Biological Control of Dodder (Cuscuta Sp ) In Alfalfa Plant (Medicago sativa.L ).

Abstract

Dodder( Cuscutasp) grass is a unique group of parasitic dicotyledons that can infect nearly all dicotyledon species. The damage caused by this weed to the alfalfa crop (the world's most important forage crop) mainly includes a low level of fresh biomass and a significant reduction in seed production. Effective field bearer control is a necessity. It includes a number of preventive measures and measures in addition to the biological control program which is a more effective alternative technique. This research was conducted at Sudan University of Science and Technology, College of Agricultural Studies, after a survey of Xanthium strumarium weeds that are attacked by dodder weedto find out the organisms associated with these weeds after noticing some pathological spots on them to arrive at a biological control of dodder weed. The pathogen was isolated from Xanthium strumarium weed was found to be Curvularia lunata. This fungus Curvularia was used in addition to Trichderma fungus and Bacillus subtilis bacteria and mesquite plant extract in three concentrations (25, 50, and 75,%) in control of dodder. The results of this study showed that the Trichderma powder was effective in reducing or inhibiting the growth of the dodder and gave highest growth of alfalfa plants compared to the untreated plants. The percentage of control for the Trichdermawas (95%), followed by B.subtilis bacteria (83.33%), Mesquite 75% (70%), the fungus Curvularia (46.66%), Mesquite 50% (46.66%) and Mesquite 25% was scored (26.66%).