Identification of the causes of onion (Allium cepa) post-harvest losses in Morocco

L’oignon figure parmi les principales cultures maraîchères au Maroc. Cependant, plusieurs types de pertes peuvent avoir lieu après leur récolte. Notre objectif est d’étudier la situation de cette filière en post récolte et d’identifier les causes et les contraintes rencontrées au cours de la mise en vente et de la consommation de ce produit dans la région de Khémisset (Maroc). L’enquête auprès de certains acteurs de cette filière nous a permis de déterminer les types et l’ampleur des pertes. Les dégâts observés sont causés principalement par des facteurs mécaniques et pathologiques. Nous avons identifié deux champignons phytopathogènes, Fusarium sp. et Aspergilus niger. En outre, l’étude a révélé des pertes moyennes d’environ 17% chez les grossistes, 15 % chez les commerçants et 27% chez les ménages. Mots-clés: Pertes en post-récolte, oignon, champignons phytopathogènesOnion is one of the main commodities in Morocco. However, several types of losses may occur at postharvest. Our objective is to study the situation of this post-harvest sector and to identify the causes and constraints encountered during the sale and consumption of this product in Khémisset region (Morocco). The survey of certain stakeholders allowed us to determine the types and extent of losses. The damage observed is caused mainly by mechanical and pathological factors. We identified two phytopathogenic fungi, Fusarium sp. and Aspergilus niger. In addition, we found that average losses were of about 17% among wholesalers, 15% among traders and 27% among households. Keywords: Postharvest losses, onion, phytopathogenic fung

PLATEFORME MULTISERVICE INNOVANTE MEDECIN/PATIENT A BASE DE RESEAU DE CAPTEURS

Dans les hôpitaux, chaque patient voit ses constantes physiologiques surveillées en permanence, jour et nuit, par une infirmière. Par conséquent, il est préférable d’avoir des outils et des appareils sans fil pour la prise des données vitales sur une personne hospitalisée, permettant une diminution des erreurs et des oublis de notification dans le dossier médical. Il est avéré que la guérison la plus rapide a lieu au domicile même du patient ; c'est pourquoi les médecins souhaitent le développement de capteurs ou moniteurs à technologies sans fil pour suivre l'évolution d'une thérapie ou d'un traitement à distance. Celle-ci deviendra donc propre à chaque personne et adaptable selon les besoins. Chaque citoyen devient de plus en plus acteur de sa santé. Par exemple, un patient peut consulter le nom et le dosage d’un médicament spécifique à prendre en suivant les conseils et les messages des médecins figurant sur son compte depuis son ordinateur personnel. Grâce aux capteurs, la société peut permettre aux malades cardiaques de mener une vie indépendante et à domicile tant qu'elles en sont capables. Ce papier présente notre réflexion sur la mise en place d’un système à base des réseaux de capteurs dans le domaine de télémédecine, et spécialement le suivi de l’état des malades cardiaques à domicile

In vitro mycorrhization of Argania spinosa L. using germinated seeds

The beneficial effects of arbuscular mycorrhizal fungi (AMF) on the growth and nutrition of argan plants have been reported in several studies conducted under greenhouse or field conditions. However, none of these studies considered the in vitro mycorrhization of those plants, despite the benefits of this technology on the enhanced survival and fast recovery at transfer to hardening conditions reported in several plants of economic importance (e.g. banana and hevea). In our study, we succeeded for the first time the association of argan plants with an AMF (Rhizophagus irregularis MUCL 41833) under in vitro culture conditions and their successful transfer from in vitro to greenhouse conditions. We tested three argan accessions, Tidzi (TD), Mejji (MJ) and City Hanchan (CH), and grew surface-sterilized seeds in the mycelium donor plant in vitro culture system. Whatever the accession, root colonization, with the presence of arbuscules, vesicles/spores and hyphae, was observed after 8 weeks of growth in the extraradical mycelium network of the fungus, and reached values between circa 30 and 50% of total root colonization after 11 weeks, with significant differences between the accessions. Plants survived transfer from in vitro to greenhouse conditions (peat-sand mixture substrate), and roots remained highly colonized after five months. Whatever the accession, a significant increase was noticed in the growth of AMF-colonized plants. Differences were also observed between accessions, with TD showing the highest relative mycorrhizal dependency and CH the lowest. The relative mycorrhizal dependency was correlated with the % of total colonization, % of arbuscules colonization and % of hyphae colonization within roots. The concentration of chlorophyll a and b was also increased in the leaves of the AMF-colonized plants, whatever the accession. In conclusion, the in vitro association of argan seedlings with R. irregularis MUCL 41833 allowed good root colonization and improved the growth of the plants after transfer to the greenhouse. This technology thus represents a promising approach for the production of biotized argan plants with faster recovery and growth at transfer to the greenhouse and possibly to the field

Effectiveness of Postharvest Treatment with Chitosan to Control Citrus Green Mold

Control of green mold, caused by Penicillium digitatum, by fungicides raises several problems, such as emergence of resistant pathogens, as well as concerns about the environment and consumers’ health. As potential alternatives, the effects of chitosan on green mold disease and the quality attributes of citrus fruits were investigated. Fruits were wounded then treated with different concentrations of chitosan 24 h before their inoculation with P. digitatum. The results of in vitro experiment demonstrated that the antifungal activity against P. digitatum was improved in concert to the increase of chitosan concentration. In an in vivo study, green mold was significantly reduced by chitosan treatments. In parallel, chitinase and glucanase activities were enhanced in coated fruits. Evidence suggested that effects of chitosan coating on green mold of mandarin fruits might be related to its fungitoxic properties against the pathogen and/or the elicitation of biochemical defense responses in coated fruits. Further, quality attributes including fruit firmness, surface color, juice content, and total soluble solids, were not affected by chitosan during storage. Moreover, the loss of weight was even less pronounced in chitosan-coated fruit