The role of nodulation and damping-off in lucerne establishment on acidic sandy soils on the Darling Downs

Abstract

Four experiments on two soils with deep acid sand A horizons on the western Darling Downs in 1968 and 1969 investigated poor establishment of lucerne. Rates of rhizobial inoculation, lime pelleting, lime banded with the seed, and incorporation of fungicides in the lime pellet or applied to the soil, were examined. The main factor in poor establishment was seedling losses from damping off caused by Pythium irregular.. Establishment increased when the fungicide Dexon was incorporated in the lime pellet, and Dexon had no adverse effects on nodulation. To obtain full nodulation the use of higher than minimum standard quality inocula and lime pelleting were required. On the more acidic soil (pH 5.0, 0-10 cm) additional lime banded at 250 kg ha-1 was beneficial.