Hi Joanne,

There are a number of biocontrol methods out there - the use of nematodes is one of the more common. It's about what you find acceptable; theese methods are not 100% effective but, if you're happy to trade off a few pests against intensive pesticide use it's a good option.

It's possible to use a combination of approaches - the IPM method that Stephanie mentioned. Generally that involves the use of barrier plants, refuges for beneficial insects, traps to monitor pest poulations , biocontrol and, if necessary, targeted pesticide use (the traps let you know ehere the problem is and you only spray that area). This si the approach that the main agricultural laboratories in the US, UK, Australia and Germany have been advocating for the last 15 - 20 years; much of our research has been aimed at proving to growers that the method does not result in serious losses and is as cheap as conventional pesticides - which is the really important thing.

To give you an idea, we have been advocating cooling stored grain as a pest control measure for many years. However, it was always more costly to install and run the aeration systems than to use conventional pesticide dusts. My colleagues spent years developing a system that only kicked in when there was a particular temperature difference between the grain temperature and the grain and, eventually, showed that aeration could be cheaper than pesticide admixture by about a tenth of a penny a tonne. This was enough and the large stores converted to aeration within about three years - profit margins are that tight.

Pete



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