Stubble a key to high pulse yields

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By Felicity Pritchard
Pritchard Agricultural Consulting and Extension

While debates about ideal row spacing and stubble management continue, GRDC-funded trials are providing some answers to growers in the quest to fine-tune pulse agronomy. 

Project leader Dr Jason Brand, from the Victorian Department of Primary Industries, is excited about the tri-state research across the GRDC southern region, showing pulses are adaptable to a range of sowing widths, depending on the farming system.

According to Dr Brand, standing stubble is the key to higher yields with wide row cropping of pulses.
“We found massive benefits in pod height and ‘standability’ when inter-row sowing lentils into standing stubble and no yield loss from 30-centimetre spacing. The biggest improvement was in the lodging-prone variety Aldinga,” Dr Brand says.

For lentils, widening rows from 20 to 30cm made no difference to yields in 2009 but boosted yields in 2007 and 2008 – both years with very dry finishes in the Wimmera. Results from 2010 are likely to differ again due to the wet season.

The research also finds standing stubbles can benefit chickpea yields by lifting pods, making them easier to harvest with better ground clearance and plants less prone to fungal disease.

The presence of standing stubbles, compared with slashed, boosted chickpea yields by 10 per cent in 2009 trials at Minyip in Victoria’s northern Wimmera in a very low-yielding year. But row spacing up to 60cm made no difference.

“Our research shows it’s really ‘horses for courses’,” he says. “Farmers can make an informed decision based on their own farming system.”

One benefit of wide rows in pulse crops is improved aeration. This reduces disease pressure and aids good coverage of fungicides and herbicides within the crop canopy.

“From a disease management perspective, chickpeas are one of the crops that really do benefit from wider rows, like faba beans, in conjunction with retained stubble,” he says.

Luke Gaynor, of Industry and Investment NSW, says that historically Riverina growers have sown crops around 18cm (seven inches) but the trend is for wider rows, with 30cm the most popular choice.

“This is primarily to improve the machinery’s ability to handle larger stubble loads without affecting crop emergence due to blockages,” Mr Gaynor says.

Some Riverina growers are even now opting for 38cm rows, he says.

Trials at Yenda and Wagga Wagga in the dry years of 2007 to 2009 showed – for field peas and chickpeas – very little yield difference between 20 to 30cm spacings. In some cases 30cm was optimum.

Faba beans are more adaptable over wider rows, with only 50cm showing some yield decline in some years.

Mr Gaynor expects completely different results from 2010 trials with well-above-average rainfall for NSW as crops may lose potential yield from wide rows in high-yielding environments.
In South Australia, SA Research and Development Institute (SARDI) trials at Tarlee showed an average 13 to 15 per cent yield increase in faba beans sown at 23cm compared with 45cm at the high-yielding site in the mid-north high-rainfall zone. However, individual grain weight was reduced with narrower rows. For the variety Nura, the yield effect was far less marked with three per cent increase with narrow rows.

Like the effects of row spacing, high-rainfall environments are bringing different results from dry sites when it comes to sowing dates.

Mr Gaynor says early sowing consistently improved yields in southern NSW trials in the dry years of 2007 to 2009. But he says 2010 may show different results due to excellent growing conditions resulting in massive plant biomass, increased disease pressure and some severe lodging of early April sown treatments.

“From data collected this year, combined with our previous dry season results, we will be able to show what is the ‘best bet’ sowing date for pulses in southern NSW,” he says.
While the 2010 trials are not yet harvested at the time of writing, early sown trials are running into problems.

“Our field peas, chickpeas and faba beans sown in early April at Wagga Wagga and late April at Yenda have crashed. They have huge biomass. They’ve lodged and are diseased, even with our regular fungicide applications,” he says. “Chickpeas, however, have probably held up the best across all sites.
“The second and third times of sowing appear better,” he says.

The research is continuing and hopes to give growers management strategies for individual pulse varieties to tie in with different farming systems – no-till or minimum-till – in a range of environments across the GRDC’s southern region. 

GRDC Research Code DAV00113
More information: for a copy of the Southern Pulse Agronomy Annual Trials Report contact Jason Brand,
03 5362 2341, email, or Luke Gaynor, 02 6938 1999, email;

GRDC Project Code DAV00113

Region South, North, West