Poster: Biology & Disease Mgmt: Postharvest Pathology & Mycotoxins
Profile of Aspergilli in fields under continuous maize and groundnut cultivation and aflatoxin contamination along the crop value chains in Mozambique
J. AUGUSTO (1), J. Atehnkeng (2), J. Akello (3), P. Cotty (4), R. Bandyopadhyay (5) (1) Intl Inst of Tropical Agriculture, Mozambique; (2) International Institute of Tropical Agriculture, Malawi; (3) International Institute of Tropical Agriculture, Zambia
Aflatoxins are routinely reported in maize and groundnut in Mozambique, but the profile of aflatoxigenic fungal isolates in the fields continuously cultivated with maize or groundnut and the extent of aflatoxin accumulation along the maize and groundnut value chains are unknown. Georeferenced soil samples were taken from 250 farmers’ fields at harvest in 2013 and 2014 in different agro-ecological zones (AEZ) to determine Aspergilli profile. The fields had been under continuous maize or groundnut cultivation from two to five years. Also, aflatoxin content was measured in 300 maize and groundnut samples collected along the crops’ value chains. Inoculum density of Aspergilli was high (>2,000 CFU/g) in fields under extended (³3 years) continuous cultivation, and low-medium (0-2,000 CFU/g) either in fields with <3 years of consecutive cultivation, or at high altitude AEZ (>1,000m), irrespective of crop. Aspergillus flavus S (34%) and L (31%) morphotypes were most frequently isolated from fields under intensive cultivation (³3 years), but L morphotype was predominant (>50%) in fields with <3 years of continuous cultivation, irrespective of crop or AEZ. Aflatoxin content was high in groundnut leftovers used for human consumption after sorting (max. 3,874 ppb), groundnut from storage (max. 1,777 ppb) and groundnut sold at marketplaces (max. 720 ppb). These results suggest that targeted aflatoxin management practices may be required along the crop value chains in Mozambique.