LOCAL farmers experiment with plant growth regulators to counter the growing problem of lodging in crops, writes PETER HEMPHILL

Winchelsea grain growers David and Tracey Langley believe plant growth regulators may become the next revolution in high-rainfall farming.

The Langleys tested the Syngenta product Moddus on 10ha field plots of both wheat and barley this year.

Moddus has been globally promoted as a means of countering lodging, which reduces grain quality and is a major problem in the Western District.

Syngenta said some of the other advantages growers could expect were higher crop yields, no need to use pick-up fingers on harvesters and better harvesting speed.

The field trial was instigated by Landmark agronomist Alistair Tippet, based at Bannockburn, near Geelong.

Alistair said Syngenta was looking for farmers to trial Moddus in large-scale field experiments and was offering use of the growth regulator under permit conditions.

David and Tracey, with sons Charlie, 16, and Will, 13, this year grew 350ha of derrimut and forrest wheat and 100ha of westminster barley, the latter yielding 5.3 tonnes/ha. They also planted 280ha of stingray and ATR gem triazine tolerant canola varieties, which yielded about 3.5-3.6 tonnes/ha.

About 1400 Merino wethers were run on the 1000ha property and 60ha were sown for ryegrass seed.

Consistently growing heavy crops means lodging is a risk to the Langleys' operation.

Alistair said Moddus was currently being registered by Syngenta for use on grain crops in Australia, but could be used for experiments under a permit.

He said Moddus was applied to 10ha plots of the Langley's crops at rates of 400ml/ha at growth stage 32 and 200ml/ha at growth stage 39.

"The growth regulator acts by directing plant energy into thickening the stalk," Alistair said.

Syngenta said lodging generally occurred during the last two to three months before harvest.

In the worst cases, it could result in grain yield losses of up to 80 per cent and could also affect grain quality.

The company said the growth regulator retarded the rate of plant growth to ensure the roots and stem thickness provided adequate support.

Alistair said lodging occurred on none of the plots treated with Moddus nor the untreated westminster barley on the Langley's property.

He said the crop was harvested prior to a major downpour a fortnight ago.

"After the rain, crops in the area did lodge," he said.

Alistair said gairdner was still the most popular barley variety but westminster was a new variety with higher yield potential.

"So it (westminster) might have more potential to lodge," he said.

David said the westminster barley treated with Moddus was about 15-20cm shorter than the untreated crop but he did not think at the time it would yield any better.

"I didn't think we would get a yield improvement," he said.

"To look at the crop, it didn't visually look any better but it must have put more energy into the grain rather than the stalk."

David said the untreated westminster barley yielded 5.3 tonnes/ha but the plot treated with plant growth regulator had a yield of 6.5 tonnes/ha.

He said the barley gains surprised him as it was difficult to visually notice any difference in yield between the treated and the adjacent untreated crop.

He said treated derrimutt wheat did not visually show any difference in crop height.

And there was no significant yield difference as well.

At face value, the application of Moddus to the barley crop appeared to have paid off.

At $200 a tonne for feed barley, the extra yield from the growth regulator amounted to $240/ha.

David said it was not clear how much growers would be charged for the growth regulator when it was commercially released next year, but it seemed like a positive investment.

Regardless of the effect of Moddus on their derrimutt wheat this year, David said the plant growth regulator might have applications for their forrest wheat, a new variety which they grew this year for the first time.

The 70ha of forrest they grew this year was yielding about 8-8.5 tonnes/ha - without growth regulator - when harvested earlier this week.

So thick was the crop, parts were already starting to lodge.

The derrimutt wheat yield suprised David, topping about eight tonnes/ha and 11.9 per cent protein.

He said the high yield in the forrest crop was probably due to adding plenty of nitrogen.

"We really stacked it on," he said.

That included 120kg/ha of mono-ammonium phosphate at sowing, followed by two applications of 100kg/ha of urea at growth stages 32 and 39.

Moddus might be a useful management tool when growing heavy yielding crops, such as forrest wheat.

"Our greatest risk in this area is from waterlogging," David said.

"So I wonder whether we can sow the crop early to give the crop a head start.

"If we let the crop get itself up early, then we might be able to slow it up with the growth regular later on.

"Later on, we can put more nitrogen on without it going into vegetative growth."