Effects of copper (Cu) accumulation by the flesh fly Boettcherisca peregrina (R.- D.) (Diptera: Sarcophagidae) on the ectoparasitic wasp Nasonia vitripennis (Walker) (Hymenoptera: Pteromalidae) were invest...Effects of copper (Cu) accumulation by the flesh fly Boettcherisca peregrina (R.- D.) (Diptera: Sarcophagidae) on the ectoparasitic wasp Nasonia vitripennis (Walker) (Hymenoptera: Pteromalidae) were investigated experimentally by exposing host larvae to contaminated diets with final Cu concentrations of 400μg/g and 800μg/g diet fresh weight (DFW), respectively. Results showed that Cu can be transferred along food chains to secondary consumers (parasitoids) in small amounts, resulting in negative effects on parasitoid growth and development (body weight and developmental duration) as well as fecundity (number of offspring per female). Copper exposure also inhibited vitellogenesis ofparasitoids from Cu-contaminated host pupae. It is suggested that the decreased fecundity and inhibition of vitellogenesis ofN. vitripennis resulted from poor host nutritional state rather than from direct effects of Cu stress.展开更多
A female-specific protein, vitellogenin (Vg), and its corresponding egg vitellin (Vt) are identified in the ectoparasitic wasp Nasonia vitripennis. Both native Vt and Vg have a molecular mass of about 350 kDa, whi...A female-specific protein, vitellogenin (Vg), and its corresponding egg vitellin (Vt) are identified in the ectoparasitic wasp Nasonia vitripennis. Both native Vt and Vg have a molecular mass of about 350 kDa, which is composed of two subunits of approximately 190 kDa and 165 kDa under reducing and denaturing conditions (sodium dodecyl sulfate-polyacrylamide gel electrophoresis). An indirect sandwich enzyme-linked immunosorbent assay developed with both monoclonal and polyclonal antibodies against N. vitripennis Vt. Vg was first detected in the hemolymph on the 10th day after parasitism, and was first observed in oocytes on the 12th day. In adults deprived of food, the highest hemolymph Vg level occurred at the time of adult eclosion and the highest level of Vt in ovaries was found at 30 h after eclosion. In contrast, feeding adults with 20% sucrose resulted in the reduction of Vt uptake by ovaries and the extension of life span, but had little effect on Vg production. Deprived of hosts, starvation of female wasps had no significant effects on ovariole growth and oocyte maturation before the wasps died. However, starvation of female wasps supplied with hosts accelerated the wasps laying progeny into hosts, but resulted in a decrease of total progeny production by comparison with wasps fed with 20% sucrose.展开更多
基金Acknowledgments This work was supported by the National Basic Research and Development Program of China (2006CB 102005), the National Natural Science Foundation of China (Grants No. 30230070, 30270899), the Program for New Century Excellent Talents in University of the Ministry of Education of China (NCET-05-0513), and the Innovation Research Team Program of the Ministry of Education of China (Grant No. IRT0535).
文摘Effects of copper (Cu) accumulation by the flesh fly Boettcherisca peregrina (R.- D.) (Diptera: Sarcophagidae) on the ectoparasitic wasp Nasonia vitripennis (Walker) (Hymenoptera: Pteromalidae) were investigated experimentally by exposing host larvae to contaminated diets with final Cu concentrations of 400μg/g and 800μg/g diet fresh weight (DFW), respectively. Results showed that Cu can be transferred along food chains to secondary consumers (parasitoids) in small amounts, resulting in negative effects on parasitoid growth and development (body weight and developmental duration) as well as fecundity (number of offspring per female). Copper exposure also inhibited vitellogenesis ofparasitoids from Cu-contaminated host pupae. It is suggested that the decreased fecundity and inhibition of vitellogenesis ofN. vitripennis resulted from poor host nutritional state rather than from direct effects of Cu stress.
基金Acknowledgments This work was supported by the National Basic Research and Development Program of China (2006CB 102005), the National Natural Science Foundation of China (Grant No. 30270899), the program for New Century Excellent Talents in the University of the Ministry of Education of China (NCET-05-0513), and the Innovation Research Team Program of the Ministry of Education of China (Grant No. IRT0535).
文摘A female-specific protein, vitellogenin (Vg), and its corresponding egg vitellin (Vt) are identified in the ectoparasitic wasp Nasonia vitripennis. Both native Vt and Vg have a molecular mass of about 350 kDa, which is composed of two subunits of approximately 190 kDa and 165 kDa under reducing and denaturing conditions (sodium dodecyl sulfate-polyacrylamide gel electrophoresis). An indirect sandwich enzyme-linked immunosorbent assay developed with both monoclonal and polyclonal antibodies against N. vitripennis Vt. Vg was first detected in the hemolymph on the 10th day after parasitism, and was first observed in oocytes on the 12th day. In adults deprived of food, the highest hemolymph Vg level occurred at the time of adult eclosion and the highest level of Vt in ovaries was found at 30 h after eclosion. In contrast, feeding adults with 20% sucrose resulted in the reduction of Vt uptake by ovaries and the extension of life span, but had little effect on Vg production. Deprived of hosts, starvation of female wasps had no significant effects on ovariole growth and oocyte maturation before the wasps died. However, starvation of female wasps supplied with hosts accelerated the wasps laying progeny into hosts, but resulted in a decrease of total progeny production by comparison with wasps fed with 20% sucrose.