Wheat growers who have completed seeding now have the opportunity to assess crop establishment and reflect on the effectiveness of their sowing strategy.
A trials program involving Department of Agriculture and Food (DAFWA) wheat agronomy and soils researchers is examining how seeding conditions influence crop establishment on repellent soils.
DAFWA research officer Christine Zaicou-Kunesh said growers’ ideal establishment target ranged from 100-180 plants/m2, depending on location and yield potential.
The trials, supported by the Grains Research and Development Corporation (GRDC), are examining crop establishment based on time of sowing, whether crops are sown into dry or wet soils, and the use of wetting agents.
Plots have been planted this season at Binnu, Eneabba, Cranbrook and Wickepin, in collaboration with growers and groups including the Northern Agri-Group, West Midlands Group, Facey Group, Gillami Centre, and Living Farm Group.
“Early results from trials at Binnu show plant establishment is less when dry sown, compared with plants sown into wet soil at the same rate,” Dr Zaicou-Kunesh said.
“When Mace was sown at 60kg/ha into dry soils, 86 plants per square metre established compared to 108 plants/m2 when sown into wet soil two weeks later. However there was no difference in establishment when Mace was sown at 120kg/ha. Plant establishment averaged 150 plants per square meter when sown dry or wet.
“These trial sites will continue to be monitored throughout the season. This work will assist growers to better understand the risk factors with dry and early sowing and agronomy to manage, as well as the economics behind the choices they make.”
Non-wetting soils researcher Steve Davies said growers and researchers had found furrow sowing with knife points on water repellent sandplain soils was often ineffective with poor crop establishment.
“The problem appears to be caused by dry repellent soil flowing around the knife point and being concentrated with the seed and fertiliser in the base of the furrow. The problem is exacerbated in severely repellent soils when dry sowing or in seasons with a dry start.
“In general, growers have increased seeding rates with the expectation of increased establishment in these situations in an effort to ensure plant numbers don’t limit productivity.
“An alternative solution to improve establishment on repellent soils may include the use of banded soil wetting agents. There are a number of types of wetting agents with different properties for aiding water penetration as well as retention of water and nutrients. These are being examined as part of this trial program.”
The findings from the trial will be incorporated into DAFWA crop management packages and tools.
Growers can stay up to date with crop management information during the season by reading DAFWA’s AgTactics and AGMEMO newsletters, available at agric.wa.gov.au and attending regional field days.