DALE WEBSTER, The Weekly Times
INTRODUCING break crops to rotations in low rainfall areas has been shown to increase annual wheat profits by up to $100 a hectare.
Mallee Sustainable Farming agronomist Michael Moodie says trials have demonstrated that where issues such as weeds, declining soil fertility and root disease have been affecting wheat yields, introducing a break crop into the rotation can mitigate those issues in following seasons.
He says benefits were seen in one year but the best results were from two-year cycles of a legume.
“The wheat yield benefit was one to two tonne a hectare,” he said. “After a single break yield it was under 0.5 tonne per hectare but after a two-year break, it was 0.5 to one tonne per hectare.”
Mr Moodie said break crops in the low rainfall zone had provided similar benefits to what they did in the medium and high rainfall zones.
“If you grow a break crop or two in a rotation the following wheat crop’s production was increased one to two tonne per hectare — even in the low rainfall zone, where average yields might be around 1.5 to two tonne per hectare.
“This increase in production has led to increases in profitability of that rotation by up to $100 per hectare per year, which is quite significant in the low rainfall zone.”
The five-year trial was run over sites in the Victoria-South Australian Mallee regions and Central NSW, with each trial comprising up to 19 unique crop sequences.
Mr Moodie said one of the most interesting results was that there was no single specific “best bet” break crop that should be grown in a rotation to maximise yield and profits.
“It’s really about selecting a break crop that is going to do the job in terms of addressing the agronomic constraints that are present, as well as give you a good chance of making it a profitable enterprise in its own right,” he said.
Mr Moodie said field peas, chick peas and lentils had provided some “surprising” results in the Mallee sites over the past t
hree years in terms of what they might be able to achieve in a low rainfall zone.
Read more: http://www.weeklytimesnow.com.au/agribusiness/cropping/when-rainfalls-low-good-break-can-bring-rich-rewards/news-story/727f45c375f583684546db244ca0b98c