Nathalie Ollat

• PhD
• Engineer at French National Institute for Agriculture, Food, and Environment (INRAE)

Just over 150 years ago, grape phylloxera, Daktulosphaera vitifoliae, was introduced to Europe from North America via imports of plant material. This aphid-like insect has spread rapidly to most vineyards, causing rapid and lethal decline of Vitis vinifera. What happened in the second half of the 19 th century in response to this pest has shaped th...

Background The addition of bacteria and arbuscular mycorrhizal fungi (AMF) is a strategy used to protect plants against disease and improve their growth and yield, known as biocontrol and biostimulation, respectively. In viticulture, the plant growth promotion (PGP) potential of bacteria endemic to vineyard soil has been underexplored. Furthermore,...

Adaptation to drought is one of the most important challenges for agriculture. The root system, and its integration with the soil, is fundamental in conferring drought tolerance. At the same time, it is extremely challenging to study. The result is that investigations aimed at increasing crop drought tolerance have mainly focused on above-ground tr...

Rootstocks are potentially important levers of adaptation in the context of climate change. In this study, we investigated the effect of the rootstock and its genetic background on plant mineral status. The scion, the rootstock, and their interactions had a significant influence on petiole mineral content and explained the same proportion of phenot...

The past decade has produced some major advances in our understanding of how grapevines regulate their water use and tolerate drought. Numerous traits that are important for conferring drought tolerance have been identified and quantified across a range of cultivars (Dayer et al., 2022). Nevertheless, arriving at a firm hierarchical rating of diffe...

Rootstocks are an important means of adapting grapevine to environmental conditions whilst conserving the typical features of scion genotypes. Rootstocks not only provide tolerance to Phylloxera, but also ensure the supply of water and mineral nutrients to the scion. We take advantage of the large diversity of rootstocks used worldwide to facilitat...

Plants are able to naturally graft or inosculate their trunks, branches and roots together, this mechanism is used by humans to graft together different genotypes for a range of purposes. Grafts are considered successful if functional vascular connections between the two genotypes occur. Various techniques can evaluate xylem connections across the...

Plants are able to naturally graft or inosculate their trunks, branches and roots together, this mechanism is used by humans to graft together different genotypes for a range of purposes. Grafts are considered successful if functional vascular connections between the two genotypes occur. Various techniques can evaluate xylem connections across the...

In woody perennial plants, quantitative genetics and association studies remain scarce for root-related traits, due to the time required to obtain mature plants and the complexity of phenotyping. In grapevine, a grafted cultivated plant, most of the rootstocks used are hybrids between American Vitis species (V. rupestris, V. riparia, and V. berland...

Root-knot nematodes (RKNs) Meloidogyne spp. are extremely polyphagous pests and four species severely affect grapevines throughout the world: M. arenaria, M. incognita, M. javanica and M. ethiopica. Californian populations of M. arenaria and M. incognita are reported to be virulent to widely used rootstocks and to the rootstock ‘Harmony’ in particu...

In grafted plants, such as grapevine, increasing the diversity of rootstocks available to growers is an ideal strategy for helping plants to adapt to climate change. The rootstocks used for grapevine are hybrids of various American Vitis, including V. berlandieri. The rootstocks currently use in vineyards are derived from breeding programs involvin...

French research on rootstocks is based on two strategies: the creation of new rootstocks and the evaluation of existing rootstocks (GreffAdapt facility). The search for traits associated with drought tolerance has not yet been brought to a successful conclusion, but work is continuing with the emphasis on field experiments, measurement of δ13C, con...

To sustainably adapt viticultural production to drought, the planting of rootstock genotypes adapted to a changing climate is a promising means. Rootstocks contribute to the regulation of scion vigor and water consumption, modulate scion phenological development and determine resource availability by root system architecture development. There is,...

We elucidate grapevine evolution and domestication histories with 3525 cultivated and wild accessions worldwide. In the Pleistocene, harsh climate drove the separation of wild grape ecotypes caused by continuous habitat fragmentation. Then, domestication occurred concurrently about 11,000 years ago in Western Asia and the Caucasus to yield table an...

Grapevine decline affects viticulture worldwide. It is caused by a wide range of individual and combined biotic and abiotic factors. Some declines remain unexplained because they are not associated with known pathological symptoms or mineral dysregulation. Vineyard microbiological quality is an important area of study, since grapevine-associated mi...

Grafting is a traditional horticultural technique that makes use of plant wound healing mechanisms to join two different genotypes together to form one plant. In many agricultural systems, grafting with rootstocks controls the vigour of the scion and/or provides tolerance to deleterious soil conditions such as the presence of soil pests or pathogen...

Combining two different plants together through grafting is one of the oldest horticultural techniques. In order to survive, both partners must communicate via the formation of de novo connections between the scion and the rootstock. Despite the importance of grafting, the ultrastructural processes occurring at the graft interface remain elusive du...

Grapevine is severely affected by two major nepoviruses that cause grapevine degeneration: the grapevine fanleaf virus (GFLV) and the arabis mosaic virus (ArMV), specifically transmitted by the dagger nematodes Xiphinema index and X. diversicaudatum, respectively. While natural resistance to X. index has been shown to be a promising alternative for...

Soil microbiota plays a significant role in plant development and health and appears to be a major component of certain forms of grapevine decline. A greenhouse experiment was conducted to study the impact of the microbiological quality of the soil and grapevine rootstock genotype on the root microbial community and development of young plants. Two...

Evaluating the potential climatic suitability for premium wine production is crucial for adaptation planning in Europe. While new wine regions may emerge out of the traditional boundaries, most of the present-day renowned winemaking regions may be threatened by climate change. Here, we analyse the future evolution of the geography of wine productio...

En France, plus de 90 % de la production des vins est signalée par des « appellations », c’est-à-dire des indications géographiques, AOP ou IGP, qui garantissent que la qualité ou certaines caractéristiques de ces vins sont liées à leurs origines géographiques, et, dans le cas des AOP, à un terroir et des savoir-faire locaux reconnus. Mais le chan...

To optimize vineyard management practices to adapt viticulture to climate change, knowledge of the regulation mechanism of metabolite accumulation under carbon source limitation and abscisic acid (ABA) application in grapes should be deepened. Here, carbon source limitations were imposed by reducing leaf area from 12 to 2 leaves per vine (at pea si...

The production of grafted grapevine plant material is a complex process with many steps running over at least one year, from grafting to final sorting in nurseries. To reach the market in France, grafted grapevines must meet three criteria by law: resistance to a manual graft union test (or thumb test), a minimum number of three roots and a woody,...

Soil microbiota has increasingly been shown to play an integral role in viticulture resilience. The emergence of new metagenomic and culturomic technologies has led to significant advances in the study of microbial biodiversity. In the agricultural sector, soil and plant microbiomes have been found to significantly improve resistance to environment...

Grafting is an important horticultural technique used for many crop species. However, some scion/rootstock combinations are considered as incompatible due to poor graft union formation and subsequently high plant mortality. The early identification of graft incompatibility could allow the selection of non-viable plants before planting and would hav...

Conference at the international exhibition on "vine and wine technologies" (SITEVI), presenting the main outcomes of the LACCAVE project (adaptation to climate change in the wine industry)

Despite recent progress in our understanding of graft union formation, we still know little about the cellular events underlying the grafting process. This is partially due to the difficulty of reliably targeting the graft interface in electron microscopy to study its ultrastructure and three-dimensional architecture. To overcome this technological...

Abstract The dagger nematode Xiphinema index has a major economic impact due to its transmission of Grapevine fanleaf virus (GFLV) to grapevines. This vector nematode, which was introduced into Western countries from the Middle East together with the domesticated grapevine, mostly reproduces by meiotic parthenogenesis, but microsatellite multilocus...

Grapevine decline is a top concern in viticulture worldwide and is often associated with many biotic and abiotic factors. Grape trunk diseases and viruses are some of the most frequently identified causes of vine dieback. However, a decline is sometimes observed when no mineral deficiency or excess, or pathogenic causes can be identified. Soil enzy...

Despite recent progress in our understanding of the graft union formation, we still know little about the cellular events underlying the grafting process. This is partially due to the difficulty of reliably targeting the graft interface in electron microscopy to study its ultrastructure and three-dimensional architecture. To overcome this technolog...

Background and Aims Climate change is modifying grape berry composition and affecting wine quality and typicity. We evaluated the effects of leaf-to-fruit ratio and exogenous abscisic acid (ABA) application on the accumulation of primary and secondary metabolites in berries, in order to optimise climate change adaptation strategies. Methods and Re...

Etant donné les spécificités locales de la viti-viniculture française, en partie liées aux conditions climatiques, le changement climatique est un défi majeur que les acteurs de cette filière doivent relever régionalement. Pour explorer les stratégies d’adaptation à cette échelle, l’article combine deux approches : i ) une description et simulation...

L'article rend compte du forum de prospective organisé en 2019 par INRAE et InterLoire pour explorer les futurs possibles des vignobles du Val de Loire face au changement climatique. 90 acteurs de la filière ont exprimé leurs perceptions des conséquences du changement climatique en 2050, opté pour un scénario d’adaptation et proposé des leviers d’a...

Breeding for varieties carrying natural resistance (R) against plant-parasitic nematodes is a promising alternative to nematicide ban. In perennial crops, the long plant-nematode interaction increases the risk for R breaking and R durability is a real challenge. In grapevine, the nematode has a high economic impact by transmitting (GFLV) and, to de...

Background: Grafting is widely used in horticulture and rootstocks are known to modify scion growth and adaptation to soil conditions. However, the role of scion genotype in regulating rootstock development and functioning has remained largely unexplored. In this study, reciprocal grafts of two grapevine genotypes were produced as well as the corr...

A key determinant of plant resistance to vascular infections lies in the ability of the host to successfully compartmentalize invaders at the xylem level. Growing evidence supports that the structural properties of the vascular system impact host vulnerability towards vascular pathogens. The aim of this study was to provide further insight into the...

Background: Muscadine (Muscadinia rotundifolia) is known as a resistance source to many pests and diseases in grapevine. The genetics of its resistance to two major grapevine pests, the phylloxera D. vitifoliae and the dagger nematode X. index, vector of the Grapevine fanleaf virus (GFLV), was investigated in a backcross progeny between the F1 res...

Muscadine (Muscadinia rotundifolia) is known as a resistance source to many pests and diseases in grapevine. The genetics of its resistance to two major grapevine pests, the phylloxera D. vitifoliae and the dagger nematode X. index, vector of the Grapevine fanleaf virus (GFLV), was investigated in a backcross progeny between the F1 resistant hybrid...

Breeding for varieties carrying natural resistance (R) against plant-parasitic nematodes is a promising alternative to nematicide ban. In perennial crops, the long plant-nematode interaction increases the risk for R breaking and R durability is a real challenge. In grapevine, the nematode Xiphinema index has a high economical impact by transmitting...

The necessity to adapt to climate change is even stronger for grapevine than for other crops, because grape berry composition—a key determinant of fruit and wine quality, typicity and market value— highly depends on “terroir” (complete natural environment), on vintage (annual climate variability), and on their interactions. In the same time, there...

Background: Muscadine (Muscadinia rotundifolia) is known as a resistance source to many pests and diseases in grapevine. The genetics of its resistance to two major grapevine pests, the phylloxera D. vitifoliae and the dagger nematode X. index, vector of the Grapevine fanleaf virus (GFLV) was investigated in a backcross progeny between the F1 resis...

Muscadine ( Muscadinia rotundifolia ) is known as a resistance source to many pests and diseases in grapevine. The genetics of its resistance to two major grapevine pests, the phylloxera D. vitifoliae and the dagger nematode X. index , vector of the Grapevine fanleaf virus (GFLV) was investigated in a backcross progeny between the F1 resistant hybr...

Background: Grapevine is a crop of major economic importance, yet little is known about the regulation of shoot development in grapevine or other perennial fruits crops. Here we combine genetic and genomic tools to identify candidate genes regulating shoot development in Vitis spp. Results: An F2 population from an interspecific cross between V....

Background and aims: In most viticultural areas of the world, Vitis vinifera grapevines require grafting onto phylloxera-tolerant rootstocks of American origin. The species most commonly used in rootstock creation are Vitis berlandieri, V. riparia and V. rupestris. Rootstocks not only provide tolerance to phylloxera but also ensure the supply of wa...

Background: Muscadine (Muscadinia rotundifolia) is known as a resistance source to many pests and diseases in grapevine. The genetics of its resistance to two major grapevine pests, the phylloxera D. vitifoliae and the dagger nematode X. index, vector of the Grapevine fanleaf virus (GFLV) was investigated in a backcross progeny between the F1 resis...

Backgrounds and aims: Grapevine, Vitis vinifera, requires grafting on Phylloxera tolerant rootstocks of American origin in most viticultural areas of the world. The most commonly used species in rootstock creation are V. berlandieri, V. riparia and V. rupestris. Rootstocks not only provide tolerance to Phylloxera but assure the supply of water and...

Background: Grafting with rootstocks is essential for the culture of many perennial fruit crops and is increasing being used in the production of annual fruits and vegetables. Our previous work based on microarrays showed that transcripts encoding enzymes of both primary and secondary metabolism were differentially expressed during graft union for...

An amendment to this paper has been published and can be accessed via a link at the top of the paper

Grape growers have always cultivated vineyards in challenging environments, adapting their practices to sometimes very difficult local conditions. Climate change, as a new player, is modifying the terroirs’ characteristics rapidly and irremediably, giving viticulturalists major new challenges to face.

Muscadine ( Muscadinia rotundifolia ) is known as a resistance source to many pests and diseases in grapevine. The genetics of its resistance to two major grapevine pests, the phylloxera D. vitifoliae and the dagger nematode X. index , vector of the Grapevine fanleaf virus (GFLV) was investigated in a backcross progeny between the F1 resistant hybr...

Climate change will impose increasingly warm and dry conditions on vineyards. Wine quality and yield are strongly influenced by climatic conditions and depend on complex interactions between temperatures, water availability, plant material, and viticultural techniques. In established winegrowing regions, growers have optimized yield and quality by...

As the climate changes, genetic adaptation of crops to abiotic stresses is an increasingly important issue, especially for a perennial crops of high economic value such as grapevine. Given the numerous environments where this plant can be found, and the huge intra- and interspecific diversity, we can assume that grapevine genomes contain many aile...

A comprehensive analysis of all the possible impacts of future climate change is crucial for strategic plans of adaptation for viticulture. Assessments of future climate are generally based on the ensemble mean of state-of-the-art climate model projections, which prefigures a gradual warming over Europe for the 21st century. However, a few models p...

Foliar nutrition is one of the efective cultural practices in vineyards. In this research, the efect of iron chelate (Fe-EDDHA) and urea, each in three levels of 0, 0.5 and 1%, was evaluated with an ANOVA completely randomized block in commercial vineyard (cv “Sultana”) located in Bahareh village of Malayer city (Iran). Vines were sprayed in three...

Aims: Climate change imposes increasingly warm and dry conditions in most winegrowing regions. Mediterranean vineyards are particularly vulnerable and have registered, in most situations, declining yields over the past years. Although a majority of Mediterranean vineyards are still dry-farmed, yields can be increased by the implementation of irriga...

Foresight studies are regularly conducted at sectoral or geographical scales, in order to help policy makers and economic actors to define their strategy of adaptation to climate change (CC).

41. World Congress of Vine and Wine

The growth of a fleshy fruit is greatly affected by the carbon and water status of the parent plant. Here, we developed an integrated functional-structural grapevine (Vitis vinifera L.) model that can simultaneously simulate berry growth and whole-plant carbon and water status based on hourly environmental conditions. The model was tested on fruiti...

Grafting has been utilized for at least the past 7000 years. However, historically grafting has been developed by growers without particular interest beyond the agronomical and ornamental effects, thus knowledge about grafting has remained largely empirical. Much of the commercial production of fruit, and increasingly vegetables, relies upon grafti...

The growth of fleshy fruits is still poorly understood resulting from the complex integration of water and solute fluxes, cell structural properties, and the regulation of whole plant source-sink relationships. To unravel the contribution of these processes on berry growth, a biophysical grape (Vitis vinifera L.) berry growth module was developed a...

Adaptation to abiotic stresses is a complex and challenging biological issue for a genetician, especially for perennial plants such as grapevine. According to Copper and Hammer (1996), adaptation is both a “status” and a “process”. The “status” characterizes a genotype with a specific combination of alleles which allows the plant to survive and per...

In viticulture, grafting is used to facilitate grapevine cultivation in soils infected with phylloxera, a soil-dwelling insect pest introduced to Europe from America at the end of the 19th century. Successful grafting of plants is a complex biochemical and structural process that begins with an initial wound response, followed by callus formation a...

Regulation of root system growth and architecture is an adaptive mechanism evolved by plants to cope with variable nitrogen availability in the soil. In grafted plants, this process depends on intrinsic properties of the rootstock as well as long-distance signaling between each partner of the graft (scion and rootstock) and contributes to the fitne...