Pathogenicity of migratory endoparasitic nematodes on coffee seedlings ( Coffea arabica cv. K7) in Australia

Plant-parasitic nematodes cause significant losses to coffee globally, but to date, there have been no reports of nematodes causing adverse effects to coffee crops in Australia. Four species of migratory endoparasitic nematodes, including Pratylenchus coffeae, Pratylenchus brachyurus, Pratylenchus zeae, and Radopholus similis , were detected in coffee-growing areas of Australia and their molecular data were also deposited in GenBank under accession numbers MN796428, MN718729, MN831891, and MN796426 respectively. A pathogenicity test of these nematode species was performed on seedlings of Coffea arabica cv. K7 under glasshouse conditions. We found that seedlings inoculated with P. coffeae and R. similis (both isolated from banana roots) and P. brachyurus (isolated from coffee roots), were stunted and their root systems were severely damaged. Tap roots and lateral roots of Coffea arabica cv. K7 were destroyed by P. coffeae , whereas P. brachyurus , and R. similis mainly damaged tap roots. Pratylenchus zeae , originally isolated from Saccharum spp., was not pathogenic to Coffea arabica cv. K7. This is the first report of nematode species capable of damaging coffee in Australia and the results demonstrate that nematodes pose a potential threat to coffee production.