QUINOA trials in the northern and central Wheatbelt last season may have been disappointing, but it seems the Department of Agriculture and Food (DAFWA) is having more luck with its spring-sown crop in the State's South West.
DAFWA's Manjimup crop was planted in early October, and escaped the frequent low minimum temperatures that are believed to have impacted yields at trial sites in Cunderdin and Mingenew.
The trials are part of a research project funded by the Rural Industries Research and Development Corporation (RIRDC) to assess the feasibility of adding quinoa as a permanent fixture to the Australian crop .
Three advanced lines of quinoa were developed and trialled, along with WA-based Three Farmers' variety Medusa.
DAFWA research officer Richard Snowball said with the help of irrigation and mild weather, the Manjimup trial was signalling more positive results.
"It's a good environment down there - most of the material we have is sourced from the mediterranean part of Chile so those places are quite similar in climate to the Manjimup/Margaret River area," he said.
"Also in the mediterranean part of California where they grow quinoa, it's a spring-sown crop - so I wanted to simulate what happens there."
With supplementary irrigation the crop received close to the average Manjimup monthly rainfall of 46 millimetres in November and 25mm in December.
Mr Snowball expected the pseudo-cereal crop to be harvested in late January, and reap higher yields than trials in Mingenew and Cunderdin.
Trial crops in Mingenew were sown over April, May and June and harvested in September and December, yielding up to 300 kilograms per hectare.
The Cunderdin trial crops also suffered disappointing results after being planted in May and June, with yields peaking at 50kg/ha when harvested in mid-December.
Mr Snowball said results suggested the low quinoa yields were due to cold temperatures during the plant's flowering stage.
"This past year was very cold and the crops were affected not only by frost but many low minimum temperatures around 2 or 3C during the flowering time - that seemed to be what was affecting the yield in both of those trials," he said.
"It still germinated and grew during the winter time even though we had lots of frosts and very cold temperatures during June and July - but the critical thing is temperature during the flowering time.
"In average or warmer than average years, quinoa may escape this problem. Another solution may be to sow later in July, however the crop may be exposed to high maximum temperatures during flowering, or run out of moisture."
Despite more ideal conditions throughout the growing season in Manjimup, Mr Snowball said the spring trial had not escaped the impact of weeds.
"The problem weed is Fat Hen. It's very similar to quinoa and there's a lot of it on the research station so we had to go through and pull out a lot of those plants," he said.
"It's difficult to treat the weeds because they're closely related to the quinoa plant so you can't use herbicides.
"It's a matter of preparation - you need to prepare your paddocks for a couple of years at least to remove that weed burden as much as possible and prepare well in the planting to give the best possible chance of a weed-free site."
Mr Snowball planned to conduct more quinoa trials across the State in 2017.
"I'm planning on doing a greater number of smaller trials over a larger area to try and get a better idea about the impact temperature has on the yield," he said.
"I think I'll do another trial in Manjimup and I'll probably do some earlier sowing in September and see if the crop will grow through without any irrigation. I think there's a fair chance it will."
He said although a colder than average 2016 had an adverse effect on the trials, the addition of quinoa as an alternative crop in WA was a reasonable prospect.
"I think in the northern Wheatbelt it has a chance and in coastal areas where it is mild and they don't really have frosts," Mr Snowball said.
"That's rain fed, I think if you have irrigation you have a lot more scope because you are guaranteed a good yield and you can spring sow, so you escape the cold September."