While the BCG plot harvesters are currently making their away around the various BCG research sites in the Mallee, harvest of a different kind is also occurring in the Wimmera.
On 25 October the first maturity cuts (a method of taking a small quadrat sample of a mature crop) were collected from particular plots as part of the GRDC Optimising Canola Profitability project at Longerenong. A week later, the header harvested BCG’s first trial at Kinnabulla in the southern Mallee.
Maturity cuts started in the Wimmera so early because some of the plots were ripe. This early maturity is a result of some of the eight varieties, two sowing dates and two nitrogen application timings favouring an early finish, remaining plots will mature at later dates.
To get the most out of these trials, yield information needs to be collected at the maturity of various maturities.
If the whole trial was left until all the final treatment matured, the resulting yields would benefit longer season varieties.
Collecting maturity cuts also allows researchers to collect the whole plant, meaning not only are yields collected, but a harvest index (the ratio between grain and dry matter produced) as well.
Harvest index is the ratio of straw to grain. It provides an understanding of the reproductive efficiency of the plant i.e. how well it turns green leaf matter into grain.
There are many factors that influence harvest index including the energy and protein content of seeds, long-term breeding achievements, extreme temperatures, delayed sowing and more.
Delayed sowing shortens the length of the vegetative phase resulting in less plant matter to grain as a ratio, and therefore harvest index would be higher.
Most importantly for the grower, yield data is collected to assess canola varieties and management strategies.
Two other trials in the Wimmera from which maturity cuts were taken are the GRDC Development of Crop Management Packages for Early Sown, Slow Developing Wheats in the Southern Region and the GRDC National Frost Initiative.
