Study On DNA Extraction Method Of Dalbergia Odorifera T.Chen Based On Treatments Of Different Drying Temperature

The timber can be distinguished into the genus through the traditional timber identification technology,mainly comparing the difference of anatomical characteristics and chemical composition in different timbers.But the difference of anatomical characteristics among the close species is small,and it is difficult to identify the timber using the traditional method.With the development of molecular biology technology,molecular biology technology has been applied in many scientific fields,expecting to get a deeper breakthrough.The successful application of molecular biology technology in the field of forensic and archaeological research has provided a new method and means for the identification of timber.Extracting enough quality and quantity of DNA from timber is the precondition to identify timber by using DNA technology.Compared to those plant tissues which are fresh,tender and has the division ability,it is much more difficult for extraction and amplification of DNA in timber.Especially in the production and processing of timber products,timbers are necessary to drying process with high temperature,which further aggravates the degradation of wood DNA to increase the difficulty of DNA extraction of wood.Therefore,in this study,heartwood and sapwood of Dalbergia odorifera handled at different drying temperature?25?,40?,60?,80? and 105??were selected as the subject investigated.Different parts of the timber DNA in Dalbergia odorifera disposed at different drying temperature were extracted by modified SDS method,CTAB and PTB method,and DNA bar code sequences in the chloroplast?trnH-psbA and rbcL?and ITS2 nuclear were amplified.As for the differences of DNA extraction quality in diverse parts of Dalbergia odorifera at different drying temperature,three DNA extraction methods were compared,and the effects of different drying temperature on extraction of DNA in Dalbergia odorifera timber were analyzed,exploring the optimal DNA extraction method.The results are as follows:1.Heartwood and sapwood DNA in Dalbergia odorifera without the drying process were extracted by modified SDS method,CTAB method and the PTB method respectively,followed by concentration and purity detection of purificated DNA.The effect of different DNA extraction methods on the DNA concentration,purity and different positions was analyzed.The results showed that sapwood DNA concentrations extracted by improvedSDS method and CTAB method were 88.4 ng/?L and 20.86 ng/?L and A₂₆₀/A₂₈₀ values were 1.96 and 2.00 while average concentration of heartwood DNA were 5.5 ng/?L and5.9 ng/?L and A₂₆₀/A₂₈₀ values were 1.85 and 1.58.The sapwood and heartwood DNA concentration extracted by PTB were 58.5 ng/?L and 14.8 ng/?L and A₂₆₀/A₂₈₀ values were 2.80 and 2.82.Therefore,the quality of DNA extracted by improved SDS method and CTAB method were superior to PTB method;the concentration and purity of sapwood DNA extracted by three DNA extraction methods were higher than that of heartwood.2.Dalbergia dalbergia timbers were embalmed at different drying temperature for24 h,and then heartwood and sapwood DNA were extracted respectively by using modified SDS method,CTAB and PTB method to observe the effects of different drying temperature on the concentration and purity of DNA in timber.The results indicated that the sapwood DNA concentration decreased gradually with the increase of drying temperature,and the sapwood DNA concentration is the lowest at 105?.The heartwood DNA concentration increased not obviously,and the purity of heartwood was inferior to that of sapwood.and the purity of heartwood DNA extracted by improved SDS method was best.3.Dalbergia dalbergia timbers were embalmed at different drying temperature for24 h,and then heartwood and sapwood DNA were extracted respectively by using modified SDS method,CTAB and PTB method to analyze the effects caused by different drying temperatures on the amplification of barcode sequence in Dalbergia dalbergia.The results revealed that the amplification effect of sapwood is better than that in sapwood with the increase of drying temperature.trnH-psbA sequence in heartwood treated at 105? could be amplified only by improved SDS method.