For example, in several countries people who live in the countryside actually are the main producers of wheat and also the meat that people need in their daily life.

producers 是名词 producer 的复数形式，由动词 produce（生产）加上后缀 -er（表示从事某种活动的人或物）构成，意思是"生产者、制造者"。在这里指从事农产品生产的人群。