GM considered to remedy field pea disease

20 June 2013. Source:

A SCIENTIST with 20 years experience breeding field peas (Pisum sativum L.) recommends genetic modification research to mitigate the effects of black spot (Didymella pinodes).

“We have made significant progress in developing moderately resistant varieties of peas but more robust resistance has been illusive,” Professor Tanveer Khan says.

Prof Khan, who is now a research professor at The UWA Institute of Agriculture, has just led a review of international methods trialled to combat the disease, which he says have only been partially successful for growers in Australia.

He says black spot is endemic to most areas of the country planted with field peas.

The fungus survives on pea stubble, releasing spores into the air with the first winter rains.

Prof Khan says yields are relatively low in Australia, so it is not economical to apply fungicides to growing crops although there has been some success with applying fungicides to the seeds themselves.

He says a more successful method in Australia has been to delay sowing for two to three weeks after the first winter rains, after which time most of the spores have been released and fallen on to the soil rather than the growing plants.

The disadvantage of this method is a reduction in crop yield of up to 25 per cent, due to the limited growing season.

Prof Khan says climate change may bring more summer rains which would tend to exhaust most of the spore before pea planting season, however the amount of winter rain and consequent effect on pea yields is unknown.

He says breeding for resistance has had limited results, producing partially-resistant varieties of pea which he recommends be trialled for earlier plantings and/or single fungicide spraying.

Research is in progress to develop molecular marker technology to help development of resistant varieties but he says there have been no major breakthroughs so far.

“A remote possibility is, can you actually have a big breakthrough with genetic modification?” Prof Khan says.

“Can you actually import some resistance from some other alien species into peas?

“I think there’s a good reason why we should invest in some very novel technology.

“In Western Australia there are about 70,000ha grown.

“If we are able to control black spot in future we’re going to see peas becoming a very big crop.

“Potentially peas are the best plant, they are very adaptable, you can grow peas in all sorts of soil and climate.”

Professor Khan is a Research Professor at the UWA Institute of Agriculture, Faculty of Science, The University of Western Australia. In the past, he was an operational plant breeder concentrating on grain legumes for two decades with the WA Department of Agriculture and Food.

He initiated and produced the review in conjunction with scientists based in Australia, New Zealand, Canada and Spain.