"Farmers have indicated to us that there is a shortage of farm labour, especially for seasonal work, " the ministry said in a statement, quoted by the AFP news agency.

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Put simply, this is the point at which a developing country stops being able to achieve rapid growth relatively easily, by simply taking rural workers doing unproductive farm labour and putting them to work in factories and cities instead.

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Then along comes the tractor, the mechanical baler, the first milking machines, and the need for labour on the farm falls precipitately.

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Poor countries need to sell their labour-intensive and farm products to rich ones.

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Farm workers were once compensated for their labour in wine, with disastrous health consequences.

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Labour productivity continues to grow, with non-farm output per hour increasing by 1.1% at an annual rate in the second quarter.

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Mr Dawson, its choice for October 2000, catalogued a life of continuous manual labour, starting at the age of four as a farm hand.

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South Africa has increased the basic daily wage of farm workers by 52% following a violent strike in the wine-producing Western Cape region, the labour minister has said.

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Intriguingly, the voucher debate has pitched civil-rights-era black leaders and teachers' unions, who oppose the idea, against supporters ranging from the conservative governor of Florida, Jeb Bush, to the leftist head of the Milwaukee school board, John Gardner, a labour organiser who once led a campaign to support Cesar Chavez, the founder of the migrant farm-workers' union.

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