He is succeeded on the Education and Training Committee by Patrick Mitton.
BASIS chairman Chris Clarke paid tribute to Cobb's service and welcomed Mitton into the role, saying: "The whole organisation is deeply indebted to Andy for his tireless input both to the Committees he has chaired and the wealth of experience in education and governance that he brought to BASIS Board meetings. We wish Andy every success in the future and look forward to welcoming Patrick into his role.
"Patrick has a wealth of understanding on the needs of industry and the standards required for those selling and advising on crop protection, so he is the perfect person to take over from Andy as Chairman of the Education and Training Committee."
Mitton has had a long career in the crop protection industry, including positions at Bayer CropScience. He has also spent several years as a BASIS exam chairman. Since 2009 he has managed his own consultancy business AgriTopics Ltd, which offers advice on crop protection techniques to food industry stakeholders.
The Professional Matters Committee is under review by a group of BASIS Trustees and its future will be decided in November.