of antiradical activity, especially OH (hydroxyl radical), we showed that the antioxidant activity of the products, into which the gene STS had been introduced, was almost double than that of natural products and that their activity was especially pronounced due to ripening. Moreover, resveratrol concentrations in modified tomatoes were much higher than that found in the individual fruit. In the isolated hearts subjected to ischemia/reperfusion, the rats fed with modified tomato exhibited better cardiac performance, reduced myocardial infarct size and decreased number of apoptotic cardiomyocytes, and reduced oxidative stress compared to unmodified tomato or resveratrol alone indicating superior cardioprotective abilities of modified tomatoes.  相似文献   
195.
为提高干旱绿洲区农田地表过程的科学认识及改善农业水管理,该研究基于涡度相关技术,运用葡萄园生长季能量平衡观测资料,分析了不同时间尺度的水热通量变化特征,以及干旱平流和冠层导度(Gc)在不同生长阶段上对水热通量的影响,并应用通径分析研究了环境因子对潜热通量(LE)的影响路径和程度。结果表明:(1)日尺度上,LE呈现出不同程度多峰状,其余水热通量总体上呈单峰状。整体上,各生长阶段日间净辐射(Rn)>LE>感热通量(H)>土壤热通量(G)。G相较于Rn呈现出明显的滞后现象。(2)整个生长季上,LE和H分别占白天可利用能量(Rn-G)的86%和14%,表明LE始终是白天葡萄园可利用能量的主要消耗项。干旱平流对白天LE的贡献范围为5%~59%,全生长季平均贡献为28%;Gc对LE的影响在生长季上呈动态变化,且在新梢生长期和落叶期对LE的影响强于中间生长阶段。(3)LE主要受Rn的影响,饱和水汽压差(VPD)和气温(Ta)对LE...  相似文献   
196.
Abstract. Mark–release–recapture is used to quantify displacement by adults of the North American grape berry moth, Endopiza viteana Clemens (Lepidoptera: Tortricidae) under field conditions. Moths marked with fluorescent dust are released eight times in the centre of a vineyard over 2 years, and recaptured using pheromone traps and interception traps. In vineyards, male moths are recaptured an average of 13.8 ± 0.8 m from the release site (maximum 58.2 m), whereas female displacement is similar with average flight distances of 11.4 ± 6.7 m (maximum 41.2 m). Increasing wind speed during moth flight activity periods suppresses displacement by both sexes, and females are less likely than males to fly in winds above 0.6 m s?1. The majority of males are recaptured upwind from the release site or at a tangent to the overall mean wind direction when responding to pheromone traps, whereas female moths trapped in interception traps exhibit a large variability in direction from the release point. Releases of marked moths in woods adjacent to a vineyard demonstrates interhabitat movement by E. viteana males and by a single female. The average maximum displacement by males during interhabitat movement is 105.4 ± 3.9 m, significantly greater than the average maximum of 39.7 ± 6.7 m inside the vineyard habitat.  相似文献   
197.
Ice wine is a sweet dessert wine made from pressing grapes naturally frozen on the vines. The structure and metabolic characteristics of native microbial community dominated by organics and nutrients transformation in fermenting process of ice wine on the grape skin are likely to change due to climate events. Our objective was to evaluate the influence of harvest time on structure and metabolic characteristics of bacterial and fungal communities on Vidal ice grape surface. Vidal grape samples were picked between October and December in 2018; Harvest 1 (VG1): 14 October; Harvest 2 (VG2): 16 November; Harvest 3 (VG3): 18 December. Vishniacozyma, Alternaria, Cladosporium, Stenotrophomonas, unidentified_Cyanobacteria and Sphingomonas existed in all harvest dates and were the main genera widespread in most grape samples from the three harvest periods. Saprotrophic fungi and bacteria involved in metabolism were also dominant. For fungi, wood saprotrophs and unidentified saprotrophs were detected comprising Phoma, Didymella, Filobasidium and Clavaria. Delayed harvest of ice grapes has a distinct advantage for pathogen reduction compared with that of normally harvested grapes. Among bacteria, the most frequently occurring types in the metabolism category were energy metabolism, carbohydrate metabolism and lipid metabolism. In short, the harvest period can positively regulate the function of Vidal ice grape epidermal microorganisms.  相似文献   
198.
We aimed to clarify whether grape seed polyphenols (GSPs) are candidates therapeutic agents against diabetes mellitus, and to determine what degree of GSP oligomerization has the most potent efficacy. We studied the protective effects of various molecular weight GSPs (monomer, oligomer, polymer, and oligonol) on high glucose-induced cytotoxicity. In the present study, a high concentration of glucose (30 mM) induced cytotoxicity and oxidative stress (reactive oxygen species and nitric oxide) in cultured LLC-PK1 cells, but treatment with GSPs, especially oligomer GSPs, had potent protective effects against high glucose-induced oxidative stress. In addition, high glucose induced nuclear translocation of nuclear factor-kappa B, and increased expression of cyclooxygenase-2, inducible nitric oxide synthase, and bax, but GSP treatment inhibited them. These results indicate that GSPs have protective effects against high glucose-induced cytotoxicity, and among them, oligomer GSPs have more potent effects than other GSPs (monomer, polymer, and oligonol) on high glucose-induced renal cell damage.  相似文献   
199.
Methoxypyrazines are a family of potent volatile compounds of diverse biological significance. They are used by insects and plants in chemical defence, are present in many vegetables and fruit and, in particular, impart herbaceous/green/vegetal sensory attributes to wines of certain varieties, including Cabernet Sauvignon. While pathways for methoxypyrazine biosynthesis have been postulated, none of the steps have been confirmed genetically. We have used the F2 progeny of a cross between a rapid flowering grapevine dwarf mutant, which does not produce 3‐isobutyl‐2‐methoxypyrazine (IBMP), and Cabernet Sauvignon to identify the major locus responsible for accumulation of IBMP in unripe grape berries. Two candidate methyltransferase genes within the locus were identified and one was significantly associated with berry IBMP levels using association mapping. The enzyme encoded by this gene (VvOMT3) has high affinity for hydroxypyrazine precursors of methoxypyrazines. The gene is not expressed in the fruit of Pinot varieties, which lack IBMP, but is expressed in Cabernet Sauvignon at the time of accumulation of IBMP in the fruit. The results suggest that VvOMT3 is responsible for the final step in methoxypyrazine synthesis in grape berries and is the major determinant of IBMP production.  相似文献   
200.
以‘无核白’葡萄为对照,以其自然营养变异系‘长穗无核白’、‘长粒无核白’、‘大粒无核白’、‘W3’与‘W7’为材料,在新疆吐鲁番鄯善田间栽培条件下比较其果实及光合作用特性,为‘无核白’系列葡萄优良品种选育提供依据。结果表明:(1)供试各营养系具有较高的光、热利用能力,叶片日平均净光合速率(5.527 7~7.412 3μmol.m-2.s-1)均大于对照(4.879 7μmol.m-2.s-1);除‘长穗无核白’外,其余营养系均无明显光合‘午休’现象。(2)供试条件下净光合速率与田间空气温度、叶片温度、叶片表面蒸汽压差呈正相关;而气孔导度、光照强度等因子是‘无核白’系列葡萄光合作用的非决定因素。(3)‘长穗无核白’的穗长(36.43 cm)是对照(25.27 cm)的1.44倍;各营养系果粒均大于对照,其中‘W3’、‘大粒无核白’、‘长穗无核白’、‘长粒无核白’果粒(2.096 0、2.202 7、2.019 3、1.470 3 g)极显著大于对照(1.057 7 g)。(4)‘长粒无核白’果粒耐压力和果梗耐拉力均极显著优于对照,其他营养系与对照无显著差异;果粒较大的‘W3’、‘大粒无核白’、‘长粒无核白’等可溶性固形物含量(22.92%、23.57%、23.17%)与对照(23.85%)无差异。综合分析认为,供试营养系‘W3’、‘W7’和‘长粒无核白’相对较优良,宜进一步研究;研究证明果实与叶片光合作用特性指标可用于葡萄营养系选种。  相似文献   
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