CROPS can't do without them and neither can humans.

Trace elements are important to crop growth but also have a big impact on human health in developing countries where grain is almost the sole diet.

    AT A GLANCE
  • Who: Evan Ryan
  • What: crops
  • Why: trace elements linked to human health
  • Where: Yarrawonga
  • Report: PETER HEMPHILL

Yarrawonga farmer and Nuffield scholar Evan Ryan believes it will only be a few years before some countries demand Australian wheat with high levels of trace elements - such as zinc, selenium or iron - and pay for it accordingly.

Evan said it would happen once buyers realised the detrimental impact on human health from trace-element deficiencies.

"Already, the World Health Organisation has estimated that half the world's population is deficient in zinc and iron - in some cases, it is a severe problem," he told the Grain Growers Association's recent Innovation Generation conference in Albury.

Evan spent last year travelling the world studying the link between trace elements in soils, plant growth and human health.

He found people were more prone to health problems if they relied heavily on grains as the major part of their diet.

The problems included reduced appetite, stunted growth, anaemia, skin lesions, cancer and cardiovascular disease, to name a few.

"It is more prevalent where people are eating cereals day in, day out, three meals a day," Evan said.

"It is not as prevalent in developed countries because the diets include eggs and vegetables.

"But it is there as an undercurrent. It is just not as severe as what it is in developing countries."

Evan said some of the world's trace-element problems have their links back to the "green revolution" of Nobel peace laureate Norman Borlaug in the 1960s.

Dr Borlaug developed the high-yielding, disease-resistant semi-dwarf varieties of wheat, which was instrumental in heading off starvation in many parts of the underdeveloped world.

But work at Rothamsted Research in the UK - the world's oldest agricultural research institute with scientific records going back as far as 1845 - had shown copper and zinc levels in wheat grain had fallen dramatically since the early 1960s when semi-dwarf varieties were developed.

"While semi-dwarf varieties increased the volume of food, it didn't actually increase the mineral content or quality of the grain," Evan said.

He said selenium deficiency in diets was linked to cancer and cardiovascular diseases in humans.

He said many European countries fell below the optimum level of selenium for cancer prevention.

"Finland had huge problems with cardiovascular diseases," he said.

"When the (Finnish) Government found out about it, it passed legislation requiring that all fertiliser had to have selenium in it.

"It fixed their problem (with cardiovascular disease)."

Trace elements were also a key to crop growth. While zinc caused human health problems, it also affected germination of grain.

Evan said leading research scientist Ismail Cakmak, of the Sebansci University in Turkey, found zinc deficiencies in grain.

"Turkey had a zinc problem in its soils and no one knew what it was," he said. "The government legislated to put zinc in fertiliser and it doubled its yields overnight."

Dr Cakmak was also working on the international HarvestPlus project, which was "biofortifying" crops such as wheat, cassava, maize, rice and sweet potatoes with zinc, iron and vitamin A.

He was using genetics from wild wheat varieties, which had been shown to be highly efficient at transferring zinc from soil into grain.

Evan has been running trace element trials on the Yarrawonga farm he runs with his parents, John and Helene.

These trials have focused on the agronomic side of production and the effect trace elements have on boosting crop yield.

He has added molybdenum, copper and zinc to his crops to determine their impact on growth.

But dry springs have clouded results and he is looking forward to a season of more normal weather.

Evan said trials with high levels of zinc applied to his crops had shown better early vigour and growth and less disease.

He had not analysed his grain to see if it had higher mineral contents but would like to see that work done.

At least one Australian flour miller was interested in buying grain "bio-fortified" with selenium for health-conscious consumers.

Evan is convinced overseas buyers would head down the same path when the world became better educated on human health.