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Volume 7, Issue 6 (Suppl) J Bacteriol Parasito
ISSN: 2155-9597 JBP, an open access journal Microbiology 2016
November 28-29, 2016
November 28-29, 2016 Valencia, Spain
7th World Congress on
Microbiology
J Bacteriol Parasitol 2016, 7:6 (Suppl)
Aproposal for the unification of two strains of cyanobacteria genus Nostoc to the same species
Bahareh Nowruzi1, Ramezan-Ali Khavari-Nejad1, 2, Taher Nejadsattari1, Karina Sivonen3 and David P Fewer3
1Islamic Azad University, Iran
2Kharazmi University, Iran
3University of Helsinki, Finland
Studies of cyanobacteria are important to the global scientific community because of their ecological and applied importance.
Amongst the different cyanobacterial orders, the Nostocales and Stigonematales orders are especially important as they fix
atmospheric nitrogen and thus contribute to the fertility of agricultural soils worldwide. However, in spite of their ecological
importance and environmental concerns, their identification and taxonomy is still problematic and confusing, often being based
on current morphological and physiological studies, which generates confusing classification systems based on plastic characters
that vary with the environmental and cultural conditions. The present research aimed to investigate through a polyphasic approach,
the differences in morphological and genotypic features of two cyanobacteria strains isolated from paddy fields of Iran, belonging
to the family Nostocaceae (subsection IV. I). Based on the description of the morphology provided by Desikachary (1959), the two
strains were identified as Nostoc ellipsosporum and Nostoc muscorum. Challenges arose when the two Nostoc strains could not be
discriminated by 16S rRNA and ITS genes sequencing. The results of sequencing of the cloned bacterial 16S rRNA fragment strongly
indicated that the current morphological classification of the two Nostoc species is invalid. Moreover, phylogenetic study of these
two Nostoc strains has demonstrated that genetic relationships are in conflict with the morphological classification. Besides, after
doing DNA-DNA re-association experiments, we concluded that the two Nostoc strains investigated might possibly be united into
one species.
Plant parasitic weed endophytic bacteria triangle
Lilach Iasur Kruh1, 2, Jacline Abu-Nassar1, Shiri Freilich1 and Radi Aly1
1Agricultural Research Organization, Israel
2ORT Braude College, Israel
Phelipanche and Orobanche species (broomrapes) are holoparasitic plants that connect to the vascular systems of their hosts,
allowing the transfer of various substances including a possible exchange of endophytic bacteria that inhabit the internal tissues
of both plants. To shed light on the microbial aspects of the parasitic interaction between Phelipanche aegyptiaca and its host, tomato,
we characterized the endophytic composition in both plants before and after attachment using mass sequencing analysis. Endophyte
communities of the parasitic weed were significantly different from that of the non-parasitized tomato root but no significant
differences were observed between the parasite and its host, parasitized tomato root, suggesting bacterial exchange between these
two plants. In addition to molecular analysis, isolation of endophytic bacteria from the parasitic weed-host plant system enabled
to examine whether these isolates can affect the dynamics of host-parasite interaction. Endophytic bacteria isolates were examined
for their ability to secrete substances that may affect the dynamics of this system and indeed, a few isolates inhibit the growth of the
parasitic weed. The current study focuses on the bacterial aspect of host-parasite interaction and highlights the potential of exploiting
alternative environmentally friendly approaches for parasitic weed control.