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Background and aims Beginning in the last two decades of the 14th century, richly illuminated versions of the Tacuinum Sanitatis, the Latin translation of an 11th-century Arabic manuscript known as Taqwim al-Sihha bi al-Ashab al-Sitta, were produced in northern Italy. These illustrated manuscripts provide a window on late medieval life in that region by containing some 200 full-page illustrations, many of which vividly depict the harvest of vegetables, fruits, flowers, grains, aromatics and medicinal plants. Our objective was to search for and identify the images of taxa of Cucurbitaceae and Solanaceae. Methods We have located all reported illustrated Tacuinum Sanitatis and similar or related manuscripts, searched through printed or electronic reproductions of them, categorized six of them that display full-page illustrations as archetypic, and established the identity of the Cucurbitaceae and Solanaceae appearing in these six manuscripts. Key results and conclusions Of the Cucurbitaceae, Cucumis sativus (short-fruited cucumbers), Cucumis melo (including round as well as elongate melons), Citrullus lanatus (both sweet watermelons and citrons), and Lagenaria siceraria (including bottle-shaped as well as long gourds), are illustrated. Of the Solanaceae, Solanum melongena (egg-shaped purple aubergines) and Mandragora sp. (mandrake) are illustrated. These depictions include some of the earliest known images of cucumber, casaba melon (Cucumis melo Inodorous Group) and aubergine, each of which closely resembles an extant cultivar-group or market type. Overall, the botanically most accurate images are in the version of the Tacuinum located in the Osterreichische Nationalbibliothek, Vienna, cod. ser. n. 2644. Similarities and differences in botanical accuracy among the images of Cucurbitaceae and Solanaceae in the six archetypal Tacuinum manuscripts suggest to us that another illustrated Tacuinum, now lost, may have antedated and served as a model or inspiration for the six surviving archetypic manuscripts.

International audience; Zoospores of 12 isolates O. bornovanus from geographically diverse sites and representing the three host specific cucurbit strains were tested as vectors for seven viruses using watermelon bait plants and the in vitro acquisition method. All isolates of the cucumber, melon, and squash strains transmitted melon necrotic spot carmovirus (MNSV) and cucumber necrosis tombusvirus (CNV) but none transmitted petunia asteroid mosaic tombusvirus (PAMV) or tobacco necrosis necrovirus (TNV). The isolates varied as vectors of three other carmoviruses: cucumber leaf spot virus (CLSV); cucumber soil borne virus (CSBV); and squash necrosis virus (SqNV). All cucumber isolates transmitted CLSV and SqNV but not CSBV. Some of the melon isolates transmitted CLSV and SqNV but none transmitted CSBV. Two squash isolates transmitted CSBV and SqNV but not CLSV. Two isolates of O. brassicae transmitted only TNV and a third did not transmit any of the viruses. The species of bait plant sometimes affected transmission. The most efficient vector strains of O. bornovanus, as determined by reducing zoospores and virus in the inoculum, were the cucumber strain for CLSV; the cucumber strain for CNV if cucumber was the bait plant or melon strain if watermelon was the bait plant; and the squash strain for SqNV. The plurivorous strain of O. brassicae was the most efficient vector of TNV. Olpidium bornovanus is the first vector reported for CSBV and is confirmed as a vector of SqNV. It is proposed that all carmoviruses may have fungal vectors. Ligniera sp. did not transmit any of the viruses in one attempt.

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International audience; During a survey conducted in October 2005, cucurbit leaf samples showing virus-like symptoms were collected from the major cucurbit-growing areas in Tunisia. DAS-ELISA showed the presence of Moroccan watermelon mosaic virus (MWMV, Potyvirus), detected for the first time in Tunisia, in samples from the region of Cap Bon (Northern Tunisia). MWMV isolate TN05-76 (MWMV-Tn) was characterized biologically and its full-length genome sequence was established. MWMV-Tn was found to have biological properties similar to those reported for the MWMV type strain from Morocco. Phylogenetic analysis including the comparison of complete amino-acid sequences of 42 potyviruses confirmed that MWMV-Tn is related (65% amino-acid sequence identity) to Papaya ringspot virus (PRSV) isolates but is a member of a distinct virus species. Sequence analysis on parts of the CP gene of MWMV isolates from different geographical origins revealed some geographic structure of MWMV variability, with three different clusters: one cluster including isolates from the Mediterranean region, a second including isolates from western and central Africa, and a third one including isolates from the southern part of Africa. A significant correlation was observed between geographic and genetic distances between isolates. Isolates from countries in the Mediterranean region where MWMV has recently emerged (France, Spain, Portugal) have highly conserved sequences, suggesting that they may have a common and recent origin. MWMV from Sudan, a highly divergent variant, may be considered an evolutionary intermediate between MWMV and PRSV

Mention d'édition : 3. ed.; International audience; Watermelon mosaic virus (WMV) and zucchini yellow mosaic virus (ZYMV) are two major potyviruses infecting cucurbits. WMV is the causal agent of one of the first described cucurbit mosaic virus diseases, while ZYMV emerged as a major cucurbit pathogen causing severe yield losses only in the late 1970s. WMV infects many weeds and several crops outside cucurbits while ZYMV has a more restricted host range. Both are efficiently transmitted by aphids in a nonpersistent manner, which often results in rapid and severe epidemics in the fields. Control measures rely mainly on prophylactic methods (weeding, mulching). Cross-protection has been developed commercially to control severe ZYMV isolates. Breeders using classical and genetically engineered resistance have already released WMV and ZYMV commercial resistant cultivars in the major cucurbit crops. Important biological variability is observed among ZYMV isolates and to a lesser extent among WMV isolates. The serological and molecular variability is also high. Molecular studies revealed that WMV probably arose through recombination between two legume-infecting viruses. In addition, intraspecific recombinations seem to be common in WMV. ZYMV is presently used as a biotechnological tool to produce in cucurbit plants proteins of pharmaceutical or plant protection interest.

Powdery mildew [Podosphaera xanthii (Castagne) Braun & Shishkoff (syn. Sphaerotheca fuliginea auct. p.p.)] is now a common disease on watermelon [Citrullus lanatus (Thunb.) Matsum. & Nakai] in the United States. In this study, the entire available U.S. Plant Introduction collection of Citrullus Schrad. ex Eckl. & Zeyh. species was evaluated for resistance to P. xanthii race 1W. The collection consists of four Citrullus species and one Praecitrullus Pangalo species [C. lanatus var. citroides (L.H. Bailey) Mansf., C. colocynthis (L.) Schrad., C. rehmii De Winter, and P. fistulosus (Stocks) Pangalo]. Wild-type accessions tended to be more resistant more often than the cultivated species, C. lanatus var. lanatus. None were immune, eight of the 1573 accessions exhibited high levels of resistance, and another 86 demonstrated intermediate resistance. Stem and leaf disease severity were weakly correlated (r 2 = 0.64, P = 0.001). The majority of accessions having resistance were collected in Zimbabwe. Resistance was found in four species.

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La mesure directe des remontées capillaires sous cultures pose de gros problèmes expérimentaux. La méthode proposée ici est basée sur une approche indirecte du phénomène. 1- Sur un site voisin du site expérimental, soumis à des conditions identiques (mesure du profil tensiométrique, et du profil de teneur en eau), et lorsqu'un gradient ascendant de potentiel s'est établi (début de saison sèche), on bâche brusquement le site de mesure, le mettant ainsi en conditions d'évaporation et de transpiration nulle. A l'aide d'un modèle mécaniste de transfert d'eau, on estime alors les paramètres d'une fonction décrivant les variations de la conductivité hydraulique en fonction du potentiel du sol, dans la gamme de potentiels sous lesquels s'opèrent les remontées capillaires sous le profil racinaire. 2- Par une expérimentation de drainage interne, on estime dans une gamme plus élevée de potentiels la conductivité, ce qui permet de disposer de celle-ci sur une gamme étendue, sous laquelle l'essentiel des processus de remontées capillaires opèrent. 3- On reprend les valeurs issues de ces mesures dans un modèle simulant par une approche mécaniste les transferts d'eau dans le sol sous culture, et on en déduit les différents termes du bilan hydrique, dont les remontées capillaires. Le travail présente les résultats expérimentaux menés au Nicaragua sur sols volcaniques, sous culture de sorgho, et appliqués à une culture de pastèque en saison sèche. On explique ainsi l'existence ancestrale de systèmes de cultures dont le principe consiste à effectuer un travail du sol créant les conditions de mise en marche d'une pompe à remontées capillaires

PI 525088-PMR is a watermelon (Citrullus lanatus var. lanatus) line having resistance to melon race one powdery mildew (PM) Podosphaera xanthii (syn. Sphaerotheca fuliginea auct. p.p.). The line is derived from the U.S. Plant Introduction (PI) 525088 (Citrullus lanatus var. lanatus). PI 525088PMR does not have desirable fruit quality with fruit flesh color being white to light pink and an average Brix value of 6. However, it could be a useful parent for introducing race one powdery mildew (P. xanthii) resistance into adapted watermelon cultivars.

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* INRA, URD, Domaine St Paul, Site Agroparc, 84914 Avignon cedex 9 Diffusion du document : INRA, URD, Domaine St Paul, Site Agroparc, 84914 Avignon cedex 9 Diplôme : Dr. d'Université

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Malgré l'importance économique de l'agriculture familiale au Nordeste du Brésil, les réseaux de collecte, de transformation et de commercialisation où elle s'insère sont mal connus. Pendant cette mission, un diagnostic des circuits locaux de commercialisation a été réalisé pour deux produits dont la structure de production est essentiellement familiale : le lait à Nossa Senhora da Gloria (Sergipe) et la pastèque dans les périmètres irrigués de Petrolina (Pernambouc). Les résultats montrent l'organisation complexe des réseaux de commercialisation. Ils permettent de formuler une proposition méthodologique pour le diagnostic rapide des systèmes de commercialisation dans le Nordeste

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International audience; A survey was conducted in eastern, central and western parts of the Sudan to determine the major viruses affecting various cucurbit crops (snake cucumber, melon, watermelon, and squash). Of 102 samples analyzed, using DAS-ELISA, nearly 65% were infected by cucurbit aphid-borne yellows luteovirus (CABYV), 54% by zucchini yellow mosaic potyvirus (ZYMV) and 39% by geminiviruses serologically related to watermelon chlorotic stunt virus (WCSV). Among other viruses identified, squash mosaic comovirus (SqMV) was detected in 15% of the samples, a potyvirus closely related to watermelon mosaic virus type Morocco (WMV-M) in 4% of the samples, cucumber mosaic cucumovirus (CMV) in 4% of the samples and melon rugose mosaic tymovirus (MRMV) in 2% of the samples.This is the first report of CABYV and ZYMV in the Sudan, and the first report of WCSV and MRMV in Africa.

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Parthenogenetic haploid embryos of `Crimson Sweet', `Halep Karasi', `Sugar Baby' and `Panonia F1' watermelon [Citrullus lanatus (Thunb.) Matsum. & Nakai] were obtained after pollination with γ-irradiated (200 or 300 Gy) pollen. Some globular and heart-shaped embryos were observed in fruit harvested 2 to 5 weeks after pollination. The number of embryos per 100 seeds was highest for `Halep Karasi'. After in vitro culture, 17 haploid plants were obtained and doubled haploid lines were generated after chromosome doubling using colchicine.

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7. congress of Kukem. Ankara (Turquie)

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International audience; In a survey of cucurbit crops in Sudan, 234 samples of melon, cucumber, and squash showing symptoms of powdery mildew were infected with Sphaerotheca fuliginea, while Erysiphe cichor-acearum was only observed on two samples of watermelon showing mild symptoms. Ieeveillula taurica was not observed on any sample. Field trials with differential lines of melon revealed the presence of race 1 of S. fuliginea in Gezira (Central Sudan) in the summer of 1993, and race 2 in the following winter. Virulence tests in controlled conditions on a limited number of isolates suggest that a shift in prevalence of those races may have occurred on that site over time. The geographic scale of this shift was probably limited as race 0 was observed in late autumn in northeast Sudan in the Gash Delta.

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En Guadeloupe, le virus 1 de la mosaïque de la pastèque, Papaya Ringspot Virus-Watermelon (PRSV-W)= Watermelon Mosaic Virus 1 (WMV-1), est très répandu dans les cultures de courgette où il provoque des symptômes de mosaïque avec cloques et des déformations filiformes très marquées sur le feuillage et également des déformations de fruits. Depuis 1982, on a constaté qu’un autre faciès maladif était aussi épidémique dans les champs de courgette. Il se distingue de celui de PRSV-W par une mosaïque donnant un aspect tigré au feuillage et l’absence de déformation filiforme. L’isolat (Q10) provenant de l’une des plantes infectées par la souche « Tigré » a été étudié. Le virus est transmissible par inoculation mécanique. Il est transmis par puceron sur le mode non persistant mais à un taux différent de celui observé pour le PRSV-W. Sa gamme d’hôtes est analogue à celle du PRSV-W. Elle est limitée à la famille des Cucurbitacées et en particulier, les génotypes de Cucumis melo, C. metuliferus, Cucurbita ecuaderensis et C. foetidissima résistants au PRSV-W sont aussi résistants à l’isolat Q10. Les particules virales sont flexueuses. L’infection induit dans le cytoplasme la formation d’inclusions amorphes et d’inclusions cylindriques se classant dans la subdivision I. Des tests sérologiques d’immunodiffusion en présence de dodécyl-sulfate de sodium et des tests en ISEM (Immunosorbent Electron Microscopy) ont montré que l’isolat Q10 ne réagissait avec aucun des sérums dont nous disposions préparés contre les virus suivants : PRSV-W, Watermelon Mosaic Virus 2 (WMV-2), Watermelon Mosaic Virus « Morocco » (WMV-M), Zucchini Yellow Mosaic Virus (ZYMV), Zucchini Yellow Fleck Virus (ZYFV). Inversement, PRSV-W, WMV2 et ZYMV n’ont pas réagi avec le sérum préparé spécifiquement contre l’isolat Q10. L’isolat Q10 a des propriétés biologiques proches de celles du PRSV-W ; il s’en distingue par son taux de transmission par puceron, sa symptomatologie sur certains hôtes et par ses propriétés sérologiques. Une étude complémentaire permettra d’établir si cet isolat doit être considéré comme un sérotype du PRSV-W ou comme un virus à part entière., In Guadeloupe, a Caribbean island, the watermelon strain of papaya ringspot virus (PRSV-W = watermelon mosaic virus 1, WMV-1) is commonly encountered in squash fields. It induces a severe mosaic with blistering and filiformism on squash leaves, and a deformation of fruits. Since 1982, a new disease has been found epidemically in squash fields, the symptoms being leaf discoloration according to a striped ("Tigre") pattern and limited filiformism. An isolate (Q10), collected from a squash showing the "Tigre" symptom, was studied. The virus was transmitted mechanically and also transmitted by aphids in the non-persistent manner and less efficiently than PRSV-W. Its host range was similar to that of PRSV-W. It was restricted to the Cucurbit family, and genotypes of Cucumis melo, C. metuliferus, Cucurbita ecuadorensis and C. foetidissima resistant to PRSV-W were also resistant to isolate Q10. Virus particles were filamentous. Infection induced in the cytoplasm the formation of amorphous and cylindrical type I inclusions. Sodium dodecyl sulfateimmunodiffusion and ISEM (Immunosorbent Electron Microscopy) tests showed that isolate Q10 did not react with sera prepared against the following viruses : PRSV, watermelon mosaic virus 2 (WMV-2) watermelon mosaic virus "Morocco" (WMV-M), zucchini yellow mosaic virus (ZYMV), zucchini yellow fleck virus (ZYFV). Conversely, PRSV-W, WMV-2 ans ZYMV did not react with the serum specifically prepared against isolate Q10. Some biological properties of isolate Q10 and PRSV-W were similar but the viruses could be distinguished by their aphid transmission rate, symptoms on some hosts and serological properties. Further studies will show whether this isolate should be considered as a new serotype of PRSV or as a new virus.