September 12, 2003
Poor farmers
in developing countries could soon be using a range of
'biofumigant' plants to help increase tropical vegetable yields.
CSIRO is part of a research
team from Australia and the Philippines which has found that
brassica species such as radish, mustard or broccoli can be used
to help reduce yield losses from Bacterial Wilt - the major
pathogen of vegetables in tropical farming.
"Brassicas
contain compounds that suppress pests and pathogens, principally
isothiocyanates (ITCs)," says CSIRO Plant Industry researcher,
Dr John Kirkegaard.
"When ITCs are
released by manuring, soil-borne pests and pathogens are
suppressed and yields of solanaceous vegetables such as
potatoes, tomatoes and eggplants can be increased by up to 40
per cent. The effect is known as 'biofumigation'."
The project
has already evaluated brassica species and management techniques
with the aim of maximising the biofumigant effect. Current field
trials in the Philippines and in North Queensland are examining
ways of making biofumigation practical and effective for
developing countries.
Using
brassicas to manage soil-borne pests is not new - there are many
previous reports of disease suppression - but new insights and
techniques to measure the processes involved in the release of
chemicals in soil has provided opportunities to enhance the
reliability of the effect.
"The project
builds on that research and is making it practical for
small-scale farmers around the world," Dr Kirkegaard says.
"There are
economic and social benefits for small-scale farmers, as
improved crop yields lead to increased incomes. There are also a
range of environmental and health benefits, as a result of
reduced reliance on toxic fumigants and synthetic pesticides.
"The next
stage of the project seeks farmer involvement to integrate
biofumigation into the cropping system, using farming networks
throughout South-East Asia and the Pacific."
The team
includes researchers from CSIRO Plant Industry, the Queensland
Department of Primary Industry and the Philippines National Crop
Protection Centre. The project is funded by the Australian
Centre for International Agricultural Research (ACIAR). |