0000000000670882
AUTHOR
Jean-philippe Guillemin
Identification et caractérisation de candidats d’origine naturelle à action herbicide pour contrôler les adventices
EASPEIPMGESTADAGROSUPINRA; The use of herbicides to control weeds is very common. However, some herbicides are both environmentally detrimental and human unhealthy. The use of microorganisms acting as natural herbicide could be an alternative control method. Symptomatic weeds will be collected in field. Microorganisms will be isolated from symptomatic weeds, purified, identified and inoculated on weeds to confirm Koch’s postulates. The identified pathogenic microorganisms will be tested against a selection of weeds and crops to characterize the host range and the specificity of these microorganisms. In parallel, the diversity of endophytic microorganisms of symptomatic weeds will be charact…
Capacité des adventices à germer en surface dans diverses conditions
EASPEGESTADINRAAGROSUP; Les espèces annuelles produisent des graines chaque année pour maintenir leur population. Ces graines tombent à la surface du sol. Si aucun travail du sol n’est réalisé (ex. cas du semis direct), les graines doivent germer en surface du sol, exposées aux variations environnementales, et parfois même dans un couvert. Cette étude a permis d’étudier l’effet du non-enfouissement des graines, et des conditions environnementales (humidité, lumière, présence d’un couvert) sur la germination, l’émergence et la croissance de nombreuses espèces annuelles. La germination est réduite (en moyenne, toutes espèces confondues) de 26% lorsque les graines sont laissées en surface, de …
Approches de la nuisibilité du bleuet en colza d'hiver
Infestation of oilseed rape fields by cornflower is more and more frequent, which could become harmful. In contrast, cornflower produces nectar that is a resource for pollinators and probably crop pest predators and parasitoides. In order to get benefit of this resource, it is necessary to determine a balanced equilibrium between the services and the weediness of cornflower in spite of destroying it. We describe here bispecific competition trials against oilseed rape in small experimental plots. Experimental conditions led to too high or too small plant densities to estimate a threshold of competition. Results provide relevant information on self-concurrence among cornflower plants and on i…
Quelles pratiques agricoles pour préserver les peuplements riches en espèces messicoles ?
A consequence of the agricultureal intensification of the second part of the XXth century is the depletion of some species linked to arable fields. These species called “segetal” are considered since 2012 under a National Action Plant (PNA). A survey has been conducted to explore the relationships between these segetal weeds and agricultural practices. It involved 159 farm plots for two years in three regions having contrasted climates, soils and farming systems. Data of species richness are presented in relation to agricultural practices. They cannot allow hierarchical ranking of the most favourable practices, whatever the region, but rather the presence of segetal weeds is associated with…