[Objective] The aim of this study was to compare three RNA extraction methods and thus find out the suitable one for isolating intact and high quality total RNA from Pinus bungeana.[Method] Employing three extraction methods of Trizol,RNeasy Mini Kit,LiCl precipitation,total RNAs of P.bungeana were extracted from pine leaf samples,and their integrity and purity were detected via agarose gel electrophoresis and spectrophotometry for a comparative study.[Result] Among the three extraction methods,LiCl precipitation method demonstrated higher yield and better integrity of total extracted RNA,with OD260/OD280 ratio between 1.8-2.0 and clear 28 S and 18 S bands in electrophoresis pattern.[Conclusion] LiCl precipitation method could be used to extract highly pure and intact total RNA from P.bungeana.
[ Objective ] The paper was to confirm the effect of mating and black light treatment on cryptochromes mRNA expression of Hclicoverpa armigera. [ Method ] Quantitative real-time PCR ( SYBR Green) technique was applied to detect the expression of cryptochromes gene ( cryl and cry2 ) of H. armigera under different conditions. Total RNA was extracted from the head of H. armigera, and carried out reverse transcription to synthesize cDNA after digested by DNase I. Specific primers were used to carry out quantitative real-time PCR on cryl, cry2 and EF-Ict gene, respectively. [ Result] The expression of cryl mRNA of H. ar- migera significantly decreased after exposure to black light for 2 h, the mRNA expression of cry2 was smaller than control, they had no significant difference with each other. Mating had significant effect on mRNA expression of cryl and cry2 of H. armigera, and the mRNA expression of cryl and cry2 of male and female adults showed decreasing trend with the prolongation of time after mating. [ Conclusion] The result had important significance for further studying on function of cry gene and the control of cotton bollwonn.