3 research outputs found
Response of the Nonbiting Midge <i>Chironomus riparius</i> to Multigeneration Toxicant Exposure
The ability of the nonbiting midge <i>Chironomus riparius</i> to withstand long-term toxicant exposure has been attributed to
genetic adaptation. Recently, however, evidence has arisen that supports
phenotypic plasticity. Therefore, the present study aimed to investigate
if <i>Chironomus riparius</i> indeed copes with prolonged
toxicant exposure through phenotypic plasticity. To this purpose,
we performed a multigeneration experiment in which we exposed <i>C. riparius</i> laboratory cultures for nine consecutive generations
to two exposure scenarios of, respectively, copper, cadmium, and tributyltin.
Total emergence and mean emergence time were monitored each generation,
while the sensitivity of the cultures was assessed at least every
third generation using acute toxicity tests. We observed that the
sublethally exposed cultures were hardly affected, while the cultures
that were exposed to substantially higher toxicant concentrations
after the sixth generation were severely affected in the eighth generation
followed by signs of recovery. A marginal lowered sensitivity was
only observed for the highly exposed cadmium culture, but this was
lost again within one generation. We conclude that <i>C. riparius</i> can indeed withstand long-term sublethal toxicant exposure through
phenotypic plasticity without genetic adaption
Response of the Nonbiting Midge <i>Chironomus riparius</i> to Multigeneration Toxicant Exposure
The ability of the nonbiting midge <i>Chironomus riparius</i> to withstand long-term toxicant exposure has been attributed to
genetic adaptation. Recently, however, evidence has arisen that supports
phenotypic plasticity. Therefore, the present study aimed to investigate
if <i>Chironomus riparius</i> indeed copes with prolonged
toxicant exposure through phenotypic plasticity. To this purpose,
we performed a multigeneration experiment in which we exposed <i>C. riparius</i> laboratory cultures for nine consecutive generations
to two exposure scenarios of, respectively, copper, cadmium, and tributyltin.
Total emergence and mean emergence time were monitored each generation,
while the sensitivity of the cultures was assessed at least every
third generation using acute toxicity tests. We observed that the
sublethally exposed cultures were hardly affected, while the cultures
that were exposed to substantially higher toxicant concentrations
after the sixth generation were severely affected in the eighth generation
followed by signs of recovery. A marginal lowered sensitivity was
only observed for the highly exposed cadmium culture, but this was
lost again within one generation. We conclude that <i>C. riparius</i> can indeed withstand long-term sublethal toxicant exposure through
phenotypic plasticity without genetic adaption
Response of the Nonbiting Midge <i>Chironomus riparius</i> to Multigeneration Toxicant Exposure
The ability of the nonbiting midge <i>Chironomus riparius</i> to withstand long-term toxicant exposure has been attributed to
genetic adaptation. Recently, however, evidence has arisen that supports
phenotypic plasticity. Therefore, the present study aimed to investigate
if <i>Chironomus riparius</i> indeed copes with prolonged
toxicant exposure through phenotypic plasticity. To this purpose,
we performed a multigeneration experiment in which we exposed <i>C. riparius</i> laboratory cultures for nine consecutive generations
to two exposure scenarios of, respectively, copper, cadmium, and tributyltin.
Total emergence and mean emergence time were monitored each generation,
while the sensitivity of the cultures was assessed at least every
third generation using acute toxicity tests. We observed that the
sublethally exposed cultures were hardly affected, while the cultures
that were exposed to substantially higher toxicant concentrations
after the sixth generation were severely affected in the eighth generation
followed by signs of recovery. A marginal lowered sensitivity was
only observed for the highly exposed cadmium culture, but this was
lost again within one generation. We conclude that <i>C. riparius</i> can indeed withstand long-term sublethal toxicant exposure through
phenotypic plasticity without genetic adaption