Abstract: This work is to find out the effects of different precipitation methods on the latex total RNA and amplification efficiency of PCR as well as to seek the better precipitation method. According to the characteristics that Herva brasiliensis latex was rich in proteins,polysaccharides and rubber particles,on the basis of SDS method modified in our laboratory,the total RNA in the latex of H. brasiliensis was precipitated respectively with LiCl,NaCl + isopropanol,NaCl + NaAc + absolute ethanol,and NaAc + absolute ethanol,and then the integrity of the RNA,purity,content,and RT-PCR amplification efficiency were compared. The results indicated that complete RNA was obtained by any of 4 methods. But the differences in purity and content of RNA and amplification efficiency of RT-PCR among 4 methods were also observed. In which the purity and yield of total RNA precipitated with NaCl + NaAc + absolute ethanol and 18S and REF gene amplification efficiency of latex tissues in rubber tree were higher,indicating that NaCl + NaAc + absolute ethanol was effective method to precipitate total RNA.

Key words: Hevea brasiliensis latex, total RNA extraction, RNA precipitation