The effect of drought and a poor payment system by the GMB, is said to be the reason for the drop of volumes of maize delivered to the GMB this year, the board said.
GMB has outlined a budget of US$80mn to the Zimbabwean government for the 2013-14 marketing season for maize intake purchases and resources for reserving grain, which include tarpaulins and gum poles.
Last season, GMB recorded that it had received 81,190 tonnes of maize from farmers.
Grain Millers Association president, Tafadzwa Musarara, said millers had already transported 5,000 tonnes of maize from South Africa and Zambia, but had stopped importing to help local farmers.
Most purchasers of maize are paying cash on delivery while others pay within seven days, millers and stockfeed manufacturers being the main buyers, GMB revealed.