Phytophthora dieback in banksias: Screening for resistance

Abstract

Screening methods were investigated for assessing the resistance/susceptibility of Banksia species to Phytophthora infection. P. cinnamomi Rands was isolated most frequently from soil under infected Banksia plants in South Australia. Two isolates of P. citricola Sawada were also identified. Preliminary results indicated the response of excised shoot material to be quite variable and dependent on seasonal variations. The excised root assay showed potential as a routine screening assay. Micropropagation of B. coccinea has been successful and material will be included in an in vitro inoculation assay. Research continues into the handling of in vitro propagated plantlets.