Evidence of Resistance to the Downy Mildew Agent Plasmopara Viticola in the Georgian Vitis Vinifera Germplasm

Total Page:16

File Type:pdf, Size:1020Kb

Evidence of Resistance to the Downy Mildew Agent Plasmopara Viticola in the Georgian Vitis Vinifera Germplasm Vitis 55, 121–128 (2016) DOI: 10.5073/vitis.2016.55.121-128 Evidence of resistance to the downy mildew agent Plasmopara viticola in the Georgian Vitis vinifera germplasm S. L. TOFFOLATTI1), G. MADDALENA1), D. SALOMONI1), D. MAGHRADZE2), P. A. BIANCO1) and O. FAILLA1) 1) Dipartimento di Scienze Agrarie e Ambientali, Università degli Studi di Milano, Milano, Italy 2) Scientific – Research Center of Agriculture, Tbilisi, Georgia Summary ability during late spring and summer usually prevent the spread of the disease (VERCESI et al. 2010). The control of Grapevine downy mildew, caused by Plasmopara downy mildew on grapevine varieties requires regular appli- viticola, is one of the most important diseases at the inter- cation of fungicides. However, the intensive use of chemicals national level. The mainly cultivated Vitis vinifera varie- becomes more and more restrictive due to human health ties are generally fully susceptible to P. viticola, but little risk and negative environmental impact (BLASI et al. 2011). information is available on the less common germplasm. Damages due to P. viticola could be reduced by using The V. vinifera germplasm of Georgia (Caucasus) is char- resistant grapevine varieties. The breeding programs are acterized by a high genetic diversity and it is different usually carried out by crossing V. vinifera with resistant from the main European cultivars. Aim of the study is species and in particular with American Vitaceae that co- finding possible sources of resistance in the Georgian evolved with the pathogen. The first generation hybrids, autochthonous varieties available in a field collection in obtained from the end of the XIXth to the beginning of the northern Italy. The resistance levels to P. viticola were XXth century, were unsuitable for the production of high estimated both by experimental inoculations and by quality wines, due to their unpleasant foxy aromas coming disease assessment in field conditions in a multi-year from the American species of the Vitis genus (EIBACH and activity. Of the 93 tested accessions, 'Mgaloblishvili N' TÖPFER 2015). Nowadays, thanks to numerous backcrossing showed a constant resistant behaviour, by reducing the cycles, the last generation breeding varieties possess resist- disease severity and the pathogen sporulation. High ant characteristics of the American species and qualitative levels of leaf hair density did not always associate with characteristics similar to those of V. vinifera cultivars (DI reduced disease gravity in experimental inoculations, GASPERO and FORIA 2015). However, finding sources of re- confirming that this kind of preformed barrier is not sistance in V. vinifera could be a great innovation, because it completely efficient in preventing pathogen infections. could really simplify the breeding programs originating new varieties with the quality levels required for wine production. K e y w o r d s : grapevine; disease resistance; disease Interesting results concerning the European wild grape, a incidence. subspecies of the V. vinifera species, have been recently found (SCHRÖDER et al. 2015). The V. vinifera species comprises cultivated (V. vinif- Introduction era subsp. vinifera) and wild (V. vinifera subsp. sylvestris Gmelin) subspecies, originally dispersed from western Asia Plasmopara viticola (Berk. & M. A. Curtis) Berl. & to Europe (ZOHARY and HORF 2000). At present, more than De Toni is a biotrophic pathogen which causes downy 12,000 accessions are recorded as individual cultivated vari- mildew to members of the family Vitaceae, in particular to eties in Europe (Vitis International Variety Catalogue-VIVC; the cultivated species Vitis vinifera L. (BELLIN et al. 2009). http://www.vivc.de/index.php). The origin of most of them P. viticola was fortuitously introduced in France from North is still questionable due to: the existence of several putative America during the nineteenth century and rapidly spread domestication centers, dispersed in all the distribution area across Europe (GALET 1977). The pathogen infects all green of the wild progenitor; exchange of plant material among parts of the plant causing, in favourable weather conditions, countries; and possible crossing among locally domesticat- extensive losses in grape yield (YU et al. 2012). The dam- ed varieties and grapes imported from abroad. Georgia in ages caused by the pathogen can lead to quantitative losses, the South Caucasian region, is considered one of the most by infecting inflorescences and bunches, and to qualitative important primary centers of domestication of cultivated losses, by causing an early defoliation of the plant. grapevine, in the larger area comprising Oriental Anatolia, Severe epidemics of downy mildew usually occur in Syria and Northern Mesopotamia, where the first viticulture temperate regions, characterized by grapevine vegetative emerged, towards the middle of the VI millennium BC seasons with frequent rainfall and moderate temperatures. (FORNI 2012). Actually paleobotanical and archaeological On the contrary, high temperatures and reduced water avail- remains attesting the first development of the vinicultural Correspondence to: Dr. S. L. TOFFOLATTI, Dipartimento di Scienze Agrarie e Ambientali, Università degli Studi di Milano, Milano, Via Giovanni Celoria 2, 20133 Milano, Italy. E-mail: [email protected] © The author(s). This is an Open Access article distributed under the terms of the Creative Commons Attribution Share-Alike License (http://creative-commons.org/licenses/by-sa/4.0/). 122 S. L. TOFFOLATTI et al. production and grapevine domestications have been found in some interesting Georgian varieties showed a high level Southern Caucasus; moreover, the region is rich in grapevine of resistance to P. viticola in experimental inoculations diversity and wild grapevines are widely present in the area (BITSADZE et al. 2015). (MAGHRADZE et al. 2012a). The main objective of the study was searching possible The evaluation of Georgian grapevine germplasm is sources of resistance to P. viticola in Caucasian V. vinifera interesting for different reasons. This germplasm comprises a germplasm coming from Georgia and cultivated in a field very wide range of cultivars (525 according to KETSKHOVELI collection in northern Italy by combining two approaches: et al. 1960) with high genetic variability (DE LORENZIS et al. experimental inoculations of leaf discs and evaluation of the 2015) and various ampelographic characters, agronomical disease incidence in vineyard. traits and phenological diversity (MAGHRADZE et al. 2012b). The viticultural and the enological features of this genetic material are also very different from Western European Material and Methods material (IMAZIO et al. 2013) and interesting because of their possible cultivation for innovative wine quality profiles, P l a n t m a t e r i a l : The 94 Georgian grapevine which could be different compared to wines from Western varieties used in this study (Tab. 1) are grown in in a collec- cultivars. There is also an interest in possible sources of tion vineyard established in 2006 at the Regional Research useful genes for breeding programs for qualitative char- Station of Riccagioia in Lombardy region of northern Italy. acters and/or for tolerance to biotic and abiotic stresses They are all V. vinifera varieties native to Georgia (South (MAGHRADZE et al. 2012b, QUAGLINO et al. 2016). Indeed, Caucasus region) apart from one: a Vitis x labruscana L.H. Table 1 List of Georgian varieties in relation to their region of origin, berry colour and density of the hairs between the veins on the lower side of the leaf ID Name of variety Region of origin Berry colour* Hair density** L21A Okroula Kakheti B 3 L21B Tsnoris Tetra Kakheti B 3 L21C Kurkena Kakheti B 3 L21D Akhmetis Shavi Kakheti N 3 L21E Saperavi Grdzelmtevana Kakheti N 3 L21F Zakatalis Tsiteli Kakheti N 3 L22A Mgaloblishvili Imereti N 7 L22B Marguli Sapere Imereti N 5 L22C Gabekhouri Tsiteli Imereti N 7 L22D Endeladzis Shavi Imereti N 3 L22E Mtsvane Onidan Ratcha B 5 L22F Usakhelouri Ratcha N 3 L23A Khushia Shavi Imereti, Guria N 7 L23B Orona Guria N 5 L23C Ikaltos Tsiteli Kakheti N 7 L23D Okhtoura Kakheti N 7 L23E Kistauris Saghvine Kakhuri N 5 L23F Vertkvichalis Shavi Imereti N 5 L24A Satsuravi Adjara N 7 L24B Khrogi Ratcha N 3 L24C Zakatalis Tetri Kakheti B 5 L24D Mtsvivani Mskhvilmartsvala Kakheti B 3 L24E Jghia Kakheti N 5 L24F Chinuri Kartli B 3 M21A Ghvinis Tsiteli Kakheti N 3 M21B Kharistvala Shavi Kakheti N 3 M21C Tkupkvirta Kakheti N 3 M21D BudeshuriTsiteli Kakheti N 3 M21E Buera Kakheti B 3 M21F Goruli Mtsvane Kartli B 7 M22A Zerdagi Samegrelo N 7 M22B Paneshi Samegrelo N 5 M22C Chkhucheshi Samegrelo B 3 M22D Chkhaveri Guria N 7 M22E Kamuri Shavi Guria N 5 M22F Jani Bakhvis Guria N 5 M23A Tkbili Kurdzeni Kakheti N 7 M23B Kuprashviliseuli Imereti N 7 M23C Dzelshavi Obchuri Imereti N 3 Resistance to Plasmopara viticola in the Georgian Vitis vinifera germplasm 123 Tab. 1, continued ID Name of variety Region of origin Berry colour* Hair density** M23D Mirzaanuli Kakheti B 3 M23E Chkhikoura Imereti B 3 M23F Kapistoni Tetri Imereti B 3 M24A Asuretuli Shavi Kartli N 3 M24B Tavkara Kakheti N 7 M24C Argvetula Imereti N 7 M24D Vitis x labruscana Georgia N 7 M24E Ananura Kartli N 3 M24F Tchvitiluri Samegrelo B 7 N21A Gorula Kartli B 3 N21B Tita Kartlis Kartli B 3 N21C Adreuli Tkhelkana Kartli N 5 N21D Shavkapito Kartli N 5 N21E Ghrubela Kartlis Kartli B 3 N21F Buza Kartli N 5 N22A Otskhanuri Sapere Imereti N 7 N22B Orbeluri Ojaleshi Lechkhumi
Recommended publications
  • Rpv Mediated Defense Responses in Grapevine Offspring Resistant to Plasmopara Viticola
    plants Technical Note Rpv Mediated Defense Responses in Grapevine Offspring Resistant to Plasmopara viticola Tyrone Possamai 1 , Daniele Migliaro 2,* , Massimo Gardiman 2 , Riccardo Velasco 2 and Barbara De Nardi 2 1 Department of Agricultural, Food, Environmental and Animal Sciences, University of Udine, via delle Scienze 206, 33100 Udine, Italy; [email protected] 2 CREA - Research Centre for Viticulture and Enology, viale XXVIII Aprile 26, 31015 Conegliano (TV), Italy; [email protected] (M.G.); [email protected] (R.V.); [email protected] (B.D.N.) * Correspondence: [email protected] Received: 30 May 2020; Accepted: 20 June 2020; Published: 22 June 2020 Abstract: Downy mildew, caused by the biotrophic oomycete Plasmopara viticola, is one of the most serious grapevine diseases. The development of new varieties, showing partial resistance to downy mildew, through traditional breeding provides a sustainable and effective solution for disease management. Marker-assisted-selection (MAS) provide fast and cost-effective genotyping methods, but phenotyping remains necessary to characterize the host–pathogen interaction and assess the effective resistance level of new varieties as well as to validate MAS selection. In this study, the Rpv mediated defense responses were investigated in 31 genotypes, encompassing susceptible and resistant varieties and 26 seedlings, following inoculation of leaf discs with P. viticola. The offspring differed in Rpv loci inherited (none, one or two): Rpv3-3 and Rpv10 from Solaris and Rpv3-1 and Rpv12 from Kozma 20-3. To improve the assessment of different resistance responses, pathogen reaction (sporulation) and host reaction (necrosis) were scored separately as independent features.
    [Show full text]
  • Determination of Downy Mildew and Powdery Mildew Resistance of Some Grape Cultivars
    Determination of Downy Mildew and Powdery Mildew Resistance of Some Grape Cultivars A. Atak Department of Viticulture, Ataturk Horticulture Central Research Institute, Yalova, Turkey Submitted for publication: June 2016 Accepted for publication: October 2016 Key words: Vitis spp., disease severity, resistance, inoculation, natural infection Different grape cultivars of Vitis species have been cultivated in Turkey since ancient times. A large proportion of these cultivars cannot be cultivated in the humid regions of the country due to downy mildew (Plasmopara viticola) and powdery mildew (Uncinula necator or syn. Erysiphe necator) diseases. Cultivars resistant to these diseases can generally grow without any or fewer fungicide applications. However, there are also differences in the resistance level of cultivars. In particular, Vitis vinifera cultivars, the most widely cultured species, are most affected by these diseases. Thirteen V. vinifera cultivars, eight V. labrusca cultivars and six interspecific cultivars were used in this study, for a total of 27 cultivars. The resistance of cultivars against downy mildew and powdery mildew was determined over two years with natural infection and artificial inoculation applications. Generally, all cultivars showed more resistance to downy mildew, while they also showed lower resistance to powdery mildew. The evaluation based on species found V. vinifera to be the most sensitive. While interspecific cultivars were found to be most resistant to downy mildew, V. labrusca cultivars were the most resistant to powdery mildew. Among cultivars of the same species, however, differences in terms of resistance were observed. These differences can be used in breeding studies in order to obtain new, disease-resistant cultivars, which may be grown commercially to comply with good agricultural practices (GAP) or organic viticulture in the future.
    [Show full text]
  • Elicitation of Grapevine Defense Responses Against Plasmopara Viticola , the Causal Agent of Downy Mildew
    Elicitation of grapevine defense responses against Plasmopara viticola , the causal agent of downy mildew Dissertation zur Erlangung des Doktorgrades (Dr. rer. nat.) der Naturwissenschaftlichen Fachbereiche der Justus-Liebig-Universität Gießen Durchgeführt am Institut für Phytopathologie und Angewandte Zoologie Vorgelegt von M.Sc. Moustafa Selim aus Kairo, Ägypten Dekan: Prof. Dr. Peter Kämpfer 1. Gutachter: Prof. Dr. Karl-Heinz Kogel 2. Gutachterin: Prof. Dr. Tina Trenczek Dedication / Widmung I. DEDICATION / WIDMUNG: Für alle, die nach Wissen streben Und ihren Horizont erweitern möchten bereit sind, alles zu geben Und das Unbekannte nicht fürchten Für alle, die bereit sind, sich zu schlagen In der Wissenschaftsschlacht keine Angst haben Wissen ist Macht **************** For all who seek knowledge And want to expand their horizon Who are ready to give everything And do not fear the unknown For all who are willing to fight In the science battle Who have no fear Because Knowledge is power I Declaration / Erklärung II. DECLARATION I hereby declare that the submitted work was made by myself. I also declare that I did not use any other auxiliary material than that indicated in this work and that work of others has been always cited. This work was not either as such or similarly submitted to any other academic authority. ERKLÄRUNG Hiermit erklare ich, dass ich die vorliegende Arbeit selbststandig angefertigt und nur die angegebenen Quellen and Hilfsmittel verwendet habe und die Arbeit der anderen wurde immer zitiert. Die Arbeit lag in gleicher oder ahnlicher Form noch keiner anderen Prufungsbehorde vor. II Contents III. CONTENTS I. DEDICATION / WIDMUNG……………...............................................................I II. ERKLÄRUNG / DECLARATION .…………………….........................................II III.
    [Show full text]
  • Downy Mildew 2018
    Downy Mildew The recent weather pattern was a big relief for many dryland farmers in Texas, but for grape growers in the eastern half of the state and especially the Gulf Coast, tropical moisture in the summer can spell big problems with downy mildew. Downy is one of few fungal diseases that can cause serious damage all season long, and each year we hear at least one report of total crop loss from downy. The warm and wet conditions this week have been ideal for downy mildew infections so if you have already seen downy in your vineyard this year then there is an extremely high probability of a reoccurring infection. If you have not seen downy mildew yet this year, there is a still a very good chance that an infection can or already has occurred. Even a very small, unnoticeable infection can explode into an outbreak under the right conditions. Make sure that your vineyard is properly protected! Young berries are highly susceptible to direct infections by downy mildew, but become increasing resistant with age. However, downy can infect all of the green parts of a grapevine season long. Infections this time of the year can lead to significant defoliation which in turn can severely reduce fruit quality and vine health. Favorite vineyard defoliated from downy mildew infection. The foliar symptoms of downy can vary quite a bit based on cultivar and tissue age so know what to look for when you are scouting your vineyard. You can visit the Texas A&M AgriLife Extension Viticulture & Enology webpage to view a photo gallery with more than fifty photos of downy mildew infections.
    [Show full text]
  • Extension Plant Pathology Update
    Extension Plant Pathology Update April 2013 Volume 1, Number 3 Edited by Jean Williams-Woodward Plant Disease Clinic Report for March 2013 By Ansuya Jogi and Jean Williams-Woodward The following tables consist of the commercial and homeowner samples submitted to the plant disease clinics in Athens and Tifton for March 2013 (Table 1) and one year ago in April 2012 (Table 2). Sample numbers are starting to pick up, but many of the problems we’ve seen in March were due to abiotic disorders such as cultural and/or environmental stresses (i.e. cold injury, past drought stress, poor root growth, etc.). Likely, the recent colder temperatures have slowed plant growth and plant disease development. We did have a few interesting samples, including cedar rusts and bulb mites on tulip (see pages 6 and 7). Looking ahead based upon April samples from last year and current weather conditions, we could expect more fungal leaf spot diseases, fire blight, rust, powdery mildew and downy mildew diseases. Table 1: Plant disease clinic sample diagnoses made in March 2013 Sample Diagnosis Host Plant Commercial Sample Homeowner Sample Arborvitae Decline; Dieback, Abiotic disorder Azalea Cultural/Environmental Problem, Abiotic disorder Bentgrass Anthracnose (Colletotrichum cereale) Blueberry Colletotrichum sp./spp. Cultural/Environmental Problem, Unknown, General Abiotic disorder Boxwood Root Problems, Abiotic disorder Camelia Camellia Petal; Flower Blight (Ciborinia camelliae) Root Problems, Abiotic disorder Environmental Stress; Problem, Abiotic disorder Tea
    [Show full text]
  • Fungal Disease Control
    Prevention and Management of Grape Fungal Diseases Close to Harvest Fungal disease of Grapevines Commonalities • Overwintering Inoculum – Mummies – Canes/Spurs – Trunks/Bark – Floor • Substrate – Green tissue – Juice Progression from One to Another Powdery Mildew Wounds Leaks Bunch Rots Powdery Rot Mildew Organism Spores Spores Cultural Controls • Sanitation – Remove infected material from the vineyard – Burn it – Uneconomical in California production vineyards – Air quality issues – We need some innovations/techniques/technologies to make this possible Cultural Controls • Sanitation – Removal/burning • Hot spots? – Invest resources in worst area(s) • Small blocks? – At least some areas have reduced spore loads • Small vineyards? – That’s why they can do it in France • Different blocks/areas every year? • Most susceptible varieties? • Areas upwind? Environmental Factors • Air Flow • Light • Moisture • Humidity Manipulating Environmental Factors • Canopy Management • Irrigation Management • Fertility Management Consider treating downwind as well as infected area Powdery Mildew • Even “inconspicuous” PM infections are associated with increased severity of Botrytis at harvest • And therefore, wine spoilage organisms Dangers of Losing Control Year 1 Spring Discharge of Spring Spore Load Overwintering Spore Compared to Final Spore Treatment Final Spore Load* Load** Load Previous Year A- Stop sprays at Labor day 1,300 260 - B- Stop sprays in August 5,300 1,060 80% of A C- Stop sprays in July 28,700 5,740 108% of B, 441% of A *Chasmothecia **Assuming
    [Show full text]
  • Downy Mildew Controlu Hofmann.Pdf
    “Optimisation of downy mildew (Plasmopara viticola) control in organic viticulture with low copper doses, new copper formulations and plant strengtheners, results of 20 years of on farm research” Hofmann, U.1, ECO-CONSULT, Geisenheim, Germany Key words: viticulture, downy mildew, copper formulations, Myco-Sin VIN, Potassium- Phosphonat (phosphorous acid). Abstract Since 20 years in different wine growing regions in Germany, due to weather and infection conditions several fungicide (copper formulations) and plant strengtheners (Myco-Sin VIN®, Ulmasud®, Frutogard®), different plant extracts and compost extracts applications against downy mildew are required in order to obtain satisfactory disease control. Results of the 20 years of on farm trials confirmed good efficacy of the copper based substances like copper hydroxide, partly in combination with two or three applications of Potassium Phosphonat, (Frutogard ®,) new copper-hydroxide formulation or copper oxychloride used in a low doses of copper, copper-octanuat (Cueva®) and alternative products like Myco-Sin-VIN® (sulphuric clay-limestone with high aluminium content). Introduction An organic vineyard is a complex living system where the grower actively tries to encourage the self regulation of the ecosystem and the health of this organism. In organic viticulture one of the primary goals is to grow healthy and disease tolerant or resistant plants. With the help of plant strengtheners, which are accepted by organic standards, and with the correct soil- and plant management the regulation of fungal diseases through the induction and enhancement of the plant’s own defence mechanisms, can be approached. Only as a last step chemical fungicides (copper and sulphur) are used to manage fungal problems.
    [Show full text]
  • Mechanism of Powdery Mildew Infection in Grapevines
    Mechanism of powdery mildew infection in grapevines FINAL REPORT to GRAPE AND WINE RESEARCH & DEVELOPMENT CORPORATION Project Number: CRV 02/07N Principal Investigator: Dr Ian B. Dry Research Organisation: Cooperative Research Centre for Viticulture Date: 29th June 2006 Project Title: Mechanism of powdery mildew infection in grapevines CRCV Project Number: 3.1.5 Period Report Covers: July 2002 – June 2006 Author Details: Dr Ian Dry CSIRO Plant Industry Postal address: PO Box 350, Glen Osmond, SA 5064, Australia Phone: 08 83038632 Fax: 08 83038601 Mobile: Email: [email protected] Date report completed: June 2006 Publisher: Cooperative Research Centre for Viticulture ISBN OR ISSN: Copyright: © Copyright in the content of this guide is owned by the Cooperative Research Centre for Viticulture. Disclaimer: The information contained in this report is a guide only. It is not intended to be comprehensive, nor does it constitute advice. The Cooperative Research Centre for Viticulture accepts no responsibility for the consequences of the use of this information. You should seek expert advice in order to determine whether application of any of the information provided in this guide would be useful in your circumstances. The Cooperative Research Centre for Viticulture is a joint venture between the following core participants, working with a wide range of supporting participants. Table of Contents Abstract ……………………………………….… 2 Executive summary ……………………………………....…. 3 Copy of Matt Hayes PhD thesis Appendix 1: Communication Appendix 2: Intellectual Property Appendix 3: References Appendix 4: Staff Appendix 5: Publications Appendix 6: Budget reconciliation Abstract This study has provided new insights into the molecular and biochemical processes associated with the powdery mildew:grapevine interaction.
    [Show full text]
  • Early Season Grape Disease Management, Spring 2020 Katie Gold Assistant Professor, Cornell University Cornell Agritech Geneva, NY 14456 [email protected]
    Early Season Grape Disease Management, Spring 2020 Katie Gold Assistant Professor, Cornell University Cornell AgriTech Geneva, NY 14456 [email protected] What is the value of early season disease management? Early season grape disease control is critical for season long protection. Most grape pathogens prefer soft, succulent tissues and immature berries. If disease is allowed to take hold during the early season, late season control will become near to impossible at worst, and incredibly challenging (and expensive) at best. Early season disease control pays for itself. Management in the early season in New York primarily focuses on five diseases: phomopsis, black rot, downy mildew, powdery mildew, and anthracnose. Grapevine varieties differ in their susceptibility to these diseases, but generally speaking, native American varieties are least susceptible, vinifera are the most susceptible, and hybrid varieties are intermediate. This article will introduce the five main early season diseases that affect grapevine in New York, discuss cultural practices that can reduce disease inoculum in vineyards, and outline the basics of a strong early season spray program from dormancy until pea-sized fruits. A follow up article will address late season management from pea-sized fruits to harvest. As a reminder, growers on Long Island should check labels to ensure recommended products in this article are labeled for use on Long Island. What are we managing for? Phomopsis: Phomopsis is a significant problem on Concord and Niagara grapes, though hybrid and V. vinifera grapes are susceptible as well. Phomopsis can infect all succulent tissue on grapevines when conditions are favorable. Infections that occur on the developing rachis when clusters first become visible at about 3” shoot growth are most damaging and can result in severe fruit loss.
    [Show full text]
  • Mildew (Peronospora Sparsa)
    A review into control measures for blackberry downy mildew (Peronospora sparsa) Guy Johnson and Ruth D’Urban-Jackson ADAS Boxworth, Battlegate Road, Cambridgeshire, CB23 4NN Background Control of downy mildew in commercial blackberry production is becoming increasingly difficult. Losses of effective spray control products in recent years, particularly close to harvest, have exacerbated the problem. Novel and alternative approaches will be required in future. AHDB has already funded several projects to assess new control measures, but this desk study aims to identify additional ideas. Summary of main findings • Use of protected cropping to reduce leaf wetness will help minimise infection • Good site selection to maximise light interception, maintain good air movement and avoid natural sources of infection is important • Maintain good air movement by removing weed growth in the crop vicinity and managing the crop to avoid excessive vegetative growth • Reduce relative humidity below 85%. The use of air fans in glasshouse crops improves air movement • Manage nitrogen application carefully to avoid excessive leaf growth • Photoselective polythene to alter the wavelength of light reaching the crop could affect the infection rate, but this requires further study • The efficacy of the currently approved biopesticide control agents Serenade ASO, Sonata, Amylo X and Prestop requires further assessment • Elicitors (such as potassium phosphite) and plant extracts are known to offer varying levels of control, but these need further screening to assess
    [Show full text]
  • Plasmopara Viticola Infection Affects Mineral Elements Allocation And
    www.nature.com/scientificreports OPEN Plasmopara viticola infection afects mineral elements allocation and distribution in Vitis vinifera leaves Stefano Cesco1, Anna Tolotti1, Stefano Nadalini2, Stefano Rizzi2, Fabio Valentinuzzi1, Tanja Mimmo1,3, Carlo Porfdo4, Ignazio Allegretta4, Oscar Giovannini5, Michele Perazzolli5,6, Guido Cipriani2, Roberto Terzano4, Ilaria Pertot5,6 & Youry Pii1* Plasmopara viticola is one of the most important pathogens infecting Vitis vinifera plants. The interactions among P. viticola and both susceptible and resistant grapevine plants have been extensively characterised, at transcriptomic, proteomic and metabolomic levels. However, the involvement of plants ionome in the response against the pathogen has been completely neglected so far. Therefore, this study was aimed at investigating the possible role of leaf ionomic modulation during compatible and incompatible interactions between P. viticola and grapevine plants. In susceptible cultivars, a dramatic redistribution of mineral elements has been observed, thus uncovering a possible role for mineral nutrients in the response against pathogens. On the contrary, the resistant cultivars did not present substantial rearrangement of mineral elements at leaf level, except for manganese (Mn) and iron (Fe). This might demonstrate that, resistant cultivars, albeit expressing the resistance gene, still exploit a pathogen response mechanism based on the local increase in the concentration of microelements, which are involved in the synthesis of secondary metabolites and reactive oxygen species. Moreover, these data also highlight the link between the mineral nutrition and plants’ response to pathogens, further stressing that appropriate fertilization strategies can be fundamental for the expression of response mechanisms against pathogens. Grapevine is one of the most important crops worldwide, for production of fresh fruits, raisins, juices and wine1 and, within the genus Vitis, V.
    [Show full text]
  • Aphanomyces Euteiches Laurent Camborde
    Fuctional characterization of different candidate effectors from the root rot oomycete Aphanomyces euteiches Laurent Camborde To cite this version: Laurent Camborde. Fuctional characterization of different candidate effectors from the root rot oomycete Aphanomyces euteiches. Vegetal Biology. Université Paul Sabatier - Toulouse III, 2020. English. NNT : 2020TOU30227. tel-03208760 HAL Id: tel-03208760 https://tel.archives-ouvertes.fr/tel-03208760 Submitted on 26 Apr 2021 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Abstract Oomycetes are eukaryote pathogens able to infect plants and animals. During host interaction, oomycetes secrete various molecules, named effectors, to counteract plant defence and modulate plant immunity. Two different classes of cytoplasmic effectors have been described to date, Crinklers (CRNs) and RxLR proteins. The translocation process allowing the entrance into the host cells is still unclear, and while extended research gave insight into some molecular targets and role during infection, most of effectors have not been characterized. In the root rot pathogen of legumes Aphanomyces euteiches, only the CRNs are present. Based on a previous study reported by our research group, we published an opinion paper focused on the emergence of DNA damaging effectors and their role during infection.
    [Show full text]