Pesticide use eases land pressures
Pesticide use eases land pressures
FOOD production to meet global demand requires 15m sq km of farmland, it has been calculated. If no pesticides were used the area would need to be doubled, requiring the cultivation of a further area equivalent to the whole of South America.
That is the simple answer to the question why use pesticides? IACR Rothamsted scientist Ken Evans told the recent Sustainable Potato conference organised by Aventis in Barcelona.
If no fertilisers were allowed, a further 25m sq km would be needed. "But we just dont have those sorts of areas available. Pesticides protect 15m sq km from going under the plough."
Dr Evans acknowledged the arguments put forward that organic control would be better.
But work by Texas University shows the yield penalty of key crops from going organic can range from 37% to 78%. That would require up to four times more land to produce the same output.
Dr Evans went on to explain how a 20m grid for potato cyst nematode sampling could help growers patch treat crops with relatively little risk of undetected PCN patches knocking crop output.
However, growers and agronomists at the event remained concerned about the implications for population build-up over the longer term. *