Resumen:
Government subsidies directed to particular groups of farmers, selected producers or selected geographical areas have their particular effect on those areas but really do not change tendencies on a complete sector. That is, sectorial programs have a systemic effect and particular programs have a non systemic effect affecting only products or regions but never the complete sector. The main variable that captures this effect is the per capita Gross National Product, which is an approximation to aggregated product over economical active population. It was found that the main support program to producers in Mexico has changed the structure in the use of production resources such as labour, capital, technology, land and water particularly among producers of medium and high incomes and with a moderate or low impact among those producers with low incomes.