Estimating the germination dynamics of Plasmopara viticola oospores using hydro-thermal time

The effects of environmental conditions on the variability in germination dynamics of Plasmopara viticola oospores were studied from 1999 to 2003. The germination course was determined indirectly as the relative infection incidence (RII) occurring on grape leaf discs kept in contact with oospores sampled from a vineyard between March and July. The time elapsed between 1 January and the infection occurrence was expressed as physiological time, using four methods: (i) sums of daily temperatures > 8°C; (ii) hourly temperatures > 10°C; (iii) sums of hourly rates from a temperature-dependent function; or (iv) sums of these rates in hours with a rain or vapour pressure deficit ≤ 4·5 hPa (hydro-thermal time, HT). An equation of Gompertz in the form RII = exp[− a  · exp(− b  · HT)] produced an accurate fit for both separate years ( R ² = 0·97 to 0·99) and pooled data ( R ² = 0·89), as well as a good accuracy in cross-estimating new data ( r between observed and cross-estimated data were between 0·93 and 0·99, P  < 0·0001). It also accounted for a great part of the variability in oospore germination between years and both between and within sampling periods. Therefore, the equation of Gompertz (with a  = 15·9 ± 2·63 and b  = 0·653 ± 0·034) calculated over hydro-thermal time, a physiological time accounting for the effects of both temperature and moisture, produced a consistent modelling of the general relationships between the germination dynamics of a population of P. viticola oospores and weather conditions. It represents the relative density of the seasonal oospores that should have produced sporangia when they have experienced favourable conditions for germination.     

A host-pathogen simulation model: powdery mildew of grapevine

An epidemiological model simulating the growth of a single grapevine stock coupled to the dispersal and disease dynamics of the airborne conidia of the powdery mildew pathogen Erysiphe necator was developed. The model input variables were either climatic (temperature, wind speed and direction) or related to the pathogen (location and onset of primary infection). The environmental input variables dictated plant growth and pathogen spread (latent period, infection, lesion growth, conidial spore production and release). Input parameters characterized the crop production system, the growth conditions and the epidemiological characteristics of the pathogen. Output described, at each time step, number, age and pattern of healthy and infected organs, infected and infectious leaf area and aerial density of spores released. Validation of the model was achieved by comparing model output with experimental data for epidemics initiated at different times of host growth. Epidemic behaviour for two contrasting years of crop development and 7 phenological stages at the time of primary infection (PI) was examined. For PI occurring at day 115 a vine with late budbreak (1998) showed 58% of primary leaves diseased at flowering compared with only 19% for a vine with early budbreak (2003). Depending on the phenological stage at PI (1–4 leaves), the proportion of diseased primary leaves decreased from 42% to 6% at flowering. Simulations suggested that differences resulted from the interplay between the timing of the first sporulation event, the phenological stage at the time of initial infection, and the age structure and spatial distribution of the leaf population.     

华东葡萄抗白粉病基因差异表达cDNA克隆与序列分析

为筛选和克隆华东葡萄抗白粉病相关基因,以高抗葡萄白粉病的华东葡萄株系白河-35-1为材料,采用mRNA差异显示(DDRT-PCR)技术进行在白粉病病原菌诱导下抗白粉病差异表达基因的研究,筛选出适宜DDRT-PCR的引物组合184对,获得抗白粉病差异表达的cDNA片段13个,序列分析结果显示其功能分别涉及转录调控、能量代谢、蛋白合成、防御反应等生理生化过程,表明华东葡萄白河-35-1抗白粉病是诸多代谢途径相互协调作用的结果。这些差异片段的获得为探明葡萄抗白粉病分子机制提供了前期理论基础。     

Powdery mildew development is positively influenced by grapevine vegetative growth induced by different soil management strategies

In various crop species, high levels of powdery mildew infection and severity have been associated with high vegetative vigour. In grapevine this relationship has also been observed by vine growers, though it has not been quantified. This study was undertaken to investigate the relationship between the development of powdery mildew on leaves and berries and canopy growth, and thus to quantify the relationship between the pathogen and its host. Over a two-year period (2005 and 2006), an experiment was carried out in a vineyard (cv. Aranel) near Montpellier, southern France. Several levels of canopy growth were generated by implementing four soil management strategies: i) perennial cover crop in the inter-row, ii) annual cover crop in the inter-row, iii) chemical weed control over the entire soil surface, iv) chemical weed control all over the soil surface and drip irrigation and fertilization in the row. Powdery mildew was artificially inoculated on experimental sub-plots with Erysiphe necator [Schw.] Burr. conidia. The most vigorous vines developed a larger number of diseased leaves and a higher percentage of mildewed berries compared to low-vigour vines. The major explanatory variable highlighted in these experiments was the shoot leaf number, mainly early in the season. A higher leaf population generated a larger number of powdery mildew colonies close to grapes and consequently a higher probability of berry infection. Our experimental results provide evidence of a positive relationship between powdery mildew development and grapevine vegetative development. These results provide an opportunity to develop new IPM strategies in vineyards.     

广西罗城毛葡萄多酚、黄酮和白藜芦醇的组成特性及其抗氧化活性研究

【目的】评价毛葡萄的营养与功能活性,为其综合开发利用提供理论参考。【方法】以2014年采自广西罗城的13个株系的毛葡萄为材料,采用有机溶剂浸提法从毛葡萄中提取多酚、黄酮和白藜芦醇等抗氧化活性物质,用比色法测定总多酚与总黄酮含量,用高效液相色谱法测定白藜芦醇含量,用DPPH、ABTS和还原力等方法分析其抗氧化活性。【结果】所选样品的多酚、黄酮、白藜芦醇含量及抗氧化活性在不同株系间存在较大差异,其中多酚含量为1.97~3.14mg/g,黄酮含量为0.41~1.35mg/g,白藜芦醇含量为0.75~8.81μg/g,抗氧化活性的DPPH自由基清除率为35.07%~89.34%,ABTS自由基清除率为17.86%~32.32%,还原力为1.21~2.32mg/g。【结论】广西毛葡萄含有丰富的多酚和黄酮类物质,抗氧化活性较高,具有很好的应用潜力。     

葡萄miR169及其靶基因的生物信息学分析

[目的]明确葡萄miR169(vvi-miR169)基因家族在葡萄生长发育及逆境胁迫响应中的重要作用,为其在葡萄分子育种和抗逆新品种选育中的应用提供参考依据.[方法]利用miRNA、Phytozome、NCBI等数据库及ClustalX 2.1、MEGA 6.0、RNAfold WebServer、psRNATarget等在线软件对vvi-miR169基因家族的序列分布、定位特征、二级结构、发育进化树和靶基因调控功能进行生物信息学分析.[结果]在miRBase中搜索到25条vvi-miR169基因同源序列,分别分布在6条染色体上,其中以位于Chr11上的序列最多,共有17条,位于Chr01、Chr04和Chr14上各有2条,而在Chr08和Chr17上各有1条.vvi-miR169基因家族成熟序列的碱基保守性很高,其前体序列均可形成稳定的二级茎环结构,且位于同一条染色体上的miR169基因序列显示出相对更近的亲缘关系.vvi-miR169基因家族共预测到21个靶基因,绝大部分miRNA都有多个靶基因,且不同miRNA具有相同的靶基因,其中有22个miRNA靶基因均含有GSVIVT01015120001(NF-YA转录因子).[结论]vvi-miR169基因家族序列保守性较高,家族特征明显,且具有相似的调控功能;NF-YA转录因子是vvi-miR169基因家族最主要的靶基因,也是葡萄生长发育过程中抗逆境胁迫的主要调控元件.     

肉桂酸和不同光质对葡萄愈伤组织增殖及白藜芦醇累积的效应

以葡萄品种"黑比诺"叶片诱导出的愈伤组织为材料,研究了不同浓度的肉桂酸和不同光质对葡萄愈伤组织增殖及对其中白藜芦醇合成的影响.结果表明:肉桂酸浓度为21mg·mL-1时,白光有最利于葡萄愈伤组织的增殖;在肉桂酸浓度为27mg·mL-1时,绿光最有利于葡萄愈伤组织的增殖;白藜芦醇含量在肉桂酸浓度为27mg·mL-1的白光下最高,但产量却在蓝光下最高;葡萄愈伤组织采收后经紫外强度8μmol.m-2.s-1处理10min可显著提高其中的白藜芦醇含量;而当肉桂酸与紫外两个因素共同作用时对白藜芦醇合成的促进作用不如两因素单独作用时的强.     

贵州葡萄属3个野生种浆果品质分析

从外观品质和内在品质两个方面评价了原产于贵州的6份野生葡萄浆果品质。结果表明,贵州野生葡萄果粒小、糖酸比低、出汁率低、丹宁含量高。果实品质存在种间差异,其中刺葡萄的果穗和果粒较大,毛葡萄的可溶性固形物含量(15.97%)高于对照水晶,而腺枝葡萄的单宁含量高达1 178.17 mg.L-1,为对照的2.63倍。同种不同单株间果实品质差异大小因种而异,外观品质中差异最明显的是腺枝葡萄的两个单株,刺葡萄的两个单株品质差异也较明显,而毛葡萄的两个单株品质差异较小。刺葡萄菜园刺2006年和2007年的果实品质明显不同。     

不同药剂对打破玫瑰香葡萄芽休眠的效果研究

以日光温室内葡萄品种‘玫瑰香’（Vitis vinifera ‘Muscat Hamburg’）为试材,选择不同化学药剂对其进行破眠试验,探讨单氰胺等外源生长调节剂打破休眠的效应以及休眠过程中抗性物质含量的变化。结果表明：2.5% 单氰胺打破葡萄的休眠效果最好,可使萌芽期提前15天左右,萌芽整齐度及萌芽速率高,显著提高了SOD、POD酶的活性,对CAT酶活性有一定的抑制作用,对丙二醛含量的影响不显著;200 mg/LGA3对打破休眠基本无效甚至有抑制作用,处理后萌芽率低于对照,但可促进芽体形成新梢;150 mg/L 6-BA对打破休眠亦有一定的效果,但对终萌芽率影响甚微。     

山葡萄霜霉病发生规律及其抗病性的进一步探讨

霜霉病是山葡萄的主要病害。通过对葡萄园气象条件与霜霉病的多年观测,我们对山葡萄霜霉病的发病规律有了进一步的认识,发现在一定的气候条件下病害的潜育期不超过24小时,比前人揭示的病害潜育期明显缩短。同时,发现在某一品种寄主下的病原菌,在品种间的传播能力有显著差别。为此在防御措施上提出了新的见解。