1. Natural Resources
Institute, University of Greenwich, Central
Avenue, Chatham Maritime,
Kent, ME4 4TB, U.K.
2. Department of Agricultural Research Services, Lunyangwa Research Station, P.O.
Box 59, Mzuzu, Malawi
3. Department
of Chemistry, Mzuzu University, P/Bag 201,
Luwinga Mzuzu 2, Mzuzu,
Malawi
4. Jodrell Laboratory, Royal Botanic Gardens, Kew, Richmond, Surrey, TW9 3DS,
U.K.