[Onions: Pests and diseases]

agentes nocivos agua allium cepa biological development botrytis allii cebolla chemical control clima climat climate crecimiento croissance eau enfermedades de las plantas enfermedades fungosas environmental factors facteur du milieu facteur nuisible factores ambientales fungal diseases growth infection injurious factors lutte chimique maladie des plantes maladie fongique oignon onions peronospora peronospora destructor plant diseases population symptome symptoms thrips tabaci water