Biology Reference
In-Depth Information
Figure 24:
Anabaenopsis
bloom in Bedetti Lake, Santo Tome, Santa Fe, Argentina. Picture courtesy Frederico Emiliani
(Universidad Nacional del Litoral), Mark Schneegurt (Wichita State University) and Cyanosite (www.cyanosite.bio.purdue.
edu).
Color image of this figure appears in the color plate section at the end of the topic.
Brazil and Patos Lagoon estuary of Rio Grande do Sul of southern Brazil developed blooms of toxic
M
.
aeruginosa
(Hirooka
et al
., 1999; Matthiensen
et al
., 2000). Certain picpoplanktonic cyanobacteria
from Caruaru reservoirs produced MCs in the concentrations ranging from 0.08 to 3.7 ng mg
-1
dry
weight suggesting that these organisms might have contributed to human poisoning in Caruaru for
long time (Domingos
et al
., 1998). In Chile also the lakes supported the growth of
Microcystis
spp.
producing various MCs (Campos
et al
., 1999; Neumann
et al
., 2000). The development of massive
blooms of
Pseudoanabaena
schmdlei
along with
M
.
aeruginosa
in the man-made reservoir of Northeast
Brazil resulted in the death of almost the whole fi sh population (Chellappa
et al
., 2000). Substantial
genetic diversity in
M
.
aeruginosa
was reported within and among lakes of Brazilian reservoirs
using phycocyanin intergeneric spacer and fl anking regions (
cpcBA
). Nine distinct genotypes were
collected from the four sites with the presence of as many as six genotypes from a single site and
one specifi c genotype existing at two sites. Moreover, a single genotype was represented along the
depth gradient repeatedly (Bittencourt-Oliveira
et al
., 2001). The occurrence of mixed cyanobacterial
blooms comprising of
C
.
raciborskii
,
M
.
panniformis
,
M
.
protocystis
,
M
.
novacekii
,
Aph
.
gracile
,
Aph
. c.f.
manguinii
,
Aph
. c.f.
issastschenkoi
(Fig. 2C) was recorded in Armanado Ribeiro Goncalves reservoir of
Brazil that serves as drinking water resource.
C
.
raciborskii
was predominantly represented during
rainy season with levels of STXs at 3.14
µg L
-1
. This was followed by the development of blooms
of species of
Microcystis
with MCs at 8.8 µg L
-1
in the transition period whereas in the dry period
co-dominance of
C
.
raciborskii
,
Microcystis
spp. and
Aphanizomenon
spp. was noted with low levels
of STXs (Costa
et al
., 2006). By targetting
mcyA
as marker gene, analysis of shoreline distribution of
