Sss. Sarma et al., Population growth of Euchlanis dilatata (Rotifera): Combined effects of methyl parathion and food (Chlorella vulgaris), J ENVIR S B, 36(1), 2001, pp. 43-54
Citations number
34
Categorie Soggetti
Environment/Ecology
Journal title
JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH PART B-PESTICIDES FOOD CONTAMINANTS AND AGRICULTURAL WASTES
In the present work, the combined impact of four concentrations (0, 0.0625,
0.125, and 0.25 mg/L) of methyl parathion and three densities (0.5 x 10(6)
, 1.0 x 10(6), and 2.0 x 10(6) cells/mL) of the green alga Chlorella vulgar
is on the population growth of Euchlanis dilatata was studied. In general,
regardless of the food level, an increase in the concentration of methyl pa
rathion resulted in a significant reduction of the maximal population densi
ty and rate of population increase. The population growth rate in the contr
ols ranged from 0.248 to 0.298; rates were lower in the presence of the pes
ticide. At any toxicant concentration, rotifers fed higher algal density sh
owed significantly higher population growth compared with those at lower fo
od levels. An interaction between toxicant and food level was evident on th
e population growth of E. dilatata. Results have been discussed in light of
the protective role of algal density on the toxic effects of insecticides
on rotifers and the differences in susceptibility to toxicants between plan
ktonic and littoral rotifers.