With strong grain prices at present, having an understanding of the seed size and 1000 grain weight of seed harvested this year will be important.
This information can assist in ensuring growers hold on to enough seed as required for the 2019 season, without forgoing the opportunity for increased revenue this harvest.
Seed size will likely be affected by the lack of rainfall during the 2018 season, with germination also something to keep in mind.
In 2017, a comparison was undertaken with seed from 2015 (decile 1 season) and 2016 (decile 10 season), to investigate if savings could be made by ensuring the optimal amount of seed was used at sowing.
BCG’s Engagement and Member Services Leader, Louisa Ferrier, explained the trial conducted at Curyo was sown with two very different Compass barley seed sources.
“Grain retained in 2015 was small, 33.5g/1000 grain weight, because of the dry season. While 2016 seed was large, 58.5g/1000 grain weight, because of exceptional spring rainfall,” Ms Ferrier said.
It was determined the small seed should be calibrated at a rate of 51kg/ha and the large seed at 90kg/ha to achieve optimal plant populations.
When calibrated to achieve the optimal plant population for cereals, which has been shown to be 130 plants/m² in the Mallee, 150 plants/m² in the Wimmera and 150-200 plants/m² in the high rainfall zone, there was no difference in the yields of the two seed sizes.
“The trial yielded an average 4.7t/ha across all treatments and we did see a difference between the optimal sowing population and the sub-optimal sowing population.”
“However, major efficiencies were achieved by ensuring seeding rates were accurate and not wasting a product that could otherwise be sold,” says Ms Ferrier.
The treatments sown with 40 kg/ha excess seed had slightly lower retention due to the 200 plants/m2 density. This was not enough to result in a grain quality downgrade, however $8/ha worth of income was wasted to sowing (based on a $202/t price).
Income could be higher this year if grain prices continue to stay strong, therefore keeping grain size in mind at harvest could prove beneficial to growers.
This article was published in the Stock and Land, 15 November.
