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[EN] Pot experiments were carried out to characterize the response of two Cucumis metuliferus accessions against (a)virulent Meloidogyne arenaria, M. incognita or M. javanica populations, to Mi1.2 gene and to determine the compatibility and the effect on physicochemical properties of cantaloupe melon. In addition, histopathological studies were conducted. Plants were inoculated in 200 cm3 -pots with 1 J2 cm-3 24 of soil containing sterilized sand a week after transplanting and maintained in a growth chamber at 25 ºC for 40 days. The susceptible cucumber cv. Dasher II or melon cv. Paloma were included for comparison. The number of egg masses and number of eggs per plant were assessed, and the reproduction index (RI) was calculated as the percentage of eggs produced on the C. metuliferus accessions respect those produced on the susceptible cultivars. The compatibility and fruit quality was assessed grafting three scions (two of Charentais type) and one of type Piel de Sapo under commercial greenhouse conditions. The resistance level of both C. metuliferus accessions ranged from highly (RI < 1%) to resistant (1% ¿RI ¿ 10%) irrespective of Meloidogyne populations. Melon plants grafted onto C. metuliferus accession BGV11135 grew as selfgrafted plants and did not modify negatively fruit quality traits. Giant cells induced by RKN on C. metuliferus were mostly poor developed compared to those on cucumber. Furthermore, necrotic areas surrounding the nematode were observed. C. metuliferus accession BGV11135 could be a promising melon rootstock to manage Meloidogyne spp. irrespective of its (a)virulent Mi1.2 condition without melon fruit quality reduction., This work was supported by AGL2013-49040-C2-1-R, and AGL2014-53398-C2-2-R projects from the Spanish Ministry of Economy, Industry and Competitiveness, and cofounded with FEDER Funds. The authors would like to thank Semillas Fito for providing melon cv. Paloma, Dr Christine Vos (Scientia Terrae Research Institute) for her English revision and critical comments of the manuscript and Dr Nuria Escudero (Universitat Politecnica de Catalunya) for her support and critical comments on the manuscript.

The influence of the squash hybrid RS841 rootstock (Cucurbita maxima x C. moschata) on population dynamics of Meloidogyne incognita and yield of cucumber cv. Dasher II was assessed during 2013 and 2014 in a plastic greenhouse. In addition, the relationship between ecophysiological parameters (plant water status, gas exchange, and leaf reflectance) and Pi and cucumber yield were also estimated in 2013. Nematode densities were determined at the beginning (Pi) and at the end (Pf) of each crop, and the relationship between these parameters was used to estimate the maximum multiplication rate (a), the maximum population density (M) and the equilibrium density (E) per grafted and ungrafted cucumber and cropping season. Moreover, the relationship between the multiplication rate (Pf/Pi) and Pi was compared between grafted and ungrafted cucumber per cropping season. Finally, the relative yield of grafted or ungrafted cucumber was plotted against Pi to determine the tolerance limit (T) and the minimum relative yield (m) by the Seinhorst damage function model. Values of a, M and E in grafted cucumber were higher than in ungrafted one irrespective of the cropping season. These results were supported by comparing the relationship between Pf/Pi and Pi between grafted and ungrafted cucumber. The relationship between Pi and yield fitted the Seinhorst damage function. The values of T and m did not differ between grafted and ungrafted each year. Predawn water potential, net photosynthetic rate, and leaf chlorophyll index decreased with increasing Pi. In addition, relative yield was related to variation in net photosynthetic rate and the leaf chlorophyll index. Under the conditions of this study, RS841 rootstock was neither resistant nor tolerant to M. incognita.

Contamination of fresh cucumbers (Cucumis sativus L.) with Escherichia coli O157:H7 can impact the health of consumers. Despite this, the pertinent mechanisms underlying E. coli O157:H7 colonization and internalization remain poorly documented. Herein we aimed to elucidate these mechanisms in cucumbers using an inverted fluorescence microscope and hyperspectral microscopy. We observed that E. coli O157:H7 primarily colonized around the stomata on cucumber epidermis without invading the internal tissues of intact cucumbers. Once the bacterial cells had infiltrated into the internal tissues, they colonized the cucumber placenta and vascular bundles (xylem vessels, in particular), and also migrated along the xylem vessels. Moreover, the movement rate of E. coli O157:H7 from the stalk to the flower bud was faster than that from the flower bud to the stalk. We then used hyperspectral microscope imaging to categorize the infiltrated and uninfiltrated areas with high accuracy using the spectral angle mapper (SAM) classification method, which confirmed the results obtained upon using the inverted fluorescence microscope. We believe that our results are pivotal for developing science-based food safety practices, interventions for controlling E. coli O157:H7 internalization, and new methods for detecting E. coli O157:H7-plant interactions.

Azospirillum brasilense is a well known plant growth-promoting rhizobacterium. Plant cell growth is constrained by the primary cell wall (CW) which contains polysaccharide-bound hydroxycinammic acids (HCAs). They derive from phenylpropanoid metabolism, which first step is the reaction catalyzed by phenylalanine ammonia-lyase (PAL; EC 4.3.1.24). Also CW peroxidases (FAPOD; EC 1.11.1.7) play a key role in the stiffening of the CW, and in the cessation of cell elongation. Knowledge of the biochemical effects the bacteria could elicit into plant CW and how these responses could change the hypocotyl physiology still remains scarce. The objective of this work was to unravel the effects of A. brasilense Sp245 inoculation on HCAs of the primary CW in apical and basal segments of cucumber seedlings hypocotyls. Azospirillum inoculation increased hypocotyls’ length. Transferulate and p-coumarate were the major HCAs. Dimmers were detected only in the basal region of 13- and 15-d-old hypocotyls. The ratio t-ferulate/dimmer (an inverse index of CW cross-linking) was five times higher in inoculated seedlings. Enzyme activities determined were not directly involved in HCAs content changes. It was previously reported that the CW was a target for A. brasilense growth promotion. This work corroborates that the phenolics, FA, DFA, and p-coumarate bound to the CW are also involved in Azospirillum plant growth promoting strategies. EEA Balcarce Fil: Dal Lago, Claudia Cristina. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agarias. Unidad Integrada. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Balcarce. Laboratorio de Bioquímica Vegetal y Microbiana; Argentina Fil: Creus, Cecilia. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Balcarce. Unidad Integrada. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agarias. Laboratorio de Bioquímica Vegetal y Microbiana; Argentina Fil: Pereyra, María Alejandra. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agarias. Unidad Integrada. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Balcarce. Laboratorio de Bioquímica Vegetal y Microbiana; Argentina

Many cucurbits, such as cucumbers, squashes and pumpkins, depend on pollinating bees in order to set fruit. However, fruit yield and progeny vigor in these plants generally decreases as heterospecific pollen deposition increases. We studied how the spatial area dedicated to cucumbers (Cucumis sativis), versus other flowering plants, influenced the deposition of conspecific and heterospecific pollen on cucumber plants in New York City community gardens. We also examined the effect of garden size on conspecific and heterospecific pollen deposition on cucumber plants. Female flowers were collected from potted cucumber plants that had been experimentally placed into the gardens, specifically for this study, or that were established in raised beds by members of the community garden. In the laboratory, pollen grains were isolated from the flower by acetolysis, and the number of heterospecific and conspecific cucumber pollen grains were quantified. Conspecific pollen deposition was positively and significantly associated with the size of a community garden, as well as with the area of each garden dedicated to non-cucumber, flowering plants (i.e. floral cover) and the area of each garden dedicated to cucumber plants (i.e. cucumber cover). Although floral cover explained a greater proportion of the variance, cucumber cover had the strongest effect on conspecific pollen deposition. Heterospecific pollen deposition was positively and significantly related to garden area. However, no significant relationship was found between heterospecific pollen deposition and floral cover, or cucumber cover. Based upon these results, we hypothesize that floral cover positively impacts conspecific pollen deposition by attracting a greater number of pollinators into an urban garden, and that total cucumber area positively impacts conspecific pollen deposition when pollinators are locally foraging within a garden. We suggest that the arrangement of plants within a garden can positively influence yield in fruit and vegetable-producing plants within urban community gardens. Due to the low availability of fruits and vegetables within the stores of the neighborhoods where this study was conducted, developing a better understanding of those factors that constrain or foster fruit and vegetable production are important to increasing food security and public health. Keywords Pollination; pollen deposition; urban community gardens; cucumbers; acetolysis; New York City

A new method to evaluate the levels of residue and the dissipation of chlorothalonil fungicide in tomatoes and cucumbers grown in experimental greenhouses was developed and validated. The vegetables were submitted to a single spraying with chlorothalonil at half, equal to and double of the recommended dose. Chlorothalonil residues were extracted in Ultra-Turrax system using ethyl acetate in the presence of anhydrous sodium sulphate and determined by gas chromatography with electron capture detection. The analytical curves were linear from 0.005 to 5.0 mg L-1, with coefficient of determination higher then 0.995. The assays provide acceptable results with RSD values below 10.5% and recoveries were between 92.2 and 114.5% for tomatoes, and between 86.2 and 103.3% for cucumbers, both obtained from spiked samples at 0.028, 0.28, 2.8 and 5.0 mg kg-1 levels. Statistical interpretation of residue levels fitted to a first-order model for the dissipation behavior of chlorothalonil. The mean half-life after treatments at the recommended dose, in the two experimental years, was 8.8 days for tomatoes and 1.6 days for cucumbers. The higher decrease rate of chlorothalonil residues in cucumbers is mainly due to the higher growth rate of this vegetable relative to tomato. The developed method has proven to be efficient for the determination of chlorothalonil residues in tomatoes and cucumbers with a limit of quantification of 0.02 mg kg-1 level, permitting to evaluate the risk of consumer exposure to these residues. Desenvolveu-se e validou-se um novo método para avaliar os níveis de resíduo e a dissipação do fungicida clorotalonil em tomates e pepinos cultivados em estufas experimentais. Os vegetais foram submetidos a uma única pulverização com clorotalonil em meia dose, dose recomendada e dobro da dose. Os resíduos de clorotalonil foram extraídos em sistema Ultra-Turrax empregando acetato de etila na presença de sulfato de sódio anidro e determinados por cromatografia gasosa com detecção por captura de elétrons. As curvas analíticas foram lineares de 0,005 a 5,0 mg L-1, com coeficiente de determinação maior que 0,995. Os ensaios de precisão fornecem resultados aceitáveis com valores de RSD abaixo de 10,5% e recuperações entre 92,2 e 114,5% para tomate, e entre 86,2 e 103,3% para pepino, ambos obtidos para níveis de fortificação 0,028, 0,28, 2,8 e 5,0 mg kg-1. A interpretação estatística dos níveis de resíduo indicou um modelo de primeira ordem para o comportamento da dissipação do clorotalonil. O tempo médio de meia-vida para o tratamento na dose recomendada, nos dois anos experimentais, foram 8,8 dias para tomate e 1,6 dia para pepino. A taxa mais elevada da diminuição de resíduos de clorotalonil em pepino é devida, principalmente, à taxa de crescimento mais elevada deste vegetal com relação ao tomate. O método desenvolvido provou ser eficiente para a determinação de resíduos de clorotalonil em tomate e pepino até o nível de 0,02 mg kg-1, permitindo avaliar o risco da exposição do consumidor.

Institutional crises entail consequences in practically all areas of life, including the advertising. In this case, we highlight the response of the Spanish advertising brands, specifically Aguas de Mondariz, during the crisis of the cucumbers in the year 2011, which put into question the quality of Spanish products due to the accusations of the German authorities. Las crisis institucionales implican consecuencias en prácticamente todos los ámbitos de la vida, incluido el publicitario. En este caso, destacamos la respuesta de las marcas publicitarias españolas, concretamente Aguas de Mondariz, durante la crisis de los pepinos en el año 2011, que puso en entredicho la calidad de los productos españoles debido a las acusaciones de las autoridades alemanas.

While the distribution of herbivorous insects over leaves along the stem often shows a peak at some distance from the apex this does not necessarily reflect an innate preference as alternative explanations can be provided such as impact of predators and inter- or intraspecific competitors. It is of interest to determine which factors shape the distribution of insects over the leaves of a plant. Do leaves from different positions differ in suitability for insects and is that reflected in the insect's preference, or are other factors involved? In this paper we assess how the herbivorous insect western flower thrips, Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae), chooses among leaves from different positions relative to the apex of cucumber, Cucumis sativus (L.) plants. On leaf discs of a susceptible and three partially resistant cucumber accessions, thrips reproduction was highest on apical leaves and lowest on basal leaves. In dual-choice essays thrips females preferred younger leaves over older leaves for oviposition in all cucumber accessions tested, as was predicted from the no-choice assay. This indicates that differences in leaf suitability are an important factor in determining thrips distribution on cucumber plants.

There is a reason for the saying "cool as a cucumber." Cucumbers can be 20 degrees cooler on the inside than the outside temperature. It loves sunshine and is one of summer's favorite fruits (yes, it is a fruit because it has seeds. Interesting). Cucumbers are a member of the gourd family, which also includes pumpkins, zucchini, watermelon, and other squashes. Cucumbers are available year round, but honestly I wouldn't touch a cucumber until summertime, which is about August in Logan. If you think you don't like cucumbers, try a local one. It may change your mind. It certainly changed mine.

The official control of foodstuffs of the federal state of Brandenburg has found residues of the pesticide formetanate in a sample of cucumbers from Spain at a level of 0.13 mg/kg (maxi-mum residue level by law is 0.05 mg/kg). The Federal Institute for Risk Assessment has as-sessed whether the detected residue level is a health hazard for consumers. Based on various food consumption data, the Institute has estimated how much formetanate would be taken in by consumers through the consumption of cucumbers with this residue. The exposure assessment has shown that the acute reference dose (ARfD) for children is exceeded. The ARfD is defined as the amount of a substance in food which a consumer may ingest during one day (spread over one or several meals) without appreciable health risk. Yet, an exceedance of the acute reference dose on its own is not enough to conclude a health risk. In order to assess potential health risk, toxicologists rely on the margin of safety (MOS). The MOS indicates the margin between the NOAEL (no observed adverse effect level) obtained from animal experiments and the estimated amount of the substance taken in by consumers. In the case at hand, though the acute reference dose is exceeded, the margin of safety is wide enough so that the consumption of cucumbers with 0.13 mg/kg formetanate residues is unlikely to be a health hazard – even for children. The estimation of the degree to which the acute reference dose is reached reveals whether a health hazard is possible. Yet even if the exhaustion of the complete reference dose does not constitute a health hazard, the product has to be removed from the market if maximum residue levels of pesticides have been exceeded.

An epidemiological study carried out by the Robert Koch Institute (RKI) together with the Hamburg health authorities shows that patients affected by the current EHEC outbreak con-sumed significantly more frequently raw tomatoes, cucumbers and green salads than healthy study participants. It has not yet been established whether one or more of these three foods are linked to the outbreak events. Against this backdrop RKI and BfR recommend, by way of precaution, not to consume raw tomatoes, cucumbers and green salads, more particularly in Northern Germany, until further notice.

Chemical and sensorial changes related to the use of benzoates and ascorbic acid as additives in packed fermented vegetables were investigated. For this, three selected vegetables (green olives, cucumbers, and caperberries) stored under different conditions (glass or plastic containers, ambient or refrigerated storage) were used. In all cases, benzoic acid remained unchanged (glass bottle) or decreased slightly (plastic pouch) at prolonged storage. Ascorbic acid was partially or totally degraded during storage, the degradation rate depending on the storage conditions and the vegetable matrix. Benzene levels higher than 10 μg/L were found in cucumbers and caperberries containing both additives, but only when packed in plastic pouches and after prolonged storage at room temperature. In these conditions, an appreciable browning of brine, related to AA degradation, was also found. The use of benzoate alone had a significant influence on vegetable color, but flavor was not significantly affected at the benzoate levels tested. On the basis of the present study, benzoates should be removed from fermented vegetable formulations containing ascorbic acid to eliminate possible benzene formation during long-term storage. © 2011 American Chemical Society.

Cucumber mosaic virus strain K8 (K8-CMV), originally isolated in NW Italy from Cucumis metuliferus, was sent to us by Dr. Lisa after being passaged and multiplied in tobacco. Northern blots to probes against Fny-CMV (subgroup I) and Ls-CMV (subgroup II) showed K8-CMV to belong to subgroup I of CMV isolates (1). In agarose gel electrophoresis of virion encapsidated RNAs a fifth RNA was found, shown to be a satellite RNA (K8-sat RNA)., This work was supported by grant PA8 6-0353, CICYT, Spain.

Dry matter distribution is an important factor determining the crop yield. A preliminary model for dry matter distribution in crops with indeterminate growth like cucumber and tomato is described and some results are shown. The simulated dry matter distribution is primarily regulated by the sink strengths of the individual (clusters of) fruits. The sink strengths of individual (clusters of) fruits can be quantified by their potential growth rates, i.e. the growth rates under conditions of non-limiting assimilate supply. The simulated dry matter distribution among individual clusters of tomato fruits corresponded reasonably well to measured data.

Cultuurfiltraten van 17 mycoparasitaire schimmelsoorten, die waren geisoleerd van andere schimmels, werden getoetst op hun werkzaamheid tegen komkommermeeldauw, Spaerotheca fuliginea. De beste biologische bestrijding werd verkregen met Calcarisporium arbuscula