WHILE crop growth has been accelerated this year, there is concern that there will be hidden hunger issues later in the season.
CSBP market support manager David Matthews said CSBP had only received an average number of plant samples from farmers into its Bibra Lake laboratory this year compared with the past five years.
He said while plant analysis was useful to monitor the supply of macronutrients such as nitrogen, it was also the best way to check on levels of trace elements in winter crops to ensure that these nutrients were not likely to limit yield.
"In the very good season WA is experiencing at the moment, plants grow quickly and can become deficient in certain nutrients because larger plants have a greater requirement for food," he said.
"For example, cereal plants can look healthy but actually have deficient levels of copper, which shows up late in the season as poor head fill.
"Such poor yield can be blamed on frost, whereas it could be a copper deficiency and without analysis farmers can't be sure."
Mr Matthews said hidden hunger occurred when there were no deficiency symptoms but the plants would not yield to their economic potential.
"By the time plant deficiency symptoms are visible, significant yield has already been lost."
He said there was still time for farmers to check if their crops were getting enough nutrients from their soils to finish the season.
A GRDC-funded project into trace elements started this year and is being delivered through a CSBP, Murdoch University and Department of Agriculture and Food (DAFWA) partnership.
DAFWA principal research officer Ross Brennan said the trial would assess whether trace element applications had kept up with the evolution of farming systems.
"Farming has changed from the days when trace element recommendations were developed as we've moved into more intense cropping, higher yields, higher nitrogen use and minimum tillage," Mr Brennan said.
"There's a need to look at the old data and do more experimental work to see if the original advice is still relevant today."
Each trial includes up to 18 different fertiliser treatments, designed to test a range of application methods.
"We're looking at a range of micronutrients, such as copper, zinc, manganese and boron in wheat as well as boron in canola, just to see what the response is," Mr Brennan said.
"We're looking at different application methods, including micronutrients applied with seed, fertiliser, foliar sprays and combinations of those to see where and when we reach our maximum yields."
CSBP is running 40 trials across the State this year.
CSBP field research manager James Easton said the 2016 trial was targeting crop nutrition, with some pasture nutrition trials.
"Our main focus this year is looking at more effective ways of supplying potassium, however, we're continuing to do a lot of work with the trace elements," he said.
Mr Easton said some of the most significant findings were with copper.
"We've found that liquid applications of copper at seeding time have been significantly more effective than the granular applications," he said.
"However, with manganese, we're finding that granular applications are more effective than liquid applications at seeding time."
At a granular manganese trial in Scaddan in 2015, seeding liquid applications of manganese gave a minimal response, while a produced an extra 600 to 700 kilograms a hectare of wheat.
Post-seeding, Mr Easton said trial work was indicating that foliar applications of copper and manganese were effective, but it was important that rates were high enough to overcome deficiencies.
Many trials in 2016 will look at the residual value of trace element applications and while those results are yet to be published, Mr Easton said plant tissue testing still remained critical.
"Farmers can't assume that what they're doing is effective and they should be plant testing to check the effectiveness of their fertiliser strategy, and particularly their trace element strategies," he said.
