Tanzania will this year begin its first field trials of genetically modified (GM) crops. The first plants to be tested will be cotton modified to resist attack by insect pests, including a caterpillar known as red bollworm that feeds on cotton and causes bollworm disease. The plans were announced by Wilfred Ngirwa, permanent secretary for the Ministry of Agriculture and Food Security, at an international workshop on GM crops held in Arusha on 7 February.