The biodeterioration of sweet potato (
Ipomoea batatas
) was investigated at Port
Harcourt, south southern Nigeria.
Aspergillus niger
,
Fusarium oxysporum
,
Rhizopus stolonifer
,
Botryodiplodia theobroma
and
Penicillium
sp. were found to be associated with deteriorating sweet
potato tubers and used for inoculation of fresh sweet potato samples. The four prevalent isolates
(
Aspergillus niger,
Fusarium oxysporum Botryodiplodia theobroma and
Rhizopus stolonifer) were
each used to inoculate other sweet potato samples. Storage of samples in modified atmospheres and
the effects of inoculation on quality changes were also evaluated. Modified atmospheres created by
packing the samples inside a polythene bag of 18 µm thickness significantly maintained the quality
of the samples. Inoculation of samples with the four prevalent rot fungi significantly (p = 0.05)
increased crude protein, lipid and ash content. In contrast, there was a significant decrease in
carbohydrate and moisture content when compared with the controls. Modified atmosphere is
therefore recommended for control of sweet potato rots and extension of storage life.
