【作者】 田铃；

【导师】 嵇保中；

【作者基本信息】 南京林业大学 ， 森林保护学， 2008， 博士

【摘要】 本文以桑天牛为对象,研究了雌、雄成虫内分泌器官咽侧体-心侧体复合体(Corpora allata and corpora cardiaca,CA)及生殖器官在JH生物合成中的功能与角色分化,保幼激素(JH)和MAG内容物对雌虫生殖行为的影响。主要结果如下:1.描述了桑天牛生殖系统解剖构造,测定了桑天牛血淋巴、生殖系统内容物成分及pH,研究了交配活动对血淋巴、生殖器官内蛋白质和可溶性总糖含量的影响。2.MAG、精巢、卵巢可以利用甲硫氨酸(Met)合成JH,而雌、雄成虫的CA均无合成能力。放射化学法离体培养发现雄性附腺(MAG)和精巢合成JH的最高峰分别出现在培养6h、8h。3.高效液相色谱(High performance liquid chromatography,HPLC)检测发现桑天牛成虫JH生物合成遵循法尼酸(FA)→甲基法尼酯(MF)→JH途径。雌、雄成虫的CA可利用法尼醇(Farnesol)合成FA但不能合成MF、JHⅢ。精巢、MAG、卵巢具有利用MF合成JHⅢ的能力。CA合成的FA被释放进入血淋巴后,被来自血淋巴的甲基转移酶合成MF,MF在各生殖器官内形成JHⅢ。4.28℃下暗光孵育30h的胚胎开始利用3H-Met合成JH,胚胎合成JH亦遵循FA→MF→JH途径。胚胎时期MF与FA为主要的JH形式。对初孵幼虫与卵壳的分别检测中发现:卵壳上没有JHⅢ,但仍有未被胚胎利用完的FA和MF存在,初孵幼虫体内的FA、MF、JH来源不同。5.将掺有3H-Met的Medium 199培养液注入雄虫体内,饲养24h后与无放射性的雌虫进行交配,发现:交配前、后,雄虫的血淋巴、CA、生殖系统、MAG内均有放射性;交配后MAG内的放射性含量明显降低。配对雌虫血淋巴、CA、卵巢均可以检测到放射性。HPLC检测发现,交配后雄虫血淋巴内的JHⅢ含量无变化,MAG内的JHⅢ含量降低了41.63%,配对雌虫血淋巴和卵巢内的JHⅢ含量均明显增加。6.以18℃、4℃下pH 7.0的磷酸缓冲液为工作环境。卵巢离体检测发现,标样JH和MAG内容物均能促进卵巢对卵黄原蛋白(Vitellogenin,Vg)的摄取。将标样JH和MAG内容物注射入桑天牛雌虫体内,发现JH和MAG内容物对雌虫的产卵量、寿命、取食量都具有促进作用,桑天牛的生殖调控为JH主导型。更多还原

【Abstract】 In this thesis,A. germari was chosen as the study object for researching JH biosynthetic mechanism.The biosynthetic ability of JH in its endocrine and reproductive organs were studied.The effects of JH on reproduction were also researched. The main results as follows:1.The reproductive systems of male and female adults were both described for the first time. The contents of the total carbohydrate and protein in the hemolymph, male reproductive systems, MAG,ovaries from both virgin and mated males and females were tested.The pH in above tissue and organs were also detected.2. Results showed that CA couldn’t synthesize JH independently,the testis, MAG and ovary of A. germari were found as organs finally to synthesize JHⅢ. By the use of radiochemical assay,the biosynthetic rate of JH in MAG and testis in vitro were studied.The highest biosynthetic rate of JH in MAG and testis was respectively at 6h and 8h.3. By the use of HPLC,we found that the biosynthetic pathway of JHⅢin A. germari adults was from FA to MF and then MF was converted to form JHⅢ. The CA of both sexes could use farnesol to synthesize FA,FA couldn’t be converted to form MF and JHⅢin CA.Testis,MAG and ovary could use MF to synthesize JHⅢby adding MF.The biosynthetic product of CA was FA.It was methylated to form MF by methyltransferase coming from haemolymph when there is methyl donor.MF finally completed the epoxidation to form JHⅢin above reproductive organs.4.After incubated for 30h in dark under 28℃,the embryo begun to synthesize JH with 3H-Met.The biosynthetic pathway of JHⅢwas from FA to MF and then to JH.It was inferred that FA and MF were the main form of JHs in embryo.The respective detection of neonatal larvae and oothecae showed that JHⅢonly existed in larvae,but there were large amount of FA and MF on oothecae.It meaned that the JHs in neonatal larvae originated from female and synthesized by itself.5.Medium 199 containing 3H-Met was injected into male adults.After raised for 24h,some male were chosen to mate with female,the radioactivity in haemolymph,reproductive system of mated female were detected.Results showed that there were large amount of radioactivity in male haemolymph and reproductive system before and after mating.The radioactivity in MAG obviously decreased after mating.By the use of HPLC,we found that the content of JHⅢin mated MAG decreased for 41.63%,but it almostly didn’t change in haemolymph.The content of JHⅢin mated female haemolymph and ovary both increased.6. The phosphate buffers(pH 7.0) under 18℃and 4℃which contained hemolymph were chosen as culture condition. Effects of JHⅢand MAG secretions on the uptake of vitellogenin were tested.Results showed that both of JHⅢand MAG secretions could stimulated the uptake of Vg.The best dissolved liquid system was choseMeanwhile, the JH and MAG secretions was injected into female,both of them can increased the feeding amount,female receptivity, fecundity in vivo.更多还原