葡萄CBF4基因生物信息学及其对低温和硅酸钾响应分析

为探究葡萄CBF4基因的结构和表达特征,该研究以葡萄为材料,对葡萄 CBF4基因进行生物信息学及低温和硅酸钾响应分析。结果表明:(1)CBF4蛋白定位在细胞核,有5个磷酸化位点和14个糖基化位点,无信号肽,是一个亲水的、脂溶性较差的膜外蛋白。二级结构以无规则卷曲为主,比例为56.88%。该蛋白包含一个AP2/EREBP结构域。(2)CBF4蛋白的多序列和系统进化分析表明酿酒葡萄与美洲葡萄的同源性最高、亲缘关系最近。(3)荧光定量 PCR 分析显示,低温胁迫后CBF4基因在葡萄叶片中表达水平上调,说明CBF4基因可能参与了葡萄叶片低温胁迫的响应。低温条件下,施加硅酸钾CBF4基因表达具有差异性,说明该基因在不同的葡萄组织中对硅酸钾的响应机制可能不同。以上结果为进一步研究葡萄CBF4基因的功能和机理奠定了基础。     

Hybridization of cultivated Vitis vinifera with wild V. californica and V. girdiana in California

Hybridization of introduced domesticates and closely related natives is well documented in annual crops. The widespread introduction of the domesticated grapevine, Vitis vinifera, into California where it overlaps with two native congenerics, with which it is interfertile, provides opportunity to investigate hybridization between woody perennials. Although geographically widespread, the introduction over the past two centuries has been limited to a few elite clonal cultivars, providing a unique opportunity to study the effects of hybridization on the native species. The amount of hybridization with V. vinifera and the genetic diversity of wild‐growing Vitis californica and Vitis girdiana were examined using nineteen microsatellite markers. STRUCTURE analysis was used to define hybrid and introgressed individuals and to analyze genetic structure of the native species. FAMOZ software was used to identify which V. vinifera cultivars served as parents of F₁ hybrids. The three species were clearly distinguished by STRUCTURE analysis. Thirty percent of 119 V. californica vines were hybrids. The domesticated parent was identified for 16 F₁ hybrid vines; the original California cultivar, ‘Mission’, was the parent of eight. Backcrosses were also found, showing introgression into subsequent generations. Similar results were obtained for a small sample of V. girdiana. Removing hybrids greatly reduced the genetic variation of the presumed pure species, among which there was essentially no genetic structure. Limited genetic variability indicates the California natives may be threatened by genetic erosion. The discovery of F₁ hybrids of ‘Mission’, a cultivar not grown in the areas for ~100 years, suggests long generation times for wild vines that, often, grow into expansive liana and propagate by layering, all factors that limit recruitment in populations already disjunct by habitat lose. Hermaphroditic flowers and fruit that is more attractive to birds may favor the production of backcross seed and establishment of introgressed individuals.     

美国酿酒葡萄品种在北京地区的生长和适应性表现

调查研究了首次引进的13个美国酿酒葡萄品种在北京地区栽培后的植物学性状、果实品质和抗寒及抗霜霉病能力,并与传统的欧亚种酿酒葡萄及砧木品种进行了比较与分析,总结了它们之间的植物学性状与抗逆性的差异。本试验选出了在抗寒及抗霜霉病方面表现优良的美国酿酒葡萄品种,为这些品种在我国的实际栽培推广提供科学依据。     

Influence of Williopsis saturnus yeasts in combination with Saccharomyces cerevisiae on wine fermentation

Aim: To examine the growth and survival of Williopsis saturnus strains along with wine yeast Saccharomyces cerevisiae in grape must. Methods and Results: For this study, fermentations were performed in sterilized grape must at 18°C. Inoculum level was 5 × 10⁶ cells per ml for each yeast. The results showed that W. saturnus yeasts exhibited slight growth and survival depending on the strain, but they died off by day 5. Saccharomyces cerevisiae, however, dominated the fermentation, reaching the population of about 8 log CFU ml^?1. It was observed that ethanol formation was not affected. The concentrations of acetic acid, ethyl acetate and isoamyl acetate were found higher in mixed culture experiments compared to control fermentation. The results also revealed that higher alcohols production was unaffected in general. Conclusion: Fermentations did not form undesirable concentrations of flavour compounds, but production of higher levels of acetic acid in mixed culture fermentations may unfavour the usage of W. saturnus in wine making. Significance and Impact of the Study: This study provides information on the behaviour of W. saturnus together with S. cerevisiae during the alcoholic fermentation.     

河西干旱区酿酒葡萄生长的气象条件

按照平行观测的原则，利用2002、2003年两年田间试验资料，采用数理统计方法分析了河西内陆干旱区目前国内广泛种植的8个不同熟性酿酒品种的生长发育规律及其气象影响因子。结果表明：（1）新梢、果实生长呈抛物线型，生长关键期分别出现在5月上旬～6月中旬、7月上旬～8月上旬；糖分累积呈“S”型，积累关键期出现在8月中旬～9月上旬。枝条、果实、含糖量增长峰值点位相出现时间按中早熟、中晚熟、晚熟品种依次推后。（2）中早熟品种需≥10℃积温2800～2900℃，中晚熟种2900～3100℃，晚熟种3000～3200℃；新梢生长期35～50d，需≥10℃积温620～750℃。花期7～15d，需≥10℃积温130～320℃。浆果生长期50～65d，需≥10℃积温1100～1400℃。浆果成熟期35～50d，需≥10℃积温640～940％。（3）新梢生长量与日平均气温、日照时间和土壤湿度呈正相关。气温低于11～12℃时，新梢停止生长；果粒增长速度与平均气温、最高气温呈负相关，与相对湿度、降水量呈正相关。果粒增长适宜气温为20～21℃，超过21℃，增速明显变缓；含糖量积累与光、热因子均呈正相关，与水分因子呈负相关。品种熟性越晚，对气象条件反映越敏感。气温低于7～7．9℃时，糖分停止积累。通过酿酒葡萄适生气候条件分析，为区域化布局、产业化发展提供理论依据。     

外源激素和病原侵染对采后葡萄呼吸速率及组织内源激素的影响

葡萄采后施用外源ABA可显著刺激其呼吸速率和乙烯释放率,ABA对呼吸的促进作用大于C2H4;当葡萄被交链孢和灰霉葡萄抱侵染后,呼吸和乙烯释放均加强。交链孢侵染的葡萄呼吸速率在孢子形成后2d达最大值,而灰霉葡萄孢侵染的葡萄呼吸速率在孢子形成时即达最大值。葡萄感病后,落粒现象加重,组织内源ABA和C2H4含量增加,IAA和GA3含量减少。     

Quest for wine yeasts—An old story revisited

Numerous studies have described the yeast biota of grapes, and grape must in order to understand better the succession of yeasts during fermentation of wine. The origin of the wine yeasts has been rather controversial. By using more elaborate isolation methods, classical genetic analysis and electrophoretic karyotyping of monosporic clones, with this study, credible proof now exists that the vineyard is the primary source for the wine yeasts and that strains found on the grapes can be followed through the fermentation process.     

Conversion of tartrate to malate and monoethyl tartrate in grape leaves

¹⁴CO₂ evolution from l(+)-tartrate-[U-¹⁴C] in grape leaves was observed confirming the dissimilation of tartrate. 30 sec after the administration of l(+)-tartrate-[U-¹⁴C], 3 compounds were found to contain ¹⁴C. Two of them were identified as monethyl tartrate and malate by chromatographic and MS studies. It is suggested that the ¹⁴CO₂ evolved is derived from malate-[U-¹⁴C] which is metabolically formed from l(+)-tartrate-[U-¹⁴C], and that monoethyl tartrate is not an intermediate for the conversion to malate.     

Starch synthetases from Vitis vinifera and zea mays

ADPglucose: α-1,4-glucan α-4-glucosyltransferases (starch synthetases) from leaves of Vitis vinifera and leaves and kernels of Zea mays were chromatographed on DEAE-cellulose columns. One form of the enzyme was present in grape leaves having activity both in the presence and absence of primer. Two forms were present in both leaves and kernels of maize. The second peak of activity in maize leaves and the first peak in maize kernels synthesized a polyglucan in the absence of primer. A peak of branching enzyme (Q-enzyme) occurred between the two starch synthetase peaks with both tissues. When fractions containing starch synthetase and branching enzyme were added to the first leaf starch synthetase peak, up to 100-fold activation of the unprimed reaction occurred. Branching enzyme did not stimulate the unprimed activity of the first kernel peak and no branching enzyme could be detected in this peak. The unprimed product was a branched polyglucan with mainly α-1,4-links.