Unseasonal hot weather reduced the yield potential of many Western Australian canola crops this year, but research could help deliver varieties with better heat tolerance in the future.
Recognising that canola is vulnerable to heat stress, particularly at flowering time, the Grains Research and Development Corporation (GRDC) is supporting canola heat tolerance research at The University of Western Australia (UWA).
The research started in 2013 and is part of the National Brassica Germplasm Improvement Program which aims to provide canola breeders with advanced genetic material, incorporating new or improved traits, so Australian growers have access to cultivars that allow them to compete effectively on world markets.
“WA canola crops – particularly in the northern and eastern grainbelt – suffered from heat stress this season, and this is likely to happen again in future seasons,” UWA Institute of Agriculture and School of Plant Biology researcher Sheng Chen said.
“The damaging heat stress occurred when the canola crops were at the early flowering stage.
“Severe heat stress during flowering reduces canola seed yield and affects seed quality, and next year we should have sufficient data to quantify the effect of heat stress on canola seed yield and quality.”
Dr Chen and his colleagues are in the early stages of screening more than 100 internationally-sourced canola lines – from places including Europe, China and India - in a bid to identify lines with good heat tolerance.
“We hope to isolate lines that are more heat tolerant than existing Australian commercial lines and which can be used in Australian canola breeding programs in coming years,” he said.
The heat tolerance trials are taking place in ‘Controlled Environment Rooms’ (CERs) and in the field.
In the CERs, the canola lines are being subjected to five different temperature combinations at flowering time, including high temperatures of 25°C, 32°C and 35°C.
Dr Chen said it was too early to determine which canola lines had superior heat tolerance, but independent research led by Wallace Cowling at the UWA Institute of Agriculture had identified some heat tolerant lines of Brassica rapa, an ancestor of canola grown as an oilseed or vegetable crop in some countries.
Professor Cowling said the research involving Brassica rapa had been conducted at UWA since 2008, and had been supported by the Australian Research Council (ARC) Linkage Project scheme and industry partners since 2011.
“The goal has been to find heat tolerance genes in Brassica rapa, as these could easily be transferred into canola lines by plant breeders,” he said.
Sheng Chen, UWA
08 6488 5928, 0423 238 218
Natalie Lee, Cox Inall Communications
08 9864 2034, 0427 189 827
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