Mycorrhizal and endophytic richness and colonization in Cedrela odorata L., in agroforestry systems and secondary forest from southeastern Costa Rica

Abstract

The roots of different forest species showmixed colonization by arbuscular mycorrhizal fungi(AMF) and dark septate fungi (DSE). In temper-ate ecosystems, AMF colonization and communitystructure change according to plantation age, whilecolonization by DSE is apparently unaffected. How-ever, in tropical ecosystems, little has been docu-mented on the possible changes caused by planta-tion age on mycorrhizal fungal communities. Weanalyzed AMF and DSE colonization and describedthe glomerospore community structure associatedwith three agroforestry systems of different Cedrelaodorata plantation ages (8, 13 and 17 years), in addi-tion to a secondary forest, during the dry season in southeastern Costa Rica. We detected statistical dif-ferences in total colonization in the agroforestry sys-tems with respect to the secondary forest (P < 0.05).Among the agroforestry systems, total colonizationwas higher in 8-year-old trees and DSE were onlydetected in agroforestry systems with higher coloni-zation in 8-year-old trees. The abundance and rich-ness of glomerospores were higher in the agroforestrysystems than in the secondary forest, with greaterrichness in younger plantations. We isolated 39 mor -phospecies, 27 from the plantations and 17 from thesecondary forest, with a greater representativeness ofAcaulospora and Glomus. We also provide four new AMF reports for Costa Rica (Acaulospora laevis, A.excavata, A. spinosissima, and A. bireticulata).