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Renommée depuis la plus haute antiquité pour son ancienneté et son excellence, la médecine égyptienne a-t-elle pu influencer la médecine occidentale et, si tel est le cas, en quoi et de quelle manière ? Que s’est-il passé lorsque la médecine grecque héritée d'Hippocrate a été importée en Égypte à la suite de la conquête du pays par Alexandre le Grand, en 332 avant notre ère ? Après avoir comparé les écrits médicaux égyptiens et grecs et les pratiques médicales attestées dans le Pays du Nil et dans le monde hellénique, on examinera, à côté des sources littéraires qui font de l' « école médicale d'Alexandrie » un modèle qui restera pour longtemps inégalé, les papyrus médicaux grecs (des IVe/IIIe siècles avant notre ère au VIIe siècle de notre ère), retrouvés en nombre sans cesse croissant dans les sables égyptiens, ainsi que d'autres sources archéologiques, en vue de répondre à ces questions.

Wheat yellow dwarf disease is caused by barley yellow dwarf virus (BYDV), which is transmitted by wheat aphid and causing huge loss in agriculture. Nowadays, induced resistance has aroused great discussion as a new measure to control plant pathogens and herbivores. Protein elicitor Hrip1 induced defense response in various plants, leading to broad spectrum resistance. In this study, we evaluated the control efficiency of Hrip1 against BYDV. Wheat seeds and seedlings were soaked and sprayed with 30 μg/mL Hrip1, respectively, and then inoculated with BYDV. The control efficiency of Hrip1 against BYDV was over 50% at 14th dayafter BYDV inoculation and over 30% at 21th dayafter BYDV inoculation. Q-RT- PCR test showed that quantity of mRNA for BYDV coat protein was less in Hrip1 treated wheat seedlings than that of control. EPG test showed that Schizaphis graminum performed longer time to find probe site on leaf surface and feeding site in phloem on Hrip1 treated wheat seedings. These results suggested that Hrip1 is efficient in inhibiting BYDV proliferation, and affecting feeding behavior of S. graminum, futher more reducing virus transmission ability of S. graminum. Additionally, Hrip1 weakened the symptom of dwarf and yellow in wheat seedlings caused by BYDV. In conclusion, Hrip1 could be a biological agent to integrately control BYDV. National Key R&D Program of China; Chinese Academy of Agricultural Sciences

Comment et pourquoi enseigne-t-on la théorie de l'évolution en Europe et plus particulièrement en Belgique francophone? Quels sont les enjeux et les moyens?

Protein elicitor Hrip1 was found to effectively control wheat aphid by decrease the aphid population

Abstract: The concept of pest control has been changed from traditional “kill” to scientific “regulation”. Ecological regulation has become one of the hotspots in the field of sustainable agriculture. Intercropping (i.e., the simultaneous growing of two or more species in the same field for a significant period but without necessarily being sown and harvested at the same time), is one way to increase the plant diversity. In addition to intercropping, semiochemicals (i.e., informative molecules used in insect-insect or plant-insect interactions) have been widely considered within various Integrated Pest Management (IPM) strategies. Laboratory and field studies have demonstrated that releasing semiochemicals has the potential to simultaneously repel pests and attract natural enemies. For instance, methyl salicylate (MeSA) is a herbivore-induced plant volatile that is repellent to Rhopalosiphum padi (L.) and other cereal aphids, while being attractive to aphid predators such as ladybeetles, lacewings and hoverflies, and increasing parasitism rate. Moreover, the aphid alarm pheromone, which major component is E-β-farnesene (EBF), acts as a repellent for plant herbivores, and attracts predatory beetles, hoverflies and increase parasitism rate. Combining both strategies could be an interesting way to maximize pest control. In a 2 year set-up (March-August 2015, 2016), a wheat-pea strip intercropping combined with the release of EBF or MeSA was tested in Gembloux to improve push-pull strategy by repelling aphids and by attracting beneficials simultaneously. The results showed that the abundance of aphids, lacewings and mummified aphids on both pea plants and wheat tillers were all affected by the release of oil formulated EBF and MeSA. Parasitism rate was also affected by the treatments on both crops in both years. The occurrence of wheat aphids and pea aphids were reduced by 35% and 30%. In the case of wheat and pea, pea aphids peak earlier than wheat ones (in the present study on plants, pea aphids: 17 June 2015 and 3 June 2016, while wheat aphids: 25 June 2015 and 10 June 2016), hence associating these two crops allows natural enemies to quickly move from pea to wheat and controlling pests in the course of their occurrence, in fine protecting both crops. Wheat–pea intercropping combined with EBF oil and MeSA release, enhanced the abundance of predators and parasitoids on the pea, our results strongly support the efficacy of combining intercropping and semiochemical release to attain improved pest control. Key words: Ecological regulation; Methyl salicylate; Aphid alarm pheromone; Push-pull; Green control 中比国际科技合作项目（2014DFG32270）