Detection of fungi in brazilwood seeds (Caesalpinia echinata Lam.) collected during seed formation and dispersion

Brazilwood, also known as Pau-Brasil or Pernambuco, (Caesalpinia echinata Lam. Syn. Guilandina echinata (Lam.) Spreng.) is a Brazilian forest tree species which has important commercial uses but is at present listed as an endangered species by the International Union for Conservation of Nature (IUCN). Removal of brazilwood from the IUCN endangered species list is important roe its continued comercial utilization. Tropical forest species are propagated by several mechanisms but seeds are one of the main processes, which means that the health and physiological quality of the seeds of such species are important factors in their propagation. Our objective was to verify the incidence of fungi during the formation and dispersion of C. Echinata seeds because there are few accounts regarding the incidence of fungi in C. Echinata seeds and the reports that do exist do not clarify the point in seed formation when fungal infection occurs. We used the health-test to analyze seeds collected at different seed formation stages (post-anthesis and dehiscence). The main fungi detected being Cladosporium cladosporioides, Pestalotiopsis maculans and Epicoccum sp, with a lower incidence of Aspergillus sp, Fusarium sp., Nigrospora sp. and Penicillium sp. We found that C. cladosporioides and P .maculans were present in seeds since the beginning of seed formation, at the 40 days post-anthesis collection, and that the incidence of fungi increased with time reaching 100% in seeds with one and two days of dehiscence. We detected Fusarium sp. in seeds collected after dehiscence and the incidence increased while the seeds remained in contact with soil. (AU)