Contribution à l'étude de la biologie de Solanum elaeagnifolium Cav. (Solanacées), adventice des cultures dans le périmètre irrigué du Tadla (Maroc)

A contribution to the study of the biology of Solanum elaeagnifoloium Cav. (Solanaceae), a weed of crops in the irrigated perimeter of the Tadla (Morocco) Solanum elaeagnifolium Cav. currently infests 100 000 ha of irrigated crops in the Tadla perimeter (Central Morocco). Its remarkable capacity for vegetative reproduction is associated on the one hand with the intensity of the tillage and on the other with its biological type as a geophyte. Moreover it is equally capable of sexual reproduction. It produces large numbers of seeds which germinate from February onwards, just as the vegetative shoots appear, a fact which increases its aggressiveness. In Morocco, the species flowers in May and starts fruiting in July while in winter it is vegetatively dormant. Consequently, it presents a threat in general and in particular to spring crops (cotton, maize, sesame, etc.).