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411.
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.  相似文献   
412.
葡萄胚胎发育与败育过程中胚珠的多胺含量变化   总被引:2,自引:0,他引:2  
花后40~60d期间,种子败育型无核葡萄胚珠的3种多胺含量明显低于有核葡萄,据此认为无核葡萄胚珠中多胺含量急剧下降和较低的多胺水平可能是导致葡萄胚胎败育的重要原因。(Spd Spm)/Put和Spm/PAs比值变化与葡萄胚胎发育密切相关,较低的比值不利于胚胎的正常分化。  相似文献   
413.
宁夏贺兰山东麓葡萄产业生态系统服务功能价值评估   总被引:1,自引:0,他引:1  
利用宁夏回族自治区统计局、宁夏回族自治区葡萄产业发展局和国家统计局等的相关统计数据,从食品生产、固碳释氧、净化大气、土壤保持、涵养水源、节水增效、生态旅游和生态扶贫等角度,对宁夏贺兰山东麓葡萄产业生态系统服务价值进行评估.结果表明: 1)宁夏贺兰山东麓葡萄产业生态系统服务功能价值为35.98亿元,其中直接效益为22亿元,生态效益为13.98亿元.生态效益占整个产业生态系统服务价值的38.85%.2)生态效益中,各项功能的价值量依次为: 生态扶贫>生态旅游>固碳释氧>节水增效>净化大气>土壤保持>涵养水源.3)生态效益中,生态扶贫的价值最高,占64.39%;生态旅游的价值次之,占24.47%.对葡萄产业进行生态系统服务功能价值评估,既可以让人们在看到葡萄产业直接效益的同时,又可以意识到葡萄产业所带来的生态效益.这对全面指导葡萄产业健康持续发展具有重要参考价值.  相似文献   
414.
  • The prevention of Botrytis cinerea infection and the study of grape seedlessness are very important for grape industries. Finding correlated regulatory genes is an important approach towards understanding their molecular mechanisms.
  • Ethylene responsive factor (ERF) gene family play critical roles in defence networks and the growth of plants. To date, no large‐scale study of the ERF proteins associated with pathogen defence and ovule development has been performed in grape (Vitis vinifera L.). In the present study, we identified 113 ERF genes (VvERF) and named them based on their chromosome locations. The ERF genes could be divided into 11 groups based on a multiple sequence alignment and a phylogenetic comparison with homologues from Arabidopsis thaliana. Synteny analysis and Ka/Ks ratio calculation suggested that segmental and tandem duplications contributed to the expansion of the ERF gene family. The evolutionary relationships between the VvERF genes were investigated by exon–intron structure characterisation, and an analysis of the cis‐acting regulatory elements in their promoters suggested potential regulation after stress or hormone treatments.
  • Expression profiling after infection with the fungus, B. cinerea, indicated that ERF genes function in responses to pathogen attack. In addition, the expression levels of most ERF genes were much higher during ovule development in seedless grapes, suggesting a role in ovule abortion related to seedlessness.
  • Taken together, these results indicate that VvERF proteins are involved in responses to Botrytis cinerea infection and in grape ovule development. This information may help guide strategies to improve grape production.
  相似文献   
415.
DELLA蛋白是GA信号传导途径的核心作用元件,属于GRAS核转录调节因子家族。该研究以‘魏可’葡萄品种为试材,通过基因克隆、启动子分析、染色体定位、基因蛋白结构及系统进化分析,鉴定VvRGL1和VvRGL2精确序列,预测其潜在功能,并采用qRT-PCR技术检测VvRGL基因应答GA在果皮、果肉及种子(区)的时空表达特征。结果表明:(1)VvRGL1及VvRGL2的染色体定位为Chr14和Chr7,开放阅读框(ORF)为2 007bp和1 815bp,编码氨基酸数量为668和604个;二者均含有GRAS保守结构域,但却不具备DELLA结构域,属于GRAS转录因子大家族成员,而不属于DELLA亚家族;基因结构分析表明,VvRGL1的DNA序列有1个内含子,2个外显子,而VvRGL2的DNA序列无内含子,有1个外显子,基因结构高度保守;进化分析表明,VvRGL1与拟南芥和柑桔的亲缘关系较近,而VvRGL2与草莓和杨树的亲缘关系较近。(2)2个基因的启动子均含有响应赤霉素和胚乳发育相关的作用元件,表明它们可能参与响应GA信号传导和种子胚乳发育过程。(3)qRT-PCR结果显示,外源GA处理均不同程度降低了2个基因在葡萄果皮和种子区的表达,但却上调了其在幼果期果肉中的表达,表明在果皮与种子(区)中,GA可能通过抑制葡萄VvRGL1/RGL2基因的表达参与调控葡萄无核果实的发育。本研究结果为进一步阐明VvRGL在赤霉素信号传导及葡萄无核果实发育机理中的作用机制提供重要依据。  相似文献   
416.
Ochratoxin A (OTA) is a very dangerous mycotoxin, the presence of which is often reported in different foods, as well as in beverages such as grapes, grape juices and wines. Detoxifying these products is therefore of prime importance in protecting consumer health, and biological approaches have been the most promising methods. In this report, 40 isolates representing the black apergilli species Aspergillus carbonarius, A. niger aggregate and A. japonicus, isolated on French grapes, were assessed for OTA degradation capacities in CZAPEK yeast extract broth (CYB) and in a synthetic grape juice medium (SGM) contaminated with OTA at 2 mg L(-1) (5 microM). It was clearly observed that in both media these fungi had the ability to degrade OTA to OTalpha (ochratoxinalpha). However, there were differences between the media used and species tested during OTA degradation. In SGM and CYB, 77% and 45% of the isolates, respectively were able to degrade more than 80% of the OTA. Despite a better growth on SGM, specific OTA degradation was higher on CYB for most of the isolates. Kinetic studies carried out on SGM with three black Aspergillus isolates all showed different OTA degradation rates. After 9 days of incubation, OTalpha had decreased, whereas an unknown compound appeared. A. niger could be the first interesting species for OTA detoxification processes, followed by A. japonicus.  相似文献   
417.
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。  相似文献   
418.
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.  相似文献   
419.
Abstract

The present work was conducted to evaluate the efficacy of Trichogramma evanescens (Westwood) in controlling the grape berry moth Lobesia botrana (Schiff) in two grape farms, in El-Beheira and El-Gharbia Governorates, northern Egypt during 2004 and 2005 seasons. T. evanescens was mass produced on Sitotroga cerealella (Olivier) eggs in the National Research Centre in Egypt. The horizontal and vertical searching activity of T. evanescens was studied to determine the proper way of distributing the Trichogramma cards in vineyards. Field experiments were also conducted to evaluate T. evanescens efficacy to control L. botrana on a large scale. Parasitism by T. evanescens on L. botrana eggs was greatly affected with the horizontal or vertical distance from the release points as well as with the rate of release. Parasitism reached over 97% and the percentage of reduction in damage caused by the pest reached 96.8% in treated plots. A significant increase in the crop was achieved in treated plots. T. evanescens could be a potential candidate for biological control of the grape moth in vineyards.  相似文献   
420.
日灼对酿酒葡萄‘霞多丽’果实品质与解剖结构的影响   总被引:1,自引:0,他引:1  
以酿酒葡萄品种‘霞多丽’为试验材料,采用石蜡切片与CFDA荧光染色观察日灼果皮细胞结构与细胞活性变化,同时测定日灼发生后葡萄果实品质及相关生理指标变化,以揭示日灼对果实品质与细胞结构的影响。结果表明:(1)随着葡萄日灼病加重,果实表皮颜色由浅黄色逐渐加深,后期甚至出现细胞坏死。(2)果实发生日灼后,果实硬度与含水量下降,细胞壁含量增加,果皮从外向内第1~3层细胞明显变小,细胞壁增厚。(3)随着日灼病加重,果皮细胞破裂,且破裂数量增加,细胞活性也随之下降,果皮保护功能逐渐丧失,果肉细胞逐渐失水导致了果实皱缩;重度日灼果实周缘维管束木质部导管受到果皮细胞失水断裂的影响,出现断裂变形。(4)在葡萄果实日灼发生过程中,受到高温与强光照胁迫影响,同时伴随着水分散失增加,果实可溶性固形物含量和总糖含量增加,但有机酸含量降低,糖酸比随之增加;以上各品质指标值的大小与果实水分含量密切相关。研究发现,日灼引起了葡萄果实结构变化与生理代谢的紊乱,随着日灼程度加重,果皮细胞逐渐死亡,果实内水分大量散失,果实糖含量增加,严重影响了葡萄果实的外观和内在品质。  相似文献   
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