Caracterisation De La Flore Adventice Des Cultures Maraicheres De La Region De Jijel (algerie)

Weed flora of annual crops in Jijel were caracterized in three successive growing seasons by measuring species frequencies and abundance over 65 fields. A total of 191 species in 111 genera were recorded representing a total of 44 families with Asteraceae, Fabaceae, Poaceae, Brassicaceae, Geraniaceae and Polygonaceae predominating. Only 4 species (namely Polygonum aviculare L., Chenopodium album L., Cyperus esculentus L., Amaranthus retroflexus L. and Convolvulus arvensis L., occurred in more than 50% of the plots. The plots where the density exceeded 20 plants per m2 were observed for Cyperus esculentus. The total number of weed species per plots varied from 4 to 65 with a median species number of 20. In most of the plots, the weed community was mainly composed of species having a small density (less than one plant per m2) and was dominated by only one or two species in half of the plots.