Epiphytes colonized plant surfaces to form dense
biofilm (Figs. 4 and 5). CRA method used for testing biofilm
formation revealed moderate biofilm formation for some
epiphytes, with the formation of pink colonies (SFig. 1).
Out of twenty characterized culturable epiphytic bacteria,
thirteen isolates showed the ability for biofilm formation
(Table 1). Micrographical and molecular approach recovered
B.thuringiensis as the most prevalent epiphyte capable
of forming biofilm on plant surfaces which has also been
reported as a biocontrol agent [28]. Leaf and root microbiota
are reported to provide plant growth-promoting and
protection against pathogens [29]. Microbial cells within
biofilms have better chances of adaptation and survival due
to the protection fromthe biofilmmatrix [30]. Considerable
evidence has indicated bacteria to modify their environment,
such as by increasing nutrient concentrations to
enhance their colonization on plant surfaces [2,31]. This
habitat modification may be augmented by cooperative
interactions among bacteria which may occur among both
homogeneous and heterogeneous populations. Bacterial
interaction is mediated by quorum-sensing in which bacteria
sense the presence of neighbouring cells by detecting an
increase in concentration of constitutively produced extracellular
molecules, N-acyl homoserine lactones (HSL) [32]