Effect Of Juvenile Hormone Analogue On 10-HDA Secretion In Mandibular Glands Of Honey Bee(Apis Mellifera Ligustica)workers

The mandibular glands in the queen secret queen pheromone,while in the worker they secret 10-hydroxy-2-decenoic acid(10-HDA),which is the main unsaturate fatty acid component in royal jelly.10-HDA is the most important antimicrobial component in the larval food,and had been proved to paticipate in caste differentiation development.Juvenile hormone(JH)is the most important hormone in insect,which play important roles in larval development,caste differentiation,adult social division of labor and behavior development,gland development as well.In order to ascertain whether JHⅢ affect the development of the mandibular gland and its secretions,we studied the relationship between the JHⅢ and 10-HDA,the effect of juvenile hormone analogue(JHA)on the content of 10-HDA and ultrastructure of mandibular gland.To explore the relationship between 10-HDA in the heads and JHⅢ,both 10-HDA in the heads and JHⅢ in the body of 0,5,10,15,20-day old workers were measured by HPLC respectively,the results showed that both the quantities of 10-HDA and JHⅢ changed with the age,and there was significant positive correlation(y=3.401x-40.593,r=0.999,P<0.01)between them.This indicates that JH Ⅲ may influence the secretion of 10-HDA in mandibular gland.In order to clarify the solvent for JHA that has minimal influence on the 10-HDA synthesis in the mandibular gland.First,we should choose the solvent for JHA.Newly emerged workers of Apis mellifera L.were treated by different concentrations of DMSO,DMF,isopropyl alcohol,acetone and n-hexane respectively.After 5 μL DMSO,DMF,acetone and isopropanol treatment,the mortality was significantly(P<0.01)higher than other treatments group and the control group.When 1μL isopropanol,acetone and hexane were applied on newly emerged workers,10-HDA content of 2,5,8-day-old workers was determined by HPLC.The results showed that 10-HDA of 5-day-old workers was higher than that of the control group(P<0.05),that of 8-day-old workers treated by n-hexane was significantly(P<0.05)higher than that of the control group,the workers treated by isopropyl alcohol had no difference between control group.After 200 μg 50 μg,25 μ9 JHA and 1μL isopropanol treated newly emerged workers,the mortality of 200 μg treatment group was significantly higher than other groups including the control groups,200 μg and 50 μg could significantly(P<0.01)promoted the secretion of 10-HDA at 3-day-old9 at 5 days old 200 μg treatment group was lower(P<0.05)than the control group,10-HDA of bees treated by 25 μg was significantly(P<0.01)lower than the control group.After 200μg,50 μg,25 μg JHA and 1μL isopropanol were treated to newly emerged workers,the ultrastructure of gland cells in bees treated by 200 μg JHA showed up some myelinic bodies,chromatin condensation and marginalization at 3 days old.In cells of 200μg and 50μg treatment group microvilli and reservoir are richer than other treatment group and control groups.The number of myelinic body in 200 μg treatment group at 5 days old increases,while the number of microvilli and reservoirs in 200 μg and 25μg treatment group were less than control groups.There was high positive correlation between 10-HDA and JHⅢ.Using exogenous JHA can influence the 10-HDA content and the number of microvilli and reservoirs,the effect is timeliness.