UPDATE 3-Argentine government backers rally against strike

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By Kevin Gray

BUENOS AIRES, April 1 (Reuters) - Argentine President Cristina Fernandez, mired in a political crisis after 20 days of a farm strike that has caused food shortages, sought to show her resolve on Tuesday with a huge pro-government rally.

Farmers irate over higher soy export taxes have held back goods from market since March 13, making fresh food scarce in the capital and freezing grains exports from Argentina, a top world supplier of soy, corn, wheat and beef.

Fernandez called on farmers to clear roadblocks from highways as she addressed tens of thousands of cheering allies from unions and community and human rights groups.

"Don't do more harm to the people, lift the roadblocks so Argentines can get food," she said.

Farm leaders say they will decide on Wednesday whether to continue their protest at highways all over the country.

Last week Fernandez faced her first major anti-government demonstration, when thousands of middle-class Argentines banged pots and pans in city streets in support of the farmers.

Political commentator James Neilson said Tuesday's rally was intended to show that the government had not been weakened and was backed by public opinion in taking a tough stance against the farm protest.