(2012) mention that the PCA is a multivariate statistical method that applies to
reduce the dimensionality of a data group and through the evaluation of the study
done by Ortega-Acosta (2015), the association between the physicochemical characteristics of the water quality of the Xochimilco water channels tested and the
functional attributes of the isolated endophytes from L. gibba plants from both
seasons; it suggests the functional participation of the phytobacteria in those water
channels according to the reported conditions, with the next final consideration for
each zone, as follows: Tourist zone was the most stable site, because it presented the
similar values of environmental and physicochemical conditions in both seasons,
followed by the Urban zone that showed considerable variations with some physicochemical parameters like sulfates, nitrates, total phosphorus and orthophosphate
contents, and pH. It is important to note that in this zone there was the minor number
of isolated endophytes with the only two phytobacteria that presented the
siderophore production trait. At least, Chinampera zone was considered the most
irregular zone, where all the environmental conditions tested presented contrasting
values; this zone also possesses the highest number of isolated endophytes with the
highest IAA production and ACC deaminase activity. The knowledge of the functional participation of the endophytes isolated in each zone would help to consider
this microorganism as an alternative to be employed as an assisted strategy of
phytoremediation of these water channels in the Xochimilco Lake.
7 Conclusions
Finally, with the particular study cases noted, the analysis of the functional diversity
of plant growth-promoting bacteria in terms of phenetic clustering and principal
component analysis showed differences among isolates, according to the zones
under study, and also the environmental variables in each zone determined the
diversity of the isolated organisms.
Acknowledgments The authors are grateful to the Research Project, SIP-20131494 and
SIP-20141314 of the Secretaría de Investigación y Posgrado del Instituto Politécnico Nacional,
Comisión de Operaciones y Fomento de Actividades Académicas (COFAA-IPN), EDI (Estímulo al
Desempeño de Investigadores-I.P.N.), and Sistema Nacional de Investigadores (SNI-CONACyT),
and the fellowships for its support.
References
Ahmad F, Ahmad I, Khan MS (2008) Screening of free-living rhizospheric bacteria for their
multiple plant growth promoting activities. Microbiol Res 163:173–181
Atlas RM, Bartha R (1993) Microbial ecology fundamentals and applications, 3rd edn. Benjamin
Cummings Publishing, New York
250
A. L. Guerrero-Zúñiga et al.
reduce the dimensionality of a data group and through the evaluation of the study
done by Ortega-Acosta (2015), the association between the physicochemical characteristics of the water quality of the Xochimilco water channels tested and the
functional attributes of the isolated endophytes from L. gibba plants from both
seasons; it suggests the functional participation of the phytobacteria in those water
channels according to the reported conditions, with the next final consideration for
each zone, as follows: Tourist zone was the most stable site, because it presented the
similar values of environmental and physicochemical conditions in both seasons,
followed by the Urban zone that showed considerable variations with some physicochemical parameters like sulfates, nitrates, total phosphorus and orthophosphate
contents, and pH. It is important to note that in this zone there was the minor number
of isolated endophytes with the only two phytobacteria that presented the
siderophore production trait. At least, Chinampera zone was considered the most
irregular zone, where all the environmental conditions tested presented contrasting
values; this zone also possesses the highest number of isolated endophytes with the
highest IAA production and ACC deaminase activity. The knowledge of the functional participation of the endophytes isolated in each zone would help to consider
this microorganism as an alternative to be employed as an assisted strategy of
phytoremediation of these water channels in the Xochimilco Lake.
7 Conclusions
Finally, with the particular study cases noted, the analysis of the functional diversity
of plant growth-promoting bacteria in terms of phenetic clustering and principal
component analysis showed differences among isolates, according to the zones
under study, and also the environmental variables in each zone determined the
diversity of the isolated organisms.
Acknowledgments The authors are grateful to the Research Project, SIP-20131494 and
SIP-20141314 of the Secretaría de Investigación y Posgrado del Instituto Politécnico Nacional,
Comisión de Operaciones y Fomento de Actividades Académicas (COFAA-IPN), EDI (Estímulo al
Desempeño de Investigadores-I.P.N.), and Sistema Nacional de Investigadores (SNI-CONACyT),
and the fellowships for its support.
References
Ahmad F, Ahmad I, Khan MS (2008) Screening of free-living rhizospheric bacteria for their
multiple plant growth promoting activities. Microbiol Res 163:173–181
Atlas RM, Bartha R (1993) Microbial ecology fundamentals and applications, 3rd edn. Benjamin
Cummings Publishing, New York
250
A. L. Guerrero-Zúñiga et al.