PERTANIKA JOURNAL OF TROPICAL AGRICULTURAL SCIENCE

A pot experiment was conducted to study the effectiveness of two arbuscular mycorrhiza ( A M ) species in enhancing growth o f cocoa seedlings. Cocoa seedlings o f hybrid U I T I x Na32 inoculated with Glomus mosseae and Scutellospora calospora either as a single inoculum or as a mixed inoculum and an uninoculated control were grown in 2 kg sterilized Tai Tak series soil. The experiment was a single factor experiment arranged in a completely randomized design, with type o f inoculum as a factor with four replications. O f the four treatments used, plants inoculated with mixed inoculum Glomus mosseae and Scutellospora calospora gave more pronounced and significant vegetative growth and higher percentage o f root colonization than the other treatments. Maximum plant height and total leaf area o f 43.7 cm and 1819.2 cm2 respectively were obtained from seedlings inoculated with mixed inoculum compared to seedlings given either G. mosseae (37.9 cm dan 1007.2 cm2) , or S. calospora (32.3 cm and 1316 cm2) and control (28.5 cm and 736.7 cm2) . The highest percentage o f root colonization (7 2% ) was also recorded from seedlings inoculated with mixed inoculum followed by those given S. calospora (5 4% ) and single inoculum G. mosseae (4 3% ).