Previous PageTable Of ContentsNext Page

Lime application increases the risk of take fall

J.E. Pratley1 and G.M. Murray2

1 Riverina-Murray Institute of Higher Education, Wagga Wagga, 2650
2
Agricultural Research Institute, Wagga Wagga, 2650

Application of lime is the standard method of raising pH of acidified soils to levels of improved productivity. Such a practice does not guarantee this improvement because conditions are also more suitable for some pathogens, notably take-all (Gaeumannomyces graminis var. tritici). Yield depressions in wheat due to take-all have been observed in central and southern NSW where soil pH (1:5 water) is raised above 5 (2) and at Rutherglen, Vic. (1), following liming.

Methods

At the Riverina-Murray Institute, Wagga Wagga, lime (2.5 t ha-1) was applied in April 1984 to a clay-loam soil of pH (1:5 water) = 4.6, 0-10 cm. The area was successively cropped with barley and two wheat crops. The incidence of take-all was measured in December 1986.

Results and Discussion

The level of take-all is shown in Table 1.

Table 1. The effect of lime application on wheat tiller number, take-all incidence and silver grass biomass

The presence of a large biomass of silver grass (Vulpia sp.) provided a source of infection to the crop. At the higher pH level following lime application, conditions suitable for severe take-all occurred. These findings emphasise the importance of good agronomy in controlling grass weeds in order to maximise the benefits of soil amelioration.

8. Coventry, D.R. and Kollmorgen, J.F. 1986. Rutherglen Research Institute, Research Report 1985-86, Dept.Agric.Rural Affairs, Vic.:74.

9. Murray, G.M., Scott, B.J., Hochman, Z. and Butler, B.J. 1987. Aust.J. Exp.Agric. 27: in press.

Previous PageTop Of PageNext Page