Farm Table says:
What is the problem?
The use of annual-based pasture and/or annual crops is now common practice in the higher rainfall regions of southern Australia where livestock grazing is the traditional practice. The lower water use of these annual-based systems, compared with systems based on perennial pastures, exacerbates issues of waterlogging, rising water tables and salinity in these regions. For environmental reasons farming systems used in the higher rainfall regions should target the use of more perennials in the landscape, but this should not be done at the expense of farm productivity or profitability. A study of crop/perennial pasture intercrops is the core investigation undertaken in this thesis.
What did the research involve?
Perennial pasture species lucerne and chicory were established and maintained for three seasons with annually sown crop species, Lupin, and canola, in a double skip row arrangement.These intercrops were compared for production, resource use and farm productivity with the individual crops and pastures grown as monocultures.
What were the key findings?
Yields of grain crops were reduced when grown in intercrop with lucerne and chicory. Grain yield reductions ranged from 0-46% for wheat, 45-74% for lupins and 8-83% for canola. Pasture dry matter was also reduced when intercropped. Despite the reduction in crop and pasture production, the Land Equivalent ratio ranged from 0.71-1.66, with all intercrop combinations over-yielding in favorable growing seasons.
It is concluded that competition for water was the main resource competition responsible for yield reductions in intercrops