| Bradysia odoriphaga Yang et Zhang is the main pest damaging theLiliaceae vegetables (such as leek, garlic, onion etc.), Asteraceae vegetables(such as lettuce) and edible fungi. At present, some researches on ovariandevelopment and vitellogensis of insects is the important field in insectphysiology. As we all know, vitellogenesis of insects is one of the mostimportant fields in insect physiology, insect biochemistry, insect molecularbiology, insect molecular endocrinology and inmmaunochemistry. This paperdelt with the preliminary researches on ovarian development andvitellogenesis of Bradysia odoriphaga in order to forecast and control the pestscientifically and in order to verify the synthesis time, the dynamic, thetransportation and the uptake of vitellogenin (Vg).1. According to the morphological characters of pupa (body color andcompound eyes development), the different stages of pupa and adult weredissected, and the structure of the female reproductive system was got, thedevelopmental features of ovarian and fat body development were described.Using the length and width of ovary and egg, by means of systematic cluster(Word's method), ovarian development from propupa to adult were classifiedinto 5 grades, and ovarian development of pupa 4 grades. These researchesprovide the basis for prediction and control of the pest.2. The histological characters of ovary structure were studied bysemi-thin section techniques. The results showed that the ovariole consists ofone nurse cell, one oocyte and some follicular cells around the nurse cell andoocyte.The ultrastructure of the fat body and ovary of the main stages wasresearched by transmission electronic microscope, the structure features ofsubcell in fat body and ovarioles, the dynamics of vitellogenin synthesis in fatbody, the changes of ovarian structure during vitellogenesis and uptake ofvitellogenin were described. Before the synthesis of vitellogenin in the fat body, there were many lipiddroplets, protein granules, mitochondrions, and a little rough endoplasmicreticulum. Sometimes the multivesicular body was observed, all the subcellorganelles showed that the fat body mainly stored the protein beforevitellogenin synthesis. But during the vitellogenin synthesis, many roughendoplasmic reticulums existed in the fat body with rich lipid droplets andprotein granules, which showed that much vitellogenin was synthesized in thefat body. At the end of vitellogenesis (at the stages of grey and black pupa),rough endoplasmic reticulum got smaller and some turned into bubbles. Mostof protein granules moved to the periphery of the fat body so as to transportthe vitellogenin into ovaries easily. The researches on the changes of ultrastructure of the ovary showed thenurse cells were larger than the oocytes, and there were no vitellogenin existedin the oocyte before vitellogenin synthesis; but during vitellogenin synthesis,the oocytes got bigger with many protein granules and lipid droplets, showingthat vitellogenin synthesized in the fat body continually transported to theovaries. During the peak and the late of vitellogenesis, the patency between thefollicular cells appeared, many vitellogenin particles located between oocyteand follicular cells. Many microvilli existed in the membrane of oocytes,showing that Vg entered the developing oocyte by endocytosis. At last, thevitellogenin deposition ended in adult, the oocyte was full of vitellin (Vn),meanwhile, the follicular cell secreted chorion. 3. The vitellogenin in fat body and hemolymph and the vitelline in ovaryand egg were identified by native-PAGE. The molecular weight of vitellogeninis 161.5KD, and Vitelline is 145.6KD. 4. The soluble protein in the fat body and ovary of pupa, the ovary ofadult and egg were determined, the results showed that the contents of soluble...
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