7 March 1997

Resistant varieties could avoid herbicide damage

By Andrew Blake

IN-BRED herbicide resistance should help sugar beet growers avoid subclinical damage from weed-killers and boost yields, according to Monsantos Colin Merritt.

But commercial glyphosate-resistant varieties are unlikely to be available until 2000-2001. Weed control in beet was generally good, Mr Merritt told ADASs Peterbor-ough root conference. But achiev-ing it had several down-sides, not least the risk of harming the crop. Trials applying three times the expected commercial application rate of glyphosate to so-called Roundup-Ready varieties produced from naturally occurring genes were particularly reassuring, he said. "Crop safety is outstanding."

Compared with conventional programmes, which could check crops, there was often a yield increase, sometimes up to 7%. "It could take plant breeders 20 years to achieve that." Mr Merritt acknowledged such biotech developments disturbed some sectors of the public. But with variety trials starting only this year, there was a useful period of grace to allow the systems benefits to be appreciated and fears allayed, he maintained.

"Communication and education is the key to progress." Much behind-the-scenes discussion with the NFU, British Sugar and others was under way to try to counter scare stories being put out by some organisations, he said.

One big advantage of the new approach was that it removed the need for insurance treatments. "You only spray when you need to." &#42

Residual insurance herbicide treatments could become obsolete once new resistant beet varieties, here spot-sprayed with glyphosate, come on stream.


BEET WEED FUTURE


&#8226 Control generally good, but crop damage can occur.

&#8226 Herbicide tolerant crops overcome that risk.

&#8226 7% yield lift possible.

&#8226 Years of trials still to do.