How to Manage Pests
UC Pest Management Guidelines
In the field, lower leaf yellowing and often stunting of garbanzo bean plants are the earliest symptoms. Subsequently the plant wilts and dies. When root knot nematodes are present, symptoms are usually more severe. When the root or stem of the plant is cut tangentially with a sharp knife, the woody (xylem) tissue is dark brown. This pathogen does not ordinarily cause a root rot; however, root rots caused by other pathogens such as Pythium spp., Fusarium solani, Thielaviopsis basicola, and Macrophomina phaseolina may be associated with the disease.
Fusarium oxysporum survives in soil for several years as chlamydospores and is specific to garbanzos. The fungus is systemic and once the plant is infected, it cannot be cured.
Care should be taken to differentiate Fusarium wilt from a yellows disease caused by one or more viruses that are transmitted by aphids. The viruses will cause yellowing of the plant but the color is brighter than with Fusarium wilt. If a virus disease is suspected, the main symptom to look for is a dark brown color of the bark tissue (phloem or sugar conducting tissue) when cut open with a sharp knife.
Long-term crop rotation (over 5 years) may help to reduce inoculum in soil. In fields with a history of Fusarium wilt, resistant cultivars should be planted. UC-15, adapted to coastal areas, and UC-27, adapted to the Central Valley, are resistant.
UC IPM Pest Management Guidelines: Dry