MM1: Long-term Permanent Fertiliser Experiment
Objective
To determine the long-term effect of superphosphate on wheat yield response. The experiment commenced in 1940 and until 1959, was conducted on a 3 course rotation of fallow – wheat – oats, to which superphosphate was applied to the wheat only.
Key activities in current program
The wheat variety Insignia, which was originally used is still being grown in the experiment. In 1960, the rotation was changed to a two - course fallow – wheat system (Table 3). This rotation appeared likely to deplete nitrogen reserves in the soil, with the possible consequence that nitrogen may become a limiting factor in producing responses to phosphate. Thus in 1960 plots were split for the application of nitrogen fertiliser. In 1987, the plots were split and under sown with Paraggio medic and the level of response to phosphate can be compared between the two medic treatments. There are now 2 separate sites located in different paddocks, so in any given year, one trial is in crop or fallow. Grain yields and protein levels from each treatment are measured for the cropping cycle. Soil surface analysis is also recorded for each treatment. An understanding of the effects of repeated applications of superphosphate over a long period is desired out come from these long-term trials. The long-term use of phosphate fertiliser and build up of cadmium is also being monitored. However, as the soils are alkaline, only minimal plant uptake would occur.
© The State of Victoria, 1996 - 2009.
This document was last reviewed on 18/08/2009