Bob Knight, senior technical manager at Koppert UK, said biological controls often lend themselves more to soft fruit grown under tunnels.
Growers of apples, for example, found it tricky to use such controls for the treatment of foliar problems such as powdery mildew.
However, Knight will tell a British Independent Fruit Growers Association (BIFGA) conference that advances are swinging emphasis to top fruit. "Classical biological controls work against pests such as spider mite, but top fruit growers can also become involved," he said last week.
Enzicur, a curative spray, was due to be registered next year and treated mildew on fruit trees, he said. The product had been used successfully on salad crops in Holland.
John Haywood, technical director at PlantSyence, will tell the BIFGA technical day near Tunbridge Wells on 13 January of a new application for phosphorus and calcium.
PlantSyence has rolled out Calci-Phite PGA, which combines the two elements in one product, stabilised to avoid damaging reactions between the two.
The product was introduced to the UK last year and growers found it more convenient than conventional treatments, which required more applications, he said. "Growers used to applying seven or eight applications can be sceptical of switching to something requiring two. But applying calcium is such a bugbear and many people are desperate to get away from it. They are more willing to try something new."
Other speakers, including Horticultural Development Company technical manager Andrew Tinsley and East Malling Research's Professor Jerry Cross, will focus on health and safety in fruit growing, irrigation and mulching.
- For more details, contact Judy Perry on 01892 722080