Seed grading is under way and, as the wheat is literally sorted from the chaff, growers are reminded that the quality and size of that seed can have a significant effect on future crop performance.
GRDC has compiled a handy resource, the Retaining Seed Fact Sheet, outlining factors growers need to consider before sowing, especially given many experienced wet conditions during the 2017-18 harvest.
Rain at harvest can reduce germination and vigour of retained seed, while seed is also at a higher risk of degradation during storage and handling.
Growers should be mindful that seed-borne diseases can damage seed and have a lasting effect.
The fact sheet highlights:
- symptoms of poor quality can vary
- weather-damaged seed deteriorates faster, so should not be stored for more than 12 months
- grain that received a pre-harvest application of glyphosate must not be retained for seed
Growers can undertake their own germination tests, either in soil or on a piece of paper towel.
It is not only the quality of the grain that needs to be considered, but also the grain weight, according to BCG project manager Louisa Ferrier.
“Growers should check the grain weight, germination of retained seed and calibrate accordingly to achieve consistent plant establishment from season to season” Ms Ferrier said.
In research conducted at the BCG main site at Curyo in 2017, Compass barley seed retained from 2016 and 2015 was put to the test.
“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 the exceptional spring rainfall,” Ms Ferrier said.
The premise of the trial was to identify significant differences in yield or quality if a grower didn’t calibrate their seeder from season to season.
Ms Ferrier explained that “the pub test” would suggest barley plants will compensate for the lower seeding rate with more tillers.
Grain was sown at the optimal plant population for cereals in the Mallee at 130 plant/m2, which for the Wimmera would be 150 plants/m2 and 150-200 plant/m2 for the high rainfall zone, and was compared with grain sown at uncalibrated seeding rates.
“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,” Ms Ferrier said.
BCG members can discuss the trial with Ms Ferrier at the trials review day in Birchip on February 16.
