5 research outputs found
Effect of glyphosate toxicity on growth, pigment and alkaline phosphatase activity in cyanobacterium <i>Anabaena doliolum: </i>A role of inorganic phosphate in glyphosate tolerance
208-213Response of glyphosate toxicity on photoautotrophic
cyanobacterium A. doliolum and its mutant strain was investigated.
Chlorophyll a content of both the wild type and mutant strain in the
presence of glyphosate (N-phosphonomethyl glycine) initially showed an increasing
trend when supplemented with Pi and a declining tendency under the Pi-starved condition.
The results suggested that both the wild type and mutant strains were more sensitive
to glyphosate in the absence of phosphate. Alkaline phosphatase activity of
wild type strain in the presence of Pi, enhanced in response to addition of glyphosate
(40 μg/ml), but the activity remained unaltered by addition of glyphosate in
the Pi-starved cells, whereas the alkaline phosphatase activity in the mutant strain
under both Pi-starved as well as unstarved conditions was stimulated
(approximately 5.4 and 3.1-fold, respectively) by addition of glyphosate. The
results on alkaline phosphatise activity indicated a glyphosate-induced depletion
in the phosphate content of the cells, particularly in the mutant strain, as evident
from the stimulated activity of alkaline phosphatase. It is suggested that enzyme
activity in the Pi-starved wild type cells may not be influenced any further by
glyphosate, as cellular phosphate reserve might not be available for further depletion