Which of the following is NOT a function of marketing boards in Nigeria?

In Nigeria, marketing boards were established to regulate and promote agricultural products. Their primary functions include activities like grading farm produce to ensure quality standards and marketing farm produce by finding markets where these products can be sold. They are also responsible for fixing prices for farm produce to stabilize farmers' incomes and protect them from market fluctuations.

However, one activity that marketing boards do not typically perform is the importation of farm produce. Marketing boards are mainly concerned with the domestic production and distribution of local agricultural products, whereas the importation would fall under international trade domains and different regulatory agencies. Thus, the importation of farm produce is not a usual function of marketing boards in Nigeria.