CANOLA has become ‘the’ crop when it comes to cropping rotations – but it is not necessarily all smooth sailing.
Pod shatter poses plenty of problems, but Nuseed senior analytical chemist Jason McAllister tells North West Farmer canola growers and their advisers can be equipped with the knowledge and tools to make more informed decisions on pod shatter tolerance when selecting varieties.
Recent grower research conducted by Nuseed found 55 per cent of those surveyed are seeking increased pod shatter resistance due to its impact on productivity through seed loss and reduced yields.
Already earlier maturing varieties and farming practices now allow canola to be grown in much drier environments, such as the Mallee.
Mr McAllister said Nuseed had developed new technology and methodology to measure pod shatter while also bringing to market commercial varieties with improved tolerance.
“Our development of a scientific methodology for rating canola varieties on pod shatter tolerance will tangibly help growers mitigate risks by making more informed crop planning decisions for farmers across northwest Victoria – and most of the southern agricultural zone,” he said.
“Not only does it give growers and their advisers data-driven information to select varieties on pod shatter tolerance, alongside other desirable traits such as yield, oil levels and disease resistance, but it also helps our plant breeders bring new seed products to market with shatter resistant canola lines.”
Mr McAllister said having identified a “clear gap in the industry”, with there being no standardised industry test or rating system to measure pod shatter tolerance, Nuseed had developed a robust shaking methodology.
“Over the years, the industry has relied on a number of in-field and lab-based methods, which have had varying levels of success,” he said.
“Realising the industry needs a simple and reproducible test with a high degree of accuracy, our team of scientists developed a method that has not only proven to be accurate, consistent and repeatable, but can grade plant lines.”
With many variables to consider, in terms of the impact of pod maturity and the shape, length and quality of the pod itself on shatter resistance, Mr McAllister said humidity was also a significant factor.
To control these variables, as well as those in the lab, he said Nuseed had rigorously tested and refined their methodology, which included conducting the test over three different time intervals to see how fast the pods shatter over each respective period.
“The first step of the process involves collecting 30 representative pods from one mature canola plant, which we then sub-sample by selecting 20 pods,” he explained.
“The pods are then pre-conditioned in an oven at 40 degrees for 24 hours to standardise their moisture content, which allows us to assess the worst this plant line is going to perform.”
After placing the pods in a plastic container, Jason said they then load the containers into the Geno/Grinder whereby the pods were shaken in a vertical up-down motion at 1000 RPM at 30, 60 and 90 seconds.
“We then score each 20-pod sample according to the amount of seed loss that occurs after each time period, at which point they are ranked via a rating scale from susceptible through to tolerant,” he said.
Nuseed regional market development manager Michael Hickey said not only did this methodology help growers and their advisers compare canola varieties on their relative levels of pod shatter tolerance, but it enabled development of new varieties with enhanced resistance levels.
“Our recently-released Nuseed Hunter TF variety has enhanced pod shatter tolerance, which will flow into better returns with the varieties’ improved yield and oil content,” Mr Hickey said.
“Farmers no longer have to rely on anecdotal evidence or historical performance, rather their selection can be based on the inherent pod shatter resistance of specific canola varieties.”
Armed with this knowledge, Michael said northwest Victorian farmers could now optimise their crop planning.
“This includes selecting the most suitable canola varieties for specific paddocks, and tailoring planting schedules – such as planting those most susceptible to pod shatter first – to minimise susceptibility,” he said.
