Decline of Pratylenchus coffeae and Radopholus arabocoffeae populations after death and removal of 5-year-old arabica coffee (Coffea arabica cv. Catimor) trees

Abstract

AbstractThe decline of populations of the plant-parasitic nematodes Radopholus arabocoffeae and Pratylenchus coffeae was studied after the death and removal of severely damaged coffee plants (Coffea arabica cv. Catimor) in a field naturally infested with both nematodes. Soil samples were taken at monthly intervals up to a depth of 70 cm and divided into 10 cm segments from which nematodes were extracted. The numbers of R. arabocoffeae and P. coffeae in soil and in root fragments were determined. Both species were found up to 70 cm depth. Densities of R. arabocoffeae and P. coffeae populations declined exponentially over time in all soil layers. No nematodes were found in soil and root fragments 10 and 11 months after removal of the infected coffee plants for R. arabocoffeae and P. coffeae, respectively. Arabica coffee seedlings were planted in soil collected from the experimental plots after these time periods. The seedlings were grown for 3 months in a glasshouse and then roots and soil were analysed for presence of both nematode species. No R. arabocoffeae and P. coffeae were found, confirming that the population in the field had completely declined. The results of this experiment demonstrate that a replant of coffee is possible 1 year after removal of infected plants from a plantation without any further (chemical) control measures.