CHICKPEA crops in southern Australia and isolated parts of northern Australia are being hit by a more virulent strain of the damaging ascochyta blight.
Pulse pathologists in Victoria and South Australia have noted a marked decline in the resistance of several varieties of chickpeas, with varieties previously rated as moderately resistant performing like susceptible lines.
Pulse agronomist with Agriculture Victoria Jason Brand said there was a new isolate in the ascochyta pathogen that meant it behaved much more aggressively.
He said at present the breakdown in resistance was limited primarily to chickpea crops, although compromised resistance has been noted in some lentil and faba bean varieties.
“It is less than ideal, but at least it is being well controlled by fungicide applications,” Dr Brand said.
Former Pulse Australia representative Gordon Cumming, now with the Grains Research and Development Corporation (GRDC), said chickpea growers in the northern region were watching ascochyta closely.
“It is a wetter year and hence a higher pressure disease year all round, but we have only seen an isolated patch where the ascochyta is breaking down resistance around Yallaroi and North Star in northern NSW,” Mr Cumming said.
“Farmers can get on top of it, but what we are finding is that it is a lot less forgiving than in other years, you really have to keep up to date with the fungicide program.”
He said, similar to in southern areas, the resistance breaking blight was not technically a new strain, but the same one, expressing itself more aggressively.
Dr Brand said the pulse industry had been ready for the increased vigour of the disease for over a year.
“We noticed last year in chickpea trials some breakdown in resistance, even though last year was not a big year for ascochyta, so we were preparing for it this year when conditions are much more favourable for the disease.”
Dr Brand said farmers had been proactive in controlling the disease with a fungicide and said there were adequate fungicide stocks in southern Australia.
“Hopefully, providing there are no issues with paddock access, it should not be a big problem in terms of yield losses.”
Chickpeas are a relatively boutique industry in southern Australia, with acreages only slowly rebounding following the ascochyta attacks that decimated the southern chickpea sector in the late 1990s.
Five-year average acreages for desi and kabuli chickpeas combined are only just over 20,000 hectares in Victoria and just under 15,000ha in South Australia, compared to the hundreds of thousands of hectares of desis in northern NSW and Queensland. Lentils are the more popular high value pulse in the south.
Dr Brand said it was now difficult to identify accurate resistance ratings for southern chickpea varieties.
“We will need to do some tests and see which ones stand up best to the blight as it presents now – it’s a similar story to when you see a breakdown in rust resistance in wheat, it takes time to sort out.”