Dodder (Cuscuta spp.) is a parasitic plant that poses a major threat to agricultural and forestry systems by attaching to host plants, extracting nutrients, and impairing growth. In Africa, indigenous trees that are critical for ecosystem services, soil conservation, and local livelihoods are increasingly impacted, yet the molecular mechanisms underlying their innate resistance to dodder remain poorly understood. Current management strategies are largely reactive, with limited emphasis on leveraging natural resistance traits, chemical defenses, or host-induced molecular responses to limit parasitism.
Gaps:
- Limited Understanding of Resistance Mechanisms: There is insufficient knowledge of the molecular, biochemical, and genetic bases of dodder resistance in indigenous trees.
- Lack of Resistant Germplasm Screening: Indigenous tree populations have not been systematically screened to identify resistant individuals suitable for conservation or breeding programs.
- Unexplored Molecular and Chemical Defense Pathways: The roles of secondary metabolites, defensive proteins, hypersensitive responses, and host-induced gene silencing (HIGS) in resisting dodder remain largely uncharacterized.
- Absence of Translational Strategies: Few approaches integrate molecular insights with practical interventions to enhance dodder resistance in trees or guide ecosystem management.
CWISA’s Approach:
CWISA seeks to fill these gaps by combining ecological, molecular, and biochemical approaches to understand and exploit dodder resistance in indigenous trees. Our strategy involves:
- Screening diverse indigenous tree species for natural resistance to dodder.
- Selecting resistant individuals for detailed molecular and chemical analyses.
- Identifying dodder-derived signals that trigger host defense genes.
- Characterizing potential chemical defenses (e.g., toxic secondary metabolites, defensive proteins) and RNA-based defense mechanisms, including host-induced gene silencing.
This integrated approach will generate knowledge to support the conservation of resistant tree populations and the development of innovative, science-based strategies to mitigate dodder infestation.
Objectives:
- Screen and identify indigenous tree species exhibiting innate resistance to dodder across selected regions.
- Characterize the molecular and biochemical mechanisms underlying resistance, including defensive metabolites, proteins, and hypersensitive responses.
- Investigate dodder-host signaling pathways that activate defense genes in resistant trees.
- Explore RNA-based strategies, such as host-induced gene silencing, to enhance or transfer resistance traits for sustainable tree protection.
Contact: info@cwisa.org