The current bumblebee decline leads to inbreeding in populations that fosters a loss of allelic diversity and diploid male production. As diploid males are viable and their offspring are sterile, bumblebee populations...The current bumblebee decline leads to inbreeding in populations that fosters a loss of allelic diversity and diploid male production. As diploid males are viable and their offspring are sterile, bumblebee populations can quickly fall in a vortex of extinction. In this article, we investigate for the first time a potential premating mechanism through a major chemical reproductive trait （male cephalic labial gland secretions） that could prevent monandrous virgin queens from mating with diploid males. We focus our study on the cephalic labial gland secretions of diploid and haploid males ofBombus terrestris （L.）. Contrary to initial expectations, our results do not show any significant differentiation of cephalic labial gland secretions between diploid and haploid specimens. Queens seem therefore to be unable to avoid mating with diploid males based on their compositions of cephalic labial gland secretions. This suggests that the vortex of extinction of diploid males could not be stopped through premating avoidance based on the cephalic labial gland secretions but other mechanisms could avoid mating between diploid males and queens.展开更多
Naturally-occurring and artificially-induced polyploids have been documented in various fish species but to date no comparison has been reported of the impacts of ploidy on fish biomarker responses to organic pollutan...Naturally-occurring and artificially-induced polyploids have been documented in various fish species but to date no comparison has been reported of the impacts of ploidy on fish biomarker responses to organic pollutants.This study describes effects of ploidy,gender,and dose on biliary fluorescent aromatic compound（FAC） concentrations,hepatic ethoxyresorufin-O-deethylase（EROD） and glutathione S-transferase（GST） activities in one of the most commonly cultured warm-water species,the African catfish Clarias gariepinus.Recently matured male and female diploid and triploid fish were intraperitoneally（i.p.）injected with 0,5 or 25 mg/kg benzo[a]pyrene（BaP） and liver and gallbladder were sampled48 hr later.No significant differences were found between ploidies in bile concentrations of7,8 dihydrodiolbenzo[a]pyrene（7,8D BaP）,1-hydroxybenzo[a]pyrene（1-OH BaP） or3-hydroxybenzo[a]pyrene（3-OH BaP）.However,concentrations of the biliary FACs did differ between males and females at different dose of injection with generally higher concentrations in females at the low dose of BaP and higher concentrations in males at the higher BaP concentration.Hepatic EROD activity did not exhibit gender-dependent difference,whereas it was significantly higher in triploids than diploids.GST activities were not significantly influenced by any of the tested factors.This work advanced our understanding of the role of ploidy,gender,and dose in biotransformation of pollutants in fish.展开更多
文摘The current bumblebee decline leads to inbreeding in populations that fosters a loss of allelic diversity and diploid male production. As diploid males are viable and their offspring are sterile, bumblebee populations can quickly fall in a vortex of extinction. In this article, we investigate for the first time a potential premating mechanism through a major chemical reproductive trait （male cephalic labial gland secretions） that could prevent monandrous virgin queens from mating with diploid males. We focus our study on the cephalic labial gland secretions of diploid and haploid males ofBombus terrestris （L.）. Contrary to initial expectations, our results do not show any significant differentiation of cephalic labial gland secretions between diploid and haploid specimens. Queens seem therefore to be unable to avoid mating with diploid males based on their compositions of cephalic labial gland secretions. This suggests that the vortex of extinction of diploid males could not be stopped through premating avoidance based on the cephalic labial gland secretions but other mechanisms could avoid mating between diploid males and queens.
文摘Naturally-occurring and artificially-induced polyploids have been documented in various fish species but to date no comparison has been reported of the impacts of ploidy on fish biomarker responses to organic pollutants.This study describes effects of ploidy,gender,and dose on biliary fluorescent aromatic compound（FAC） concentrations,hepatic ethoxyresorufin-O-deethylase（EROD） and glutathione S-transferase（GST） activities in one of the most commonly cultured warm-water species,the African catfish Clarias gariepinus.Recently matured male and female diploid and triploid fish were intraperitoneally（i.p.）injected with 0,5 or 25 mg/kg benzo[a]pyrene（BaP） and liver and gallbladder were sampled48 hr later.No significant differences were found between ploidies in bile concentrations of7,8 dihydrodiolbenzo[a]pyrene（7,8D BaP）,1-hydroxybenzo[a]pyrene（1-OH BaP） or3-hydroxybenzo[a]pyrene（3-OH BaP）.However,concentrations of the biliary FACs did differ between males and females at different dose of injection with generally higher concentrations in females at the low dose of BaP and higher concentrations in males at the higher BaP concentration.Hepatic EROD activity did not exhibit gender-dependent difference,whereas it was significantly higher in triploids than diploids.GST activities were not significantly influenced by any of the tested factors.This work advanced our understanding of the role of ploidy,gender,and dose in biotransformation of pollutants in fish.
