Cereal cyst nematode (Heterodera avenae) in Victoria: influence of cultural practices on grain yields and nematode populations

Abstract

The effect of several agronomic strategies on grain yields and cereal cyst nematode (Heterodera avenae) populations were studied at Sea Lake in the Victorian Mallee between 1967 and 1972 on a soil known to be heavily infested with the nematode. The resowing of damaged crops with either wheat or barley was not effective in producing higher yields, although cyst populations were lower on the resown crops-especially barley. Nitrogen fertilizers (urea and sulphate of ammonia) both produced small yield increases but, on average, these increases were uneconomic. Sulphate of ammonia applications increased cyst populations, especially when applied at seeding, and urea had only a marginal influence on cyst numbers. Barley (cv. Weeah, Prior, Noype ) gave the highest yields on nematode-infested soils, followed by wheat (cv. Insignia), with oats (cv. Avon, Irwin, Swan) having the poorest yields. However, the cyst populations after oats were considerably lower than after barley which, in turn, was lower than after wheat. These differential cyst populations were reflected in a subsequent wheat crop.