3.1. Molecular identification of A. flavus and A. parasiticus
Molecular sizes of the DNA of fungal species were estimated by
the fluorescence intensity and comparison of the distance travelled
with that of the molecular weight of marker standard as measured
using gel electrophoresis and shown in Fig. 2. However, the data
indicated that the DNA fragment in lane IV compared to lane III has
relatively distinct molecular sizes of 742 bp and 737 bp. This
distinct size difference, in relation to their Restriction Fragment
Length Polymorphism (RFLP) according to Somashekar et al. (2004)
studies, may be suggested to give reasons for the AF production
capacity of A. parasiticus against that of A. flavus (Iheanacho, 2012;
Iheanacho et al., 2014), with respect to the AF types they both
produce.
Identification of fungi by molecular means is considered the
most reliable over conventional method. Though it is expensive,
labour and time intensive, it has become the most common tool for
rapid identification A. flavus, A. parasiticus and other types of
environmental fungi. The species of fungi identified are not
morphologically and molecularly similar; however, they can be
identified further as a variety of closely related species. Suggestions
made by Martinez-Culebras and Ramon (2007), Varga et al. (2011)
and El khoury et al. (2011) on phylogenetic analysis using ITS and by
Msiska (2008) and using -tubulin genes can be adopted in
developing a differential relationship between closely related