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An experiment is related in which well-fed tomato plants, grown within a rockwool tomato culture, were suddenly nourished with a nitrogen-free nutrient solution. For 6 weeks, control (+N) and treated (-N) plants were regularly harvested and analysed in order to determine the impact of the treatment on growth, yield and N composition of several organs. After 6 weeks of the treatment,-N plants had accumulated ca. 20% less dry biomass, mainly because of a reduced vegetative growth. Commercial fruit yield was slightly less affected by N-withdrawal, being decreased by 17%.-N plants invested less N than C in the growth of young fruits, leading to %N decrease in their dry biomass. N movements, mainly feeding fruits, have been characterised. In control plants, the efficiency of N-fertiliser use was low (46%) indicating important nitrate wastage in the drainage (> 1000 kg N⋅ha-1), harmful to the environment. Lycopersicon esculentum / critical N / environment / model / deficiency Résumé-Impacts d'une privation d'azote sur le rendement et le bilan azoté d'une culture de tomate sur laine de roche. Une privation d'azote a été pratiquée sur un lot de plantes au cours d'une culture de tomates sous serre. Pendant 6 semaines, des plants témoins et privés d'azote ont été prélevés et analysés pour determiner l'impact du traitement sur la croissance, le rendement et la composition des organes. Chez les plantes-N, on a observé 20 % d'accumulation de MS en moins après 6 semaine de traitement, majoritairement dus à une faible croissance végétative. Le rendement en fruits récoltés a lui aussi été affecté (-17 %). Pendant la privation, la plante a investi moins d'azote que de carbone dans la construction des jeunes fruits, impliquant une teneur moindre en azote. Des mouvements d'azote ont été caractérisés dans la plante, essentiellement vers les fruits. Chez les plantes +N, on a déterminé au cours du cycle cultural, un faible coefficient d'interception de l'engrais azoté (0,46), signifiant un fort rejet d'azote dans les drainages (>1000 kg⋅N ha-1), préjudiciable à l'environnement.

UMR 1334 AGAP : Equipe AFEF ‘Architecture et Fonctionnement des Espèces fruitières’ ; Team AFFS ‘Architecture and Functioning of Fruit Species’We performed an analysis of published literature related to fruit and vegetable and indexed in the Web of Science®, covering the period 2000–2009. The EU27 and the USA are the two leading actors in terms of number of fruit and vegetable articles published. This paper compares their publication outputs using bibliometric methods. We assessed the fruit and vegetable species, topics (from Web of Science® categories), countries and institutions involved. The top species, topics and institutions are ranked according to their number of publications. Collaboration networks between countries were mapped to visualize the intensity of the relationships involved in international fruit and vegetable research and to obtain an overall picture of the fruit and vegetable research landscape. These results can be useful for policy makers