News on resistance

First vine varieties resistant to diseases produced in Italy

They are ten: five white berries - Fleurta, Soreli, Sauvignon Kretos, Sauvignon Nepis, Sauvignon Rytos - and five red berries - Cabernet Eidos, Cabernet Volos, Merlot Khorus, Merlot Kanthus, Julius, the first disease-resistant grapevines variety, produced in Italy by researchers from the University of Udine and the Institute for Applied Genomics (IGA) in Udine. The new varieties, registered in the National Register of Vine Varieties on 3rd of  April 2015, were officially presented to the public and the press in January 2016 in Udine, in the presence of the delegate of the Minister of Agriculture, Food and Forestry, Salvatore Parlato, and the Regional Council Member for the Agricultural and Forestry Resources, Cristian Shaurli. The "magnificent ten", as the researchers from Udine call them, are the result of 15 years of research work and an extraordinary synergy between public and private sector. The biggest benefit of the new vine varieties will be the ability to dramatically reduce the costs of viticulture by saving on treatments.

Hundreds of crossbreeds were made through natural cross-breed and selection processes, tens of thousands of plants were evaluated, over 500 micro-vinification were repeated over the years at the Italian Wine Union in Verona and the Vivai Cooperativi di Rauscedo. These are just a few numbers of the project, launched in 1998, with the main aim of reducing the use of pesticides in this area of agricultural production and responding to the critical situation of viticulture in Europe, the most influential agricultural activity on the environment. While occupying only 3.3% of the agricultural area, viticulture accounts for 65% of all fungicides used in agriculture. In viticulture, in fact, production costs are noticeable due to a large number of interventions for the protection of vineyards, and the availability of varieties that do not require treatments is very attractive.

The crossbreeds were carried out at the Agricultural Company "Antonio Servadei" of the University of Udine, where over 24,000 crossbreed plants have been evaluated till today. Selected vineyards were evaluated by the University of Udine, in collaboration with the  Vivai Cooperativi di Rauscedo to which were granted exclusive distribution and marketing rights, regarding the experimental fields in Fossalon di Grado (GO), in Tuscany, in the Chianti area, and in the Slovenian Collio area. In 2015, the European and international patents covering were provided and the new varieties were included in the Italian national register at the Ministry of Agriculture Policies.



The genetic improvement of the grapevine

The genetic improvement of the vine has two sides: the one concerns table grapes, the other one concerns wine grapes. In the first case, traditional genetic improvement, based on crossbreed and selection, has been intense and has led to the spectacular enrichment of the varietal landscape. In the second case, we have witnessed a history of suffering, with programs that have produced few interesting novelties and, moreover, they have so far had a very marginal place in wine viticulture.

La ragione di questo scarso successo va cercata nella grande difficoltà per queste nuove varietà di uva da vino, frutto generalmente di incrocio tra genotipi all'interno di V. vinifera, di trovare un posto accanto a varietà molto note e celebrate, che abbinate al territorio di produzione hanno creato un connubio “cépage-terroir” (come dicono i francesi) difficile da scalfire.

The reason for this poor success is to be found in the great difficulty of these new varieties of wine grapes, generally generating from a crossbreed of the genotypes within V. vinifera, to find a place next to well-known and celebrated varieties that matched the territory of production and with which have created a  “cépage-terroir”  union (as the French say) difficult to scratch.

The combination of a vine and its cultivation environment was well known to the ancients. Plinio, in his monumental natural history, wrote that "some vines have such a love for their soil that leaves to them all their fame and can not be moved to any place without their quality being plagued" [Plinio, Naturalis Historia III, 2-26]. Following this concept, culturally and in some ways also biologically interesting, it has come to a wine viticulture that has selected wines and territories of great excellence over time but has also inhibited the compartment, making it unsustainable from the environmental point of view.

Viticulture in Europe occupies 3% of the agricultural area, but it accounts for 65% of all fungicides employed in agriculture, equal to 62,000 tonnes (Eurostat 2007). European viticulture has reasons to reflect on the fact that it has always postponed the renewal of varieties, as is the case for any other agricultural crop. Today, in many European countries, efforts are being made to reduce the use of pesticides in viticulture, in line with the more general guidelines of the Common Agricultural Policy (CAP) as regards environmental sustainability and consumer health. One of the ways to follow is certainly the creation of new varieties of resistant / ill-tolerant varieties, and this is the way the researchers from Udine have been following since their start in 1998 with a Crossbreed and Selection Program for the Creation of Wine Screws Resistant to Certain Diseases.


The genetic improvement of grapevine in Europe

To be honest, crossing programs and selection of the grapevine varieties for disease resistance began in Europe in the second half of the nineteenth century following the introduction of the New World by three pathogens - phylloxera, vine downy mildew and powdery mildew - which had devastated viticulture from the second half of the 19th century. The result of this activity was a series of varieties obtained by crossbreeding with species of American vines, but also Asiatic.

Of these varieties, first-generation hybrids (Clinton, Isabella, Noah, Bacò, Seyval, Villard Blanc, etc.) are well-known, but the "breeder's path" has been long. These first-generation varieties are followed by those of the second and then third and fourth generations, with which American "blood" has gradually been reduced in favour of the European"blood". Today we are faced with more than a hundred varieties and selections, which do not entirely remind us of the negative oenological characteristics of wild vines and, as the EU has decided a few years ago, can be cultivated in the countries of the Union. In this European context, the cross-sectional and selection process started by the University of Udine, assisted by the Institute for Applied Genomics, which had successfully participated in 2006 in the Italian-French sequencing of the genome of the grapevine.


The sources of resistance

With regard to the two fungal diseases considered (downy mildew and powdery mildew), the sources of resistance reported in the literature are numerous. The Udine group has so far worked with two monogenic downy mildew resistances (Rpv3, Rpv12), originating respectively from American and Asian species, and two monogenic powdery mildew resistances (Ren1 and Run1), the first of which has been identified in some varieties of 'vinifera' cultivated in some republics of Central Asia (Uzbekistan, Tajikistan, Dagestan, Moldova, Armenia, Russia, Georgia); The second is present in Muscadinia, a variety similar to variety Vitis, on which the French have been working in the past for several decades and the French researchers have been working on vinifera introgression as well. The fertile interspecific hybrids obtained at the beginning of the 20th century by Detjen, despite the different number of chromosomes that characterize the two species (2n = 38 for Vitis and 2n = 40 for Muscadinia) have allowed, with a series of successive crossings, to obtain Descendants with 2n = 38 chromosomal kit, fertile, with the RUN1 gene and interesting berry characteristics. Obviously, for the resistances identified in American and Asian vines, the work has not started from the wild species, but from the results of crossbreeds made by researchers from other countries such as Germany, France, Hungary, Austria, the Republic of Serbia and Uzbekistan.

These are advanced selections, some already being cultivated in different EU countries and outside Europe. The resistant selections used in crossings are Bianca, Regent, 20/3, Seyval, Pannonia, SK-00-1 / 2 and others. These are sometimes very complex "pedigree" varieties that reflect the great work done by foreign research institutes in 50 and sometimes more years of activity.


Crossing plans and selection activity

The plan initially included the crossing of some internationally renowned varieties such as Chardonnay, Sauvignon, Merlot, Cabernet Sauvignon,  national ones such as Sangiovese and local varieties such as the Friulian Tocai (today 'Friulano'), on one hand, and a series of varieties and advanced selections obtained from viticulture research centers mainly in continental Europe, among which the Geilweilerhof Viticulture Institute and the Geisenheim University in Germany should be reminded of the availability and value of the supplied material, The Pecs Institute of Viticulture and Enology in Hungary and the University of Novi Sad in Serbia.

Over fifteen years of activity, over 360 cross-over combinations have been tested, utilising dozens of valuable commercial varieties over time and over a dozen resistance genotypes over time. Second and third generation crossings were also performed, using as parents the children of the previous crosses with the purpose, as will be discussed later, to differentiate the product typology and to combine resistances from different varieties and selections. For each crossing combination, 100 to 2,000 seedlings were raised. For those who are not traders, the seedling (or progeny) is a plant obtained from seed, obtained in turn, in the case of crossing programs, through the controlled crossing. The seedlings were evaluated through a three-stage process. The first evaluation concerned resistance on some deseases; Individuals who were not resistant were excluded from the following stages. Resistant individuals, cloned on cloned rootstocks, were subjected to an agronomic assessment and nano- and micro-vinification was conducted on the best individuals.


Evaluation of resistance, agronomic and oenological evaluation

The evaluation mainly concerned resistance to downy mildew and, secondly, resistance to grey mildew. Two genes for dendritic downy mildew resistance and two genes for grey mildew resistance were worked out. In the early years, the selection of downy mildew resistant varieties was based on field observations on untreated plants and on laboratory observations carried out on leaf disks subjected to artificial inoculation with conical suspensions. In recent years, thanks to the sequencing work of the genome of the vine and to the mapping of the genome regions where the resistance genes are present, assisted selection techniques have been adopted, based on the analysis of DNA sequences of the regions that bring resistance or very close regions with absent or very low recombination rate.

This is a selection method known as Marker-Assisted Selection (MAS), which allows replacing field observations, long and sometimes unreliable, with the analysis of molecular markers associated with resistance genes. DNA analysis is possible when still seed-born plants are small at the stage of 2-3 true leaves. The advantages of this approach are obvious, which quickly eliminates unattractive plants by reducing field spaces for breeding crosses and thus reducing the timing and cost of the selection itself. One noteworthy advantage of molecular analysis is the ability to select, by means of an haplotype analysis of the resistance-bearing region, individuals who have maintained a very small part of the original chromosome of the original wildlife, thus eliminating regions that are not linked to resistance, which often carry unwanted characters.

The agronomic evaluation focused on plant vigour, the basal fertility of buds, productivity, shape and size of the cluster. Weak or excessively vigorous plants, those with low baseline gem strength, those with too low or too high productivity were eliminated. Particular attention has been given to the cluster, preferably selecting individuals with a spatula cluster or not too compact, as often the very compact bunch is subject to the rotation when ripening the grapes.

The oenological assessment: it is useful to recall in this context that a crossbreed does not rebuild the genome of a very heterozygous parent, as are the vine varieties. So the expectations of some winemakers to re-enter a Cabernet or a Sangiovese-resistant to diseases, are out of place. Nevertheless, as is the case of human being, where the children are not equal to any of their parents, but they remember the appearance and some traits of character, even in the vine some parents leave a more or less marked impression of their oenological attitudes in descent. Thus, the resistant Sauvignon children's selections often remind the parent of the presence in thiol and methoxypirazine wines; similarly, the children of Tocai Friulan are often characterized by the presence in the wine of norisoprenoids and terpenols, typical of the parent they come from.

The market and future prospects

Ten selections - 5 white berries and 5 red berries - were registered officially in 2015. Too many, someone will say. We say no, considering three aspects: the diversity of genetic backgrounds due to the use of different parents, the opportunity to leave the market the right to select the best varieties and the diversity of environments where new selections can be introduced. We believe that some selections are certainly suitable for Mediterranean environments, but considering their low-temperature resistance, some of these varieties can adapt well to colder climates, typical of Central Europe and Central Asia where the viticulture is a growing sector.

 Those on the market are crosses made mainly in the years 2002-2003, using a limited number of parents. Since then, researchers from the University of Udine and IGA have continued to perform new crossings with two goals:

  • Combine together different genes of resistance to the same pathogen, to make the resistances lasting;
  • Differentiate the product by orienting the choice of parentheses to produce varieties with a sparkling base, varieties suitable for ageing, aromatic varieties and desserts, etc.

In the meantime, the research for new sources of resistance continues, with the aim of providing a battery of genes that can cope with the pathogenesis of the pathogen, in which the selection of new breeds that can overcome genes resistance in commercial varieties. It's an endless business: a survival struggle - as Darwin says - in which the pathogen has to overcome the resistance of the host plant and the plant must create new resistance variants with the goal of surviving of both. The sources of resistance found in Asian species, for example in China (V. amurensis, V. betulifoliaV. chunganensisV. brevipedunculataV. romanetiiV. thumbergii, V. lanata and others), for which there are few accessions in the West.

Gabriele Di Gaspero, Patricija Muzlovic 




Related questions

  • One of the most important issues related to the introduction of GMOs is their food safety. People fear that genetic modification may lead to the introduction of products, in food chain, with potentially unpredictable side effects, so eating OGM foods may pose greater risks than traditional non-genetically modified foods on human health. Is that so?

    Riguardo alle biotecnologie e, in particolare all'introduzione di  organismi geneticamente modificati (OGM) nel settore agroalimentare, si è acceso negli ultimi anni un forte dibattito a livello nazionale e internazionale relativamente alle tematiche della protezione dell'ambiente e della salute, così come implicazioni economiche e sociali e questo nonostante ci sia ampio consenso in ambito scientifico nel ritenere che i cibi OGM non presentino rischi maggiori di quanti ne presenti il normale cibo. 

    Una delle fonti principali dove poter trovare informazioni sull'argomento è sicuramente EFSA, l’agenzia europea, istituita nel 2002, fonte indipendente di consulenza scientifica e comunicazione sui rischi associati alla catena alimentare. La legislazione alimentare generale ha creato un sistema europeo di sicurezza alimentare in cui la responsabilità di valutare i rischi e quella di gestirli sono tenute separate. L’agenzia che opera in modo indipendente dalla Commissione europea, dal Parlamento europeo e dagli Stati membri, è stata, ha di recente dedicato una sezione del proprio sito informativo proprio al tema OGM, sulle richieste di autorizzazione di OGM e sulla cooperazione con gli Stati membri dell'UE. Un'altra sezione illustra il quadro normativo che disciplina il lavoro dell'EFSA in tema di OGM.Già nel 2011 l'EFSA ha infatti avviato un progetto per valutare otto nuove tecniche di miglioramento di vegetali. Al gruppo di esperti scientifici è stato chiesto di valutare se i correnti documenti orientativi fossero ancora validi per piante sviluppate utilizzando le nuove metodiche che includevano intragenesi, cisgenesi e tecnica della nucleasi a dito di zinco (ZFN). Il gruppo di lavoro ha concluso che l’attuale guida alla valutazione del rischio (tra cui una guida alla valutazione dei rischi ambientali) era applicabile anche alla valutazione di alimenti e mangimi derivati tramite queste nuove tecniche. Nel 2013 la Commissione europea ha richiesto che l'EFSA sospendesse ulteriori valutazioni di nuove tecniche di miglioramento vegetale, per consentire al gruppo OGM di concentrarsi sulla valutazione di richieste di autorizzazione di OGM e sullo sviluppo di linee guida. Per i dettagli è possibile scaricare il pdf sottostante. 

    In Italia la discussione sulle nuove tecniche biotecnologiche, ed in particolare sulla cisgenesi e il genome editing è stata portata in senato il 30 luglio del 2015 come “Affare assegnato sulla materia delle nuove tecnologie in agricoltura, con particolare riferimento all'uso delle biotecnologie sostenibili e di precisione (Atto n. 591)”. Da allora fino a luglio 2016 la 9ª Commissione permanente (Agricoltura e produzione agroalimentare) ha eseguito nove sedute con audizioni di rappresentanti del Consiglio per la ricerca in agricoltura e l’analisi dell’economia agraria (CREA), appresentanti del Consiglio nazionale per le ricerche (CNR) del Presidente della Società italiana di biologia vegetale (SIBV) e del Presidente della Società italiana di genetica agraria (SIGA) di rappresentanti della Fondazione Edmund Mach di rappresentanti di Greenpeace Italia dell'Associazione italiana sementi (Assosementi) e di esperti vari (tra cui anche i ricercatori di IGA).

    Il mondo della ricerca sostiene che miglioramento genetico vegetale rappresenta uno dei settori attraverso i quali è possibile aumentare competitività e sostenibilità del sistema agricolo anche rispetto alle sfide della efficienza produttiva, dei cambiamenti climatici, della sostenibilità delle produzioni, con riferimento soprattutto alla riduzione dell’uso dei pesticidi. Tra le nuove tecniche biotecnologiche, quelle più promettenti e per le quali vi è un notevole interesse della comunità scientifica, sono la cisgenesi e il genome editing. Si tratta di tecnologie di recente messa a punto che permettono di modificare in modo mirato il patrimonio genetico di una varietà commerciale, frutto spesso di numerosi anni di breeding, riproducendo quanto avviene attraverso le mutazioni naturali o l’incrocio naturale (processi che sono alla base della struttura genetica delle moderne varietà coltivate di tutte le specie agrarie), ma in maniera rapida e selettiva. 

    ll miglioramento genetico vegetale rappresenta uno dei settori attraverso i quali è possibile aumentare competitività e sostenibilità del sistema agricolo anche rispetto alle sfide della efficienza produttiva, dei cambiamenti climatici, della sostenibilità delle produzioni, con riferimento soprattutto alla riduzione dell’uso dei pesticidi. Tra le nuove tecniche biotecnologiche, quelle più promettenti e per le quali vi è un notevole interesse della comunità scientifica, sono la cisgenesi e il genome editing. Si tratta di tecnologie di recente messa a punto che permettono di modificare in modo mirato il patrimonio genetico di una varietà commerciale, frutto spesso di numerosi anni di breeding, riproducendo quanto avviene attraverso le mutazioni naturali o l’incrocio naturale (processi che sono alla base della struttura genetica delle moderne varietà coltivate di tutte le specie agrarie), ma in maniera rapida e selettiva. 

    Patricija Muzlovic

  • What does precisely "varietal innovation" mean?

    L’innovazione varietale significa selezionare varietà che possono fornire produzioni di alta qualità con ridotto fabbisogno energetico ed a basso impatto ambientale e per rispondere alle esigenze sempre più eco-consapevoli dei consumatori. La Convenzione internazionale UPOV del 1991 definisce come “varietà” insieme di individui coltivati identificabili mediante l’espressione delle caratteristiche risultanti da un dato genotipo o da una combinazione di genotipi, che si distingue nettamente da un qualsiasi altro insieme vegetale per almeno una delle suddette caratteristiche e che dopo cicli di moltiplicazione successive conservi le proprie caratteristiche distintive. 

    L’Unione Internazionale per la Protezione delle Nuove Varietà Vegetali è  nata a seguito di una Convenzione, sottoscritta a Parigi nel 1961 appunto per la protezione delle nuove varietà di piante.  Entrata in vigore nel 1968, è stata poi oggetto di successive revisioni nel 1972, 1978 e 1991 (quest'ultimo in vigore dal 24/4/1998). Scopo dell'UPOV è quello di promuovere un efficiente sistema di protezione sui ritrovati vegetali ed assicurare che i membri dell'Unione riconoscano i risultati raggiunti dai costitutori vegetali, concedendogli un diritto di proprietà intellettuale. Inoltre assiste i paesi membri nel processo di implementazione nella propria legislazione nazionale. Attualmente (luglio 2011) aderiscono all'UPOV 70 paesi, fra cui anche l'Italia.

    Per essere idonee alla protezione, le varietà devono rispondere a requisiti di: novità e distinguibilità dalle varietà già esistenti, uniformità e stabilità. I costitutori vegetali (breeders) che operano in Italia hanno due possibilità alternative per tutelare le proprie novità vegetali:

    • tutela solo per l'Italia, con la protezione nazionale per le nuove varietà vegetali, attraverso il Decreto Legislativo 10 febbraio 2005, n.30;
    • tutela per tutto il territorio della Comunità Europea, con il regime comunitario di privativa per i ritrovati vegetali (Reg. (CE) 2100/94).
    Patricija Muzlovic