Hatching of Western Australia Populations of Cereal Cyst Nematode, Heterodera Avenae, and Effects of Sowing Time and Method of Sowing on Yield of Wheat.

Abstract

The hatching pattern of a Western Australian population of Heterodera avenae was compared with published information on South Australian and Victorian populations. The optimum temperature for phase 2 of hatching of the Western Australian population was near 15°C and the optimum temperature for phase 1 was probably near 10°C. Hatching of eggs collected from the field between November 1988 and May 1989 and kept in water at 15°C showed a marked increase in hatching in samples collected on or after 20 January. In Western Australia, the peak in numbers of second-stage juveniles in the field occurred in late May but some juveniles were present in soil as early as January. Later sowing in 1987 reduced the yield of wheat on soil infested by H. avenae. Yield was not affected by the number of cultivations before sowing.