Step 1 - The old relationship of patronage:
Earlier, agricultural labourers, often called halpatis or begar workers, were tied to a particular landlord in a long-term, hereditary bond. The relationship was unequal but personal.
Step 2 - What patronage meant in practice:
The landlord was expected to look after the worker's basic needs. He provided food, shelter, loans in times of crisis and help during illness or marriage. In return the worker gave his labour and his loyalty for life.
Step 3 - The change after the Green Revolution:
With commercialisation of agriculture, the spread of machines and the growth of a market economy, this bond broke down. Labour began to be hired on a daily wage or on contract, only when needed.
Step 4 - The new relationship of exploitation:
The relationship became purely economic and impersonal. The landlord no longer had any obligation towards the worker beyond paying the wage for the day.
Step 5 - Its consequences for workers:
Workers gained a measure of freedom, since they were no longer bonded, but they lost all security. They now face seasonal unemployment, low wages and the need to migrate in search of work.
This shift from a caring but unequal bond to a purely market relationship is what Breman called the move 'from patronage to exploitation'.