Aureobasidium pullulans strain Ach1-1 was selected for its effectiveness against blue mold caused by Penicillium expansum on stored apple fruit. The possible involvement of competition for nutrients in the biocontrol activity of this antagonistic strain was investigated both in vitro and in situ. For in vitro assays, the effect of strain Ach1-1 on germination percentages of P. expansum conidia was evaluated after a 24 h incubation period in the presence of increasing apple juice concentrations (0-5%) using a system allowing the physical separation of both agents. In the absence of strain Ach1-1, conidial germination was strongly promoted by apple juice whatever the concentration. However, germination was significantly reduced by the presence of strain Ach1-1 except at the highest juice concentration. For conidia previously inhibited at 0.5% juice, germination after 24 h of incubation was partially recovered in the presence of strain Ach1-1 when fresh juice was added to a final concentration of 5%, and completely restored at both 0.5 and 5% juice concentrations in the absence of strain Ach1-1. For in situ assays, strain Ach1-1 was very protective against P. expansum on postharvest wounded apples. However, the application of high concentrations of exogenous sugars, vitamins and most particularly amino acids, significantly reduced such protection. Time-course analysis of apple amino acids at the wound site revealed that these compounds were more depleted in wounds treated with strain Ach1-1 alone and especially in those treated with both agents (strain Ach1-1 and P. expansum) compared to wounds treated with P. expansum alone or to untreated ones. Exogenous amino acids, applied at high concentrations on apple wounds as a mixture of specific amino acid groups or as individuals, significantly decreased strain Ach1-1 efficacy against P. expansum. The present study provides in vitro and in situ evidence that competition for apple nutrients, most particularly amino acids, may be a main mechanism of the biocontrol activity of A. pullulans strain Ach1-1 against blue mold caused by P. expansum on harvested apple fruit.

-Photosynthetic activity of cereals has traditionally been studied using leaves, thus neglecting the role of other organs such as ears. Here, we studied the effects of water status and genotypes on the photosynthetic activity of the flag leaf blade and the ear of durum wheat. The various parameters related to the photosynthetic activity were analysed in relation to the total above-ground plant biomass and grain yield at maturity. Four local varieties plus two cultivars adapted to the semiarid areas of South Morocco were grown in pots in a greenhouse. Five different water treatments were maintained from the beginning of stem elongation to maturity, when shoot biomass and grain yield were recorded. The net photosynthesis (A), stomatal conductance (g s ) and transpiration (T) of the ear and the flag leaf were measured at anthesis. In both organs these factors decreased significantly with water deficit, whereas the A/T and A/g s ratios increased. The genotype effect was also significant for all traits studied. Whole-organ photosynthesis was much higher in the ear than in the flag leaf in well-watered conditions. As water stress developed, photosynthesis decreased less in the ear than in the flag leaf. Whole-ear photosynthesis correlated better than flag leaf photosynthesis with biomass and yield. Nevertheless, the relationships of the whole flag leaf with biomass and yield improved as the water stress became more severe, suggesting a progressive shift of yield from sink to source limitation. For all water regimes the ratios A/g s and A/T of the ear also showed a higher (negative) correlation with both biomass and yield than those of the flag leaf. The results indicate that the ear has a greater photosynthetic role than the flag leaf in determining grain yield, not only in drought but also in the absence of stress. durum wheat / ear / flag leaf / photosynthesis / yield / drought Résumé -Comparaison des relations entre photosynthèse de la feuille étendard et de l'épi avec la biomasse et le rendement en grain chez le blé dur sous différents régimes hydriques. Traditionnellement, lorsque l'activité de la photosynthèse de céréales est étudiée, l'importance est attribuée aux feuilles, négligeant ainsi le rôle d'autres organes comme l'épi. Ici, une étude comparative de l'effet du statut hydrique sur l'activité photosynthétique au niveau de la feuille étendard et de l'épi ainsi que leurs relations avec la biomasse totale aérienne et le rendement en grain à maturité a été menée chez le blé dur. Quatre variétés locales et 2 cultivars adaptés aux zones semi-arides du sud du Maroc ont été mis en croissance dans des pots en conditions de serre. Cinq différents régimes hydriques ont été instaurés du début de l'élongation des tiges jusqu'à maturité. La biomasse et le rendement en grain sont alors enregistrés. Des mesures de la photosynthèse nette (A), de la conductance stomatique (g s ) et de la transpiration (T) ont été effectuées au niveau de l'épi et de la feuille à l'anthèse. Pour les deux organes, on note une diminut...

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To identify factors that influenced Moroccans’ intention to get a COVID-19 vaccine, a cross-sectional survey among a Moroccan sample was conducted based on Health Belief Model constructs. Participants’ sociodemographic characteristics, perceived susceptibility, perceived severity, perceived barriers, perceived benefits, self-efficacy, cues to action, and intention to receive vaccine data were collected and analyzed using a structural equation model (SEM). The survey was completed by 3800 individuals; 57.2% were men, 44.5% were aged 30 to 44, and 44.6% were married. After controlling for confounders, being a woman and having a chronic disease were associated with higher acceptance of the COVID-19 vaccine. The strongest predictor for the intention of receiving a vaccine was participants who were married. Most of the HBM constructs were shown to be significantly associated with vaccine acceptance. Susceptibility and Benefits were the strongest predictors of acceptance of the COVID-19 vaccine (standardized path coefficient, SPC = 0.23), followed by Severity (SPC = 0.22). Conversely, given the negative correlation between barriers and intention (SPC = −0.08), it is necessary to maintain a high level of transparency regarding the vaccines’ safety. Our study provides guidance for an implementation of vaccination strategies, intending to bolster the overall COVID-19 immunization program.

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