Advisor(s)
Abstract(s)
Variation on bacterial communities living in the phyllosphere as epiphytes and endophytes has been attributed to plant host
effects. However, there is contradictory or inconclusive evidence regarding the effect of plant genetics (below the species’ level)
and of plant tissue type on phyllosphere bacterial community assembly, in particular when epiphytes and endophytes are
considered simultaneously. Here, both surface and internal bacterial communities of two olive (Olea europaea) cultivars were
evaluated in twigs and leaves by molecular identification of cultivable isolates, with an attempt to answer these questions.
Overall, Proteobacteria, Actinobacteria and Firmicutes were the dominant phyla, being epiphytes more diverse and abundant
than endophytes. Host genotype (at cultivar level) had a structuring effect on the composition of bacterial communities and, in a
similar way, for both epiphytes and endophytes. Plant organ (leaf vs. twig) control of the bacterial communities was less evident
when compared with plant genotype and with a greater influence on epiphytic than on endophytic community structure. Each
olive genotype/plant organ was apparently selective towards specific bacterial operational taxonomic units (OTUs), which may
lead to specific feedbacks on fitness of plant genotypes. Bacterial recruitment was observed to happen mainly within epiphytes
than in endophytes and in leaves as comparedwith twigs. Such host specificity suggested that the benefits derived fromthe plant–
bacteria interaction should be considered at genetic levels below the species.
Description
Keywords
Diversity Host specificity Microbiota Olea europaea L Organ specificity
Citation
Mina, Diogo; Pereira, José Alberto; Lino-Neto, Teresa; Baptista, Paula (2020). Epiphytic and endophytic bacteria on olive tree phyllosphere: exploring tissue and cultivar effect. Microbial Ecology. ISSN 0095-3628. p. 1-13