Genetic diversity among North African faba bean landraces for competitive ability against weeds

The genetic diversity of Moroccan faba bean (Vicia faba L.) landraces should be exploited to improve the competitive ability of faba beans against weeds. The objective of this study was to in-detail evaluate competitive ability and productivity of a collection of Moroccan faba bean landraces relative to a model weed, Sinapis alba. Sixty Moroccan faba bean landraces and two checks were evaluated in 2011 and 2013 for grain yield and further agronomic traits, with and without model weed stress, under field conditions at two locations in the northwest of Morocco, using a split-plot design. The landraces showed significant genetic variation for productivity and competitive ability. Several landraces exhibited higher values compared to the two checks. Yield loss attributable to weed stress was, on average, about 69%; the weed competitive index was, on average, about 1.28. Landraces × weed treatment interaction for yield was a highly significant and marked source of variation. Several landraces were found to combine high levels of both, competitive ability against the model weed and productivity.