Primary Studies On The Molecular Systematics Of Braconidae(Hymenoptera)

Parastic Hymenoptera are important enemies of pest and benefit resources for biocontrol. In order to make good use of heritage resource of parastic Hymenoptera specimen, we need high quality of genomic DNA. Then we can study the species origin, system evolution, biology diversity, introduction of insect enemy, protection of insect enemy, release of insect enemy in molecular level.(1) we discuss Factors of genomic DNA degradation in Braconidae specimen. These factors include high temperature, oxidation and chemic modification. We should douse Braconidae specimen in 100% ethanol with 50mmol/L EDTA. At the same time, olefin oil should be used on ethanol level(2) By comparing some methods for extracting DNA, we find CTAB (Cetyltrimethyl Ammonium Bromide) method is the best. By optimizedmethod of CTAB, we can extract DNA in Braconidae specimen which preserved in ethanol for almost 20 years. Extracted genomic DNA can be used for RAPD-PCR analysis. The method for dry specimen needs study more.(3) An optimized RAPD-PCR reaction system for RAPD analysis was established: PCR was performed in a 25ul reaction mixture with 30~60ng DNA, 150umol/l of each dNTP, 0.2umol/l random primer, 10mniol/l Tris-HCl(PH8.0) ,50mmol/l KCl,2.5mmol/l MgCl2,andl.5U Taq polymerase. The temperature profile used for PCR was 94 for 4 min, followed by 45 cycles of94 for 15sec, 36 for45sec, and72 for l.5min, and was terminated with a 4 min DNA extension step at 72 .(4)There are polymorphic DNAs in 12 accessions. 159 DNA bands were amplified with 25 RAPD primers among which 119 (75%) were polymorphic in 4 genues of Aphidiidae. Cluster analysis based RAPD showes that Ephedrus Holiday and Fovephedrus Chen have higher genetic similarity, then withAphidius Nees,lasl with Diaeretiella Stray.