Effects of organic and inorganic mulching, nettle extract, and manual weeding on weed management under direct-seeded lentil in Meknes region, Morocco

Weeds represent a major problem for the production of food legumes in Morocco. In order to cover its legume needs, the country currently imports this commodity, particularly lentils (Lens culinaris Medik.). The present study was conducted to investigate the effects of some agroecological strategies, such as manual weeding, fermented nettle extract (Urtica dioica L.), black plastic, and wheat straw mulching, on weed management, yield and yield components of lentil. The experiment was carried out at the Agroecology and Environment platform of the National School of Agriculture in Meknes, Morocco, in 2020–21 and 2021–22. Five treatments were tested in a complete randomized block design with four replications. The data analysis revealed that crop competition with weeds can result in a yield loss of over 60%. The weed flora identified was very diverse, with 27 different species. All treatments resulted in effective weed management compared to the control (untreated), significant economic gains and a difference in protein content, and a significant decrease in weed density and dry biomass by more than 50% at the flowering and maturity stages. The nettle extract treatment was less effective than the other treatments, but did not show phytotoxic effects on the crop, and it inhibited the germination of more than 50% of Glebionis coronaria (L.) seeds and more than 80% of Avena stirilis (L.) seeds compared to the control under laboratory conditions, which was confirmed in the field. The agroecological practices tested in this study resulted in the highest yield and yield components of the lentil crop compared to the control, leading us to conclude that reducing weed infestation is useful in cropping systems where chemical or mechanical weed control is not feasible, and for crops with low weed competitive ability.