A survey of weed seed production in vegetable crops of Setifian high plateau

Abstract

Weeds are one of the most significant limiting factors in agricultural production. Weeds compete strongly with crops for light, water and nutrients. This brings about severe interference with normal crop growth, causing high crop losses and reducing the quality of produce. Most annual weeds produce a prolific number of seeds each year. Production of abundant small seeds is a common adaptation that ensures a high probability of dispersal and re-infestation. With this background, the experiment was to counting the number of seeds produced by plant weed presented in legumes and garlic crops of Setifian high plateau. Seed production of 68 weed species (56 broadleaves, 12 annual grasses and one LiIiaceae) collected from 38 vegetable crops was investigated in the north east of Algeria (the Setifian high Plateau). Weed plants were harvested in may 2014 at maturity of legumes and garlic crops, and the number of seeds per plant was determined. four weeds produced more than 1500 seeds/plant and four produced between 1000 and 1500 seeds/plant, 17 weeds had between 500 and 1000 seeds/plant, 30 weeds had between 100 and 500 seeds/plant and 13 had less than 100 seeds/plant in at least one of the two vegetable crops. The eight high seed producing weeds (more than 1000 in at least one vegetable crop) were Sinapis arvensis, Sonchus asper, Papaver hybridum, Bromus lanceolatus, Capsella-bursa-pastoris, Glaucium corniculatum, Papaver rhoeas, Bromus madritensis. Of the 30 species that produced between 100 and 500 seeds / plant, seven species are Asteraceae, five Fabacea, five Apiaceae and three are poaceae. Nine species have produced almost the same number of seeds in both legumes than garlic crops are: Lathyrus ochrus, Vicia monantha,Vicia sativa, Convolvulus arvensis, Melilotus indicus, Vicia hirsuta Sonchus oleraceous, Hordeum murinum, Chrysantemum segetum. Any longterm strategy for weed management should focus on mininizing weed seed production.