大豆霜霉病抗病机制和防治研究

大豆霜霉病是影响大豆生产和品质的主要真菌类病害之一,广泛分布于我国的各个大豆产区,尤其以潮湿多雨地区更为严重,极大影响了大豆的品质和产量。目前,大豆抗霜霉病机制领域研究较为滞后。本文从大豆霜霉病的侵染及发病规律、植物及大豆抗霜霉病主要机理、抗病基因研究进展和防治措施,总结大豆抗霜霉菌病研究面临的问题并展望研究方向,以期为后续大豆霜霉病抗病分子机理研究、高抗霜霉病大豆种质资源开发等提供理论借鉴。     

葡萄霜霉病的综合防治

葡萄霜霉病是葡萄生长季后期的常见病，其危害很大，现已成为葡萄生产中最主要的病害之三葡萄霜霉病的症状葡萄霜霉病主要危害叶片，也能侵染新稍、果柄、花梗、果实等．叶片发病，初期呈现半透明油质状小斑点，后扩展为黄褐色大班．潮湿时病斑背面产生白色霜状霉层，即为病菌的抱囊梗和抱子囊．病班最后变揭干枯，叶片早落．其他部位发病症状也同叶片相近，病部激凹陷．幼果染病后，油部褪色，变硬下陷，并生白色霜状零层，随即皱缩脱落．果实着色以后，就不再受浸染，但病果含糖量降低，品质变劣，易脱落．2发病规律此病一般在6月份发病，…     

大豆品种资源抗大豆花叶病(SMV)、灰斑病(Cercospora sojina)和霜霉病(Peronospora manschurica)的鉴定和评价

从1981—1986年对吉林、辽宁两省保存的大豆品种资源进行了抗大豆花叶病(SMV)、灰斑病(Cercospora sojina)和霜霉病(Peronospora manschurica)的抗性鉴定。结果在957个品种抗花叶病鉴定中,没有发现免疫品种,在1781个品种抗灰斑病鉴定中,对灰斑病免疫的品种81个,占4.5％;在1330个品种抗霜霉病鉴定中,对霜霉病免疫的品种有143个,占10.8％。所有参加鉴定的品种,没有对三种病同时免疫的。兼免疫灰斑病和霜霉病的品种7个,占0.5％,农家种灌水铁荚青在所有参加鉴定品种中表现抗花叶病、高抗灰斑病、免疫霜霉病,已收入大豆品种资源目录。可做为多抗性抗源,供抗病育种利用。     

玉米霜霉病及其检测技术研究进展

对玉米霜霉病的病原、症状、病害分布、病害传播与防治等基本特点进行了介绍。分析了近年来针对玉米不同霜霉菌在检测技术方面的研究新进展,包括菌体染色检测、同工酶检测和分子检测,以期为病害的进一步深入研究提供参考。     

大豆霜霉病抗源筛选的研究

大豆霜霉病是黑龙江省大豆产区主要病害之一。大豆因病减产约在6—15％。绥化农科所于1980—1985年采用病行诱发与人工接种方法对1300份材料进行了鉴定,共筛选出高抗材料319份,其中有一部分已作抗源应用于抗病育种工作,并从中选得70个有高度抗病力的新品系,绥78—5035(绥抗霉3号)就是一个高度抗病且抗性稳定的品系。经6年9个点次重复鉴定不发病,其它叶部病害也较轻。     

保护地黄瓜霜霉病的发生与防治

黄瓜霜霉病是黄瓜栽培生产中的流行性病害,分析了其发病规律,并从农业、生态和化学防治方面总结了防治技术和方法。     

厦门地区黄瓜霜霉病的发生与综合防治技术

霜霉病是黄瓜生产的主要病害之一,危害性大,常造成大面积减产,甚至绝收。通过介绍黄瓜霜霉病的危害症状、发生规律及综合防治技术措施,对推动黄瓜种植产业的发展具有重要意义。     

大豆霜霉病

大豆霜霉病,Peronospora manshurica(Naum.) Syd.ex G(?)um.是我国大豆Glycine max(L.)Merrill栽培区发生较普遍的病害,特别是在高湿生态区域危害较重。近年来随着大豆栽培方式的改变和种植面积的扩大,逐渐引起生产、研究等各方面的注意。     

向日葵霜霉病研究进展

向日葵霜霉病研究进展张德荣，李晓健（吉林市农业科学院植物保护研究所）向日葵霜霉病（Ｐｌａｓｍｏｐａｒａｈａｌｓｔｅｄｉｉ）是向日葵生产上的一种毁灭性病害［１］，可通过种苗、土壤和病残体传播［２，３，１２］。在适宜气候条件下，能使７０％－８０％的植株枯...     

双锦山葡萄抗霜霉病的调查研究

<正> 野生种山葡萄(Vifisamurensis RuPr)具有高度抗寒力,是抗寒育种的重要亲本。但最大的缺点是对霜霉病的抵抗力很弱。近几年来,我所选出的一个山葡萄新类型——双锦山葡萄(Vitis amnrensis RrnPr。Var.hermaphro, drta J.Y.Li)对霜霉病的抗性很强这对克服山葡萄在利用上的缺点是很重要     

Assessment of phenotypic diversity of Plasmopara viticola on Vitis genotypes with different resistance

The lack of characterized isolates of Plasmopara viticola is a very limiting issue in the management of downy mildew of grapevine. Although molecular studies have previously confirmed a high diversity of this pathogen, there are still no phenotypically characterized pathotype strains or races available which could be used to study the mechanisms of interaction with host genotypes of different resistance. A leaf disk inoculation technique was used to assess the variability of reactions of six different Vitis genotypes infected with single sporangial clones of five field isolates of P. viticola from different geographical origins. The virulence of thirty P. viticola clones was characterized on grapevine cultivars (Müller-Thurgau, Regent and Cabernet Cortis) and wild species (Vitis vinifera ssp. sylvestris, Vitis rupestris and Vitis riparia) with different susceptibility to downy mildew. Five categories ranging from full susceptibility with profuse and not clearly restricted sporulation (type A) to complete resistance with no sporulation or necrotic reaction (type E) were defined to evaluate the pathogen phenotype. A high variation of pathotypes was found amongst the samples from different field accessions and an unexpected variability was observed even between the cloned strains from the same field. This also accounted for the fungicide tolerance against the two most common fungicides, metalaxyl-M (Phenyl Amide group) and dimethomorph (Carboxylic Acid Amide group), where clones showing high sensitivity and high tolerance to the one or both fungicides were found within the same field. The virulence patterns found within clones of single field isolates supports previous reports that numerous genotypes may be involved in the infection of a single plant or even a single leaf. Moreover, the study provides a methodology to identify and select specific host–pathogen combination suitable for future studies in mechanisms of grapevine downy mildew interaction.     

Susceptibility to downy mildew (Plasmopara viticola) of different Vitis varieties

The susceptibility of different varieties of Vitis vinifera and other Vitis species to downy mildew (caused by Plasmopara viticola) in field, greenhouse and laboratory tests was compared over a period of three years. Different degrees of susceptibility were detected. The most susceptible V. vinifera varieties were ‘Treixadura’ and ‘Albariño; ‘Cabernet Sauvignon’, ‘Mencía’ and ‘Chasselas Doré’ were the least susceptible. The non-vinifera varieties showed no symptoms of downy mildew in the field. Surprisingly, in laboratory and greenhouse tests, the rootstock 110-R was much more susceptible to infection than S04. No relationship was seen between susceptibility and berry colour, or the time of sprouting or fruit ripening. Neither was any correlation seen between susceptibility and the condition of being a traditional or introduced variety. Better knowledge of the susceptibility to downy mildew of different varieties would allow for growers and breeders to select those that are more resistant.     

A bioeconomic model of downy mildew damage on grapevine for evaluation of control strategies

In order to reduce pesticide use in vineyards, we propose a bioeconomic model to evaluate different fungicide treatment strategies. This model estimates the development of the downy mildew Plasmopara viticola for a given year's weather on a grapevine plot, and predicts the damage done, the yield loss, and the resulting partial gross margin, depending on the chosen protection strategy.Grapevine growth and phenology are simulated with the STICS grapevine crop model according to the year's weather; fungal components quantify downy mildew development; damage onto leaves and fruits is characterized as a percent reduction of potential leaf area and yield; the effect of fungicide treatments is simulated as a partial protection against infection; the economic result is calculated at plot level, taking into account simulated yield, local economic conditions and costs of observations and sprayings.The model parameters were estimated using three sets of experimental data from vineyards in the French wine-growing region of Bordeaux. Using these parameter values, the model was used to evaluate the following five protection strategies: 3 systematic fungicide spraying strategies with 2-, 3- or 4-week intervals, the “Mildium” adaptive strategy, which includes field observations and decision rules, and a control untreated strategy. Yield losses and the resulting partial gross margins were calculated for 23 annual weather examples for each strategy and the statistics of these strategies were compared. The adaptive strategy was found to be slightly less protective on average against downy mildew than the 2-week systematic spray strategy. However its low variability ensures sustainability in terms of grower's income, while reducing by one third the number of sprayings. The model hypotheses and simulation results are discussed, in relation to the particular economic context of the “Bordeaux” protected designation of origin with the objective of reducing pesticide use in vineyards.     

The control of isariopsis leaf spot and downy mildew in grapevine cv. Isabel with the essential oil of lemon grass and the activity of defensive enzymes in response to the essential oil

The aim of this study was to evaluate the potential of the essential oil of lemon grass (Cymbopogon citratus) for the control of isariopsis leaf spot (Pseudocercospora vitis) and downy mildew (Plasmopara viticola) in grapevine cv. Isabel, the effect of the essential oil on the productivity of the grapevines and the effect of the essential oil on the activity of the enzymes chitinase and catalase. The experiment was conducted in a commercial vineyard over two consecutive crop cycles. Each plant in the experiment was subjected to one of the following nine treatments: 0, 0.5, 1.0, 2.0 or 4.0 mL L⁻¹ essential oil, Tween^® 80%, Bordeaux mixture, Acibenzolar-S-methyl and mancozeb. An analysis of the area under the disease progress curve showed a quadratic response by both diseases to the doses of essential oil during the first and second crop cycles. The essential oil treatments also increased the number and mass of the clusters of fruit as well as the productivity and desirable chemical characteristics of the grape. The activity of chitinase increased as a result of the essential oil treatments, whereas the activity of catalase decreased. The essential oil at doses of 1.0 and 2.0 mL L⁻¹ can serve as an alternative means of controlling isariopsis leaf spot and downy mildew and can also serve to improve the fruit quality of grapes cv. Isabel in tropical regions.     

Sensitivity,resistance stability,and cross-resistance of Plasmopara viticola to four different fungicides

Baseline sensitivity to fungicides was determined in 105 Plasmopara viticola isolates using the floating leaf disk test. The mean EC₅₀ values were 0.372 ± 0.104, 0.604 ± 0.215, 0.306 ± 0.101, and 0.922 ± 0.209 μg mL⁻¹ for fluxapyroxad, benthiavalicarb-isopropyl, ametoctradin, and famoxadone, respectively, which we regarded as the baseline sensitivity to the four fungicides. Resistant mutants can be generated using a median effective concentration or a minimum inhibitory concentration to fluxapyroxad, benthiavalicarb-isopropyl, ametoctradin, and famoxadone respectively, but the resistance stability of resistant mutants from the minimum inhibitory concentration (MIC) was significantly lower than that from the median effective concentration (EC₅₀). In brief, high resistant mutants obtained was at the higher concentration, the resistance stability of the mutants recovered was more quickly. But lower resistant mutants obtained was at the lower concentration, the resistance stability of the mutants recovered was slower. Even if the resistance level of the mutants is low, it is more capable of stably heritable. These data indicate that the highest dosage is not used, resistance will still develop. In a correlation analysis, no cross-resistance to each other of these four fungicides was observed.     

Simulating the susceptibility of clusters to grape black rot infections depending on their phenological development

In the years 2006–2008, clusters of Vitis vinifera (cv. Riesling) were inoculated with a conidia suspension of Guignardia bidwellii, the causal agent of grape black rot, at weekly intervals from one week before until eight weeks after bloom. Berries’ susceptibility turned out to be strongly linked to the speed of the phenological development in the respective season. In view of this, a degree day-based model simulating the relative susceptibility as a function of the phenological development was established. Infections on inflorescences were already possible prior to bloom. The period of highest susceptibility for direct infection on berries lasted from fruit set to the beginning of bunch closure. Successful infections took place until the end of bunch closure. Ontogenic resistance occurred clearly before veraison. Consequently, control measures should focus on the period between directly prior to bloom and bunch closure. Thus, the time span of black rot control coincides with the period in which vineyards need to be protected against the two major grape pathogens, Erysiphe necator and Plasmopara viticola. Applications of fungicides aimed at powdery and downy mildew control, also effective against G. bidwellii (e.g. strobilurins, triazoles and dithiocarbamates), offer a simultaneous control strategy for these three fungal diseases.     

Are there alternatives to copper for controlling grapevine downy mildew in organic viticulture?

Downy mildew caused by the obligate biotrophic oomycete Plasmopara viticola is one of the most important and devastating diseases of grapevine. Copper-based fungicides are used to control the disease in organic vineyards. However, since 2006, copper use has been limited by an European Commission regulation. In this study conducted from 2004 to 2007, we tested materials that might replace copper in organic viticulture, under controlled greenhouse and field conditions at two locations in Europe (northern Italy and Switzerland). We tested 112 different treatments, including biocontrol agents, materials of animal origin, homeopathic preparations, inorganic materials, microbial extracts, natural derivatives, plant extracts, physical methods and synthetic materials. Good control results were observed for two new copper formulations, but one of them induced phytotoxic effects. Two of the plant extracts provided good control on both leaves and clusters, and six of them controlled the infection on clusters only. One biocontrol agent reduced symptoms on leaves and bunches. Three of the other treatments provided good control on leaves, and four of them provided good control on bunches. Clay was as effective as copper on both leaves and bunches. Currently, even if there is no treatment that is as effective as copper for controlling grapevine downy mildew in organic vineyards, Yucca schidigera and Salvia officinalis extracts and Trichoderma harzianum, could be considered as promising candidates to be developed. This study may help the development of an integrated management program in which a less effective product is applied in combination with copper, to reduce the total quantities of copper applied.     

6个鲜食葡萄品种在云南元谋的引种表现

对引进的‘沈农金皇后’、‘沈农香丰’、‘沈农硕丰’、‘香妃’、‘26-3-4’和‘火洲黑玉’6个鲜食葡萄品种的物候期、果实经济性状和抗病性进行观察。结果表明，‘26-3-4’品种在元谋地区表现良好，成熟较早、颜色鲜艳及耐储运，适合在元谋地区大面积栽培发展；‘火洲黑玉’品种成熟早、可溶性固形物含量高及耐储运，但果粒质量较小，抗霜霉病和白粉病弱，‘沈农金皇后’、‘沈农香丰’、‘沈农硕丰’和‘香妃’4个品种果穗小、果粒软及不耐运输，不适宜在元谋地区大面积推广种植。     

Multilocation evaluation and selection of stable genotypes for reaction to downy mildew in pearl millet

Twenty-five pearl millet (Pennisetum typhoides (Burm. f.) Stapf and Hub. = P. americanum (L.) K. Schum.) genotypes were evaluated for resistance to downy mildew (Sclerospora graminicola (Sacc.) Schroet.) at 10 different locations in India and Africa during 1979 and 1980. The objective of this work was to identify genotypes with stable and generalized resistance. Genotypic differences in linear regression coefficients were found and regression lines for downy mildew incidence in the various genotypes tended to converge. It was concluded from this that selection on the basis of disease severity would enable genotypes that are superior at all disease levels to be selected. Seven genotypes, namely 700516, 700651, J-1486 × 700787-2-10, P-7, EB-83-2, NC-7174 and SSC-7218, showed low disease scores, average regressions and non-significant deviations, and therefore expressed stable, generalized resistance. Genotype 700251 was particularly suitable for high-disease environments. BJ-104, an important Indian hybrid cultivar, was very unstable and susceptible to downy mildew.     

大豆霜霉病(Peronospora manschurica)抗病性遗传分析

本研究于田间以种植感病品种病粒为感染行,并以田间采集的菌孢子进行接种的方法,对1984年配制的4个杂交组合和1988年配制的4个杂交组合与5个回交组合的F_1、F_2、F_3和B_1代抗感病性进行研究。调查分析表明:大豆霜霉病是由单基因控制的简单遗传,F_1代抗病性为完全显性,F_2代抗病单株与感病单株按3:1分离F_3代出现抗病系和抗病分离系,两类系的比例为1:2。F_1代与感病亲本回交,回交一代抗病与感病单株分离比例为1:1。F_1代与抗病亲本回交,回交一代表现抗病。