The stinging response thresholds of individual European and Africanized worker honeybees (Apis mellifera L.) were analyzed. Workers of each genotype performing defense (guard and soldier bees) and non-defense (nest an...The stinging response thresholds of individual European and Africanized worker honeybees (Apis mellifera L.) were analyzed. Workers of each genotype performing defense (guard and soldier bees) and non-defense (nest and forager bees) associated tasks were collected and exposed to an electric stimulus of 0.5 mA, and the time they took to sting a leather substrate was recorded. Africanized bees had significant lower thresholds of response than European bees. Guards and soldiers were faster to sting than nest and forager bees for the Africanized genotype, whereas for the European genotype, guards stung significantly faster than bees of the other three task groups. This is the first study that shows that individual bees specialized in two defensive tasks also have a lower response threshold for stinging. Our results fit a model of division of labor based on differences in response thresholds to stimuli among workers of different genotypes and task groups.展开更多
Intra-abdominal injection of amitraz(0.25 nmol per honeybee,i.e.,approx 2.3 nmol/g)to emerging worker bees,in vivo,led to a significant hypertrehalosemia(300-400%)followed by a hyperglucosemia(≈600%).Maxima were reac...Intra-abdominal injection of amitraz(0.25 nmol per honeybee,i.e.,approx 2.3 nmol/g)to emerging worker bees,in vivo,led to a significant hypertrehalosemia(300-400%)followed by a hyperglucosemia(≈600%).Maxima were reached at 0.5 and 2h,respectively.A strong negative correlation between glucosemia and trehalosemia appeared after injection of pure phentolamine (1 nmol per bee),suggesting stimulation of trehalase activities.Simultaneous administration of the α-blocker at≥0.25 nmol per individual suppressed the hyperglycemic response of amitraz. The formamidine pesticide thus likely acts on the honeybee α-aminergic system.1989 Academic Press,Inc.展开更多
The esterase (EST) and the malate dehydrogenase Ⅱ (MDHⅡ) isozymes in A. mellifera carpatica (C), A. mellifera ssp.(D), “Zhejiang Agricultural University No.1” A. mellifera ligustica (Ea) and A. mellifera carnica (...The esterase (EST) and the malate dehydrogenase Ⅱ (MDHⅡ) isozymes in A. mellifera carpatica (C), A. mellifera ssp.(D), “Zhejiang Agricultural University No.1” A. mellifera ligustica (Ea) and A. mellifera carnica (K), and the genotypes of MDHⅡ isozymes in four subspecies of A. mellifera were analysed by IEF PAGE. The results indicate that the four subspecies of A. mellifera showed the same EST zymogram, while A. cerana showed a different EST zymogram, which suggests that the genotypes of EST isozymes in A. mellifera are different from those in A. cerana. The genotypes of the MDHⅡ isozymes in four subspecies of A. mellifera were aa, ab, ac, bb, bc and cc. The C and Ea subspecies exhibited high homozyosity, while D and K displayed high heterozyosity. The allele b appeared to be the highest frequency in C, while the allele c had the highest frequency in Ea. The frequencies of the alleles a, b and c in sub species D were very similar. The alleles a and c were common, while allele b was rare in sub species K. There were highly significant differences in genotype frequencies, allele frequencies, homozyosity and heterozyosity among these four subspecies.展开更多
文摘The stinging response thresholds of individual European and Africanized worker honeybees (Apis mellifera L.) were analyzed. Workers of each genotype performing defense (guard and soldier bees) and non-defense (nest and forager bees) associated tasks were collected and exposed to an electric stimulus of 0.5 mA, and the time they took to sting a leather substrate was recorded. Africanized bees had significant lower thresholds of response than European bees. Guards and soldiers were faster to sting than nest and forager bees for the Africanized genotype, whereas for the European genotype, guards stung significantly faster than bees of the other three task groups. This is the first study that shows that individual bees specialized in two defensive tasks also have a lower response threshold for stinging. Our results fit a model of division of labor based on differences in response thresholds to stimuli among workers of different genotypes and task groups.
文摘Intra-abdominal injection of amitraz(0.25 nmol per honeybee,i.e.,approx 2.3 nmol/g)to emerging worker bees,in vivo,led to a significant hypertrehalosemia(300-400%)followed by a hyperglucosemia(≈600%).Maxima were reached at 0.5 and 2h,respectively.A strong negative correlation between glucosemia and trehalosemia appeared after injection of pure phentolamine (1 nmol per bee),suggesting stimulation of trehalase activities.Simultaneous administration of the α-blocker at≥0.25 nmol per individual suppressed the hyperglycemic response of amitraz. The formamidine pesticide thus likely acts on the honeybee α-aminergic system.1989 Academic Press,Inc.
文摘The esterase (EST) and the malate dehydrogenase Ⅱ (MDHⅡ) isozymes in A. mellifera carpatica (C), A. mellifera ssp.(D), “Zhejiang Agricultural University No.1” A. mellifera ligustica (Ea) and A. mellifera carnica (K), and the genotypes of MDHⅡ isozymes in four subspecies of A. mellifera were analysed by IEF PAGE. The results indicate that the four subspecies of A. mellifera showed the same EST zymogram, while A. cerana showed a different EST zymogram, which suggests that the genotypes of EST isozymes in A. mellifera are different from those in A. cerana. The genotypes of the MDHⅡ isozymes in four subspecies of A. mellifera were aa, ab, ac, bb, bc and cc. The C and Ea subspecies exhibited high homozyosity, while D and K displayed high heterozyosity. The allele b appeared to be the highest frequency in C, while the allele c had the highest frequency in Ea. The frequencies of the alleles a, b and c in sub species D were very similar. The alleles a and c were common, while allele b was rare in sub species K. There were highly significant differences in genotype frequencies, allele frequencies, homozyosity and heterozyosity among these four subspecies.