|
CSIRO Media Release |
|||
| Mr Julian Cribb | (02) 6276-6244 | |||
| Mobile | (0418) 639-245 | |||
| Fax | (02) 6276-6821 | |||
|
|
||||
30 December 1998 |
Ref 98/298 |
|
|
The most important livestock on the 21st century Australian farm may well be living underground, say two leading CSIRO soil microbiologists.
Agriculture is on the brink of a second revolution, this time involving the vast range of micro-organisms which inhabit the soil, and influence the growth of crops, pasture and larger animals such as cattle and sheep.
Dr Maarten Ryder and Mr David Roget say these micro-organisms are already intimately involved in the productivity of our farming systems but the potential for greater understanding and utilisation of this resource is enormous.
Their prediction is already coming true. Researchers at CSIRO Land and Water have found that an Australian soil microbe called Trichoderma helps to control take-all and rhizoctonia, two of the most devastating cereal root diseases worldwide.
"These diseases cost Australian, Chinese and other farmers hundreds of millions of dollars in lost grain every year," says Dr Ryder.
"But we've found that this naturally-occurring soil micro-organism attacks the disease-causing fungus with antibiotics which slow or arrest its growth.
"It was found more than 10 years ago in a Western Australian soil by Dr Andrew Simon of CSIRO and it has worked remarkably well in two countries. In China they got an average 10 per cent yield improvement, and in Australia we obtained an 8 per cent boost."
CSIRO and Chinese research partners consider that the Trichoderma can be used as a crop seed treatment, using fermentation and formulation techniques developed by the Chinese reseachers.
In a separate development, joint research through the CRC for Soil and Land Management has resulted in special DNA probes to tell farmers how severely their paddocks are affected by the take-all fungus, and what crop yield penalty they can expect to suffer.
"This technology is a world first that provides rapid and accurate information to aid in farm management decisions for the adoption of the most profitable cropping strategy," says Mr Roget.
The researchers have also established that soils vary in their ability to naturally suppress crop diseases and that the level of disease suppression can be increased with the right management through manipulation of the soil micro-organisms already present in the soil. Having soils with a high level of disease suppression allows much greater flexibility in the farming system.
"The soil is alive with microorganisms. There are more than 100 million in a single gram," Mr Roget explains.
Dr Ryder and Mr Roget believe these soil bugs represent the most important yet neglected aspect of modern agriculture. We have attended to the obvious needs of plants and animals, the chemical and physical properties of soil and water - but we are barely starting to explore the vastly rich and complex ecosystem in the top 20cm of dirt.
"We have hardly begun to experiment with manipulating populations of soil organisms to achieve the best results in our crops and pastures," Mr Roget explains.
Worldwide, many soil-borne diseases cut farmers' yields by a half or more. The answer to some of these could lie in developing a range of benign soil microbes which fight the crop-destroyers, Dr Ryder believes.
Besides the plant-protector bugs, there are other microbes which make the soil richer and which unlock vital nutrients so plants can use them. Still other types of microbes produce plant hormones which stimulate crop growth.
In future, Dr Ryder and Mr Roget predict, part of farming will involve managing this invisible ecosystem beneath the soil, finding ways to encourage the microbes which benefit crops or pastures and suppress those which harm them.
"We are already experimenting with the addition of different mixtures of microbes to see if we can get better plant growth or disease suppression, and it is very clear that we can," Dr Ryder says.
Sometimes the same bug has more than one effect. One of Australia's best biological agents for controlling take-all disease in wheat, for example, is equally effective at preventing root rot in cotton in China.
But the big payoff, the researchers believe, will come from using the synergy of a number of microbes, all performing different tasks to protect the plant and help it grow.
Developing ways to encourage these benign microbes could become an Australian farming specialty, they think.
"Australia has such as wide array of climates and environments, all with their own unique soil organisms. Among these, there are endless opportunities to solve problems that limit food production, not just here, but round the world."
Finding a way to reduce the toll taken by rhizoctonia and take-all of the world's grain harvest could make a huge difference to the food supply for millions of people.
More information:
Dr Maarten Ryder, CSIRO Land & Water 08 8271 1812 or
015 978 607 mobile
Mr David Roget, CSIRO Land & Water 08 8303 8528
Ms Margaret Bryant, CSIRO Land & Water 08 9330 3101
(Australia's largest scientific research organisation)
[CSIRO Search] [What's New] [Help] [Newsline] [CSIRO Home Page]
©Copyright 1998, CSIRO Australia
Use of this web site and information available from it is subject to our
Legal Notice and Disclaimer