Adequate rain during the growing season has ensured BCG research trials at Longerenong have ripened well for harvest, which started last week.
Maturity cuts have been carried out on a range of trials including canola phenology, barley plant growth regulators and barley nitrogen timing.
Maturity cuts are taken to measure the weight of biomass just before harvest. These results can then be used for harvest index, which measures the biomass to grain ratio between individual varieties and different treatments.
Fortunately, the severe frost experienced throughout most of the Wimmera did not affect the Longerenong research trials, although a Grdc-funded managing-early-sown-wheat trial had damage from a previous frost.
The Grdc-funded National Frost Initiative is a five-year project aimed at tackling frost from several angles and delivering growers a combination of genetic and management solutions to mitigate frost, together with tools and information to better predict frost events.
This year, BCG has two trials, at Murtoa and Corack near Donald.
The trial at Corack – frost prone paddock – is a plot sown trial with six wheat, three barley and three oat varieties.
The trial is investigating the effect of different crop types at three sowing times.
The first time of sowing, early, was sown on April 19, second sowing was on May 1 and the last sowing time, late, on June 1.
The trial encountered several frosts during the grain-filling period in August and September, resulting in severe frost damage in the first and second sowing times. All crop types were affected including the oats, but this was a pre-heading frost at second-third node.
The trial could potentially now look at different crop types compensatory ability – secondary tillering that contributes to yield – after major frost damage.
The other frost trial at Murtoa is a farmer-scale trial sown to Scout wheat, investigating two different seeding rates and three nitrogen strategies.
The trial has only experienced mild frosts leading up to November, so only mild frost damage has been evident.
The trial was sown into lentil stubble and it was observed that where stubble load was high, frost damage was more severe.
Past research has shown high stubble loads increase the severity and duration of frosts.
This is because the stubble reduces the amount of heat captured in the soil and results in the potential for more severe and longer frosts.
Growers should be aware, however, under severe and frequent frost events, the benefits of stubble reduction to mitigate frost could be less because it only influences temperature slightly.
Both trials have had anthesis cuts undertaken and are currently undergoing floret sterility scoring to assess the amount of frost damage present.
For further information on the GRDC National frost trials or other trials, people can call BCG on 5492 2787.