The effects of phosphite treatment against phytophthora root rot disease on Leucadendron argenteum.

This study evaluated the effectiveness of phosphite, a systemic fungicide, as a management tool against Phytophthora cinnamomi in South African ecosystems. It also assessed the health status of existing Leucadendron argenteum populations and identified variations in susceptibility to P. cinnamomi. The study utilised field surveys, controlled inoculation experiments, and field trials to assess phosphite effectiveness. Population dynamics and disease susceptibility varied significantly among L. argenteum populations. The Rhodes Memorial site demonstrated high resistance to P. cinnamomi, indicating potential genetic bases for resistance. Phosphite has been shown to reduce disease symptoms in seedlings through controlled inoculation experiments, but these results may not be applicable to mature trees in the field.