Studied on Amplificative Efficiency of PCR of Predigested template DNA and GC Contents for RAPD Analysis in the Silkworm, Bombyx mori
RAPD-PCR(Random Amplified Polymorphic DNAs-Polymerase Chain Reation) 기법에 누에의 유전적 변이 분석을 위한 첫 단계로 다양한 GC함량을 갖는 random primer에 의해서 증폭되는 DNA 단편의 양상 및 증폭도를 비교하였다. RAPD-PCR을 위한 random primer의 증폭도는 GC함량에 의해서 상당히 영향을 받음이 분석되었다. 특히, 50% GC 함량을 갖는 primer는 그 증폭도에 따라서 4가지의 그룹으로 DNA단편이 증폭되었으며 〔bad amplification (75.5%), poor amplification (11.1%), good and excellent amplification(11.1%)〕, primer의 GC 함량이 증가할수록, 휠씬 더 좋은 증폭도를 보여주었다. 그러나, 40% GC 함량을 갖는 primer에 의해서는 어떤 증폭산물도 관찰되지 않았다. PCR을 수행하기 전에 6가지의 제한효소(BamHI, HindIII, Xbal, HaeIII, MspI, Rsal)를 사용하여 누에 genomic DNA를 처리하여 이를 주형 DNA로 하여 RAPD-PCR을 수행한 결과, 유전적 마커의 생산에 대한 효율이 증가함을 알 수 있었다. 이상의 결과를 종합해 볼 때 60%이상의 GC함량을 갖는 random primer와 전처리한 주형 DNA의 사용은 여러 가지 다른 누에 계통의 동정 및 연관군 지도작성에 따른 경비 및 시간을 줄이는데 효율적이라고 사료된다.
This experiment was carried out to evaluate the effect of sublethal doses of BPMC, etofenprox, and buprofezin on N. lugens. and its predator C. lividipennis. Buprofezin was found to be the most toxic to N. lugens and the most safe to C. lividipennis among the three insecticides, based on LD50 values. Selective toxicity index calculated by dividing LDSo value of C. lividipennis by that of N. lugens indicated that buprofezin was very safe to C. lividipennis, showing selective toxicity of 2703.3. Longevity and fecundity of N. lugens treated with LDIU and LDm of buprofezin and BPMC were not significantly different with those of untreated brown planthoppers. However, egg hatchability' of N. lugens was greatly reduced when treated with LDm of buprofezin, having the highest inhibition rate of 17.7%. Hatchability of eggs from insects treated with BPMC was similar to that of control. The oviposited peak of treated hoppers appeared late as compared to the untreated which showed the peak at early part of the ovipositional period. The longevity and fecundity of C. lividipennis treated with BPMC were significantly reduced as compared with the untreated. Etofenprox also induced fecundity reduction when treated with LDlo, and LDm. However, C. lividipennis treated with sublethal doses of buprofezin showed no redution in logevity and fecundity. From these results, it may be said that buprofezin can be used to control brown planthopper without disrupting of C. lividipennis population in the rice field.