Studies On Screening RAPD Molecular Makers Linked To The Plants Height Character Of Castorbean

In this paper,high and dwarf parents of Castorbean were studied.By using Random Amplified Polymorphic DNA(RAPD) and Bulk Segregant Analysis(BSA),the molecular marker linked with height gene of Castorbean were investigated.The major results were as follow:1.CTAB method was used to extract DNA from castorbean leaf in this study.The RAPD-PCR influence factors were analyzed in orthogonal design method:Primers,dNTP, Taq polymerase,Mg²⁺,annealing temperature and thermal cycles were studied.An optimal PCR system of RAPD of castorbean has been found.In this system of 25μl reaction included primers 0.36μmol/L,dNTP 0.24mmol/L,Taq polymerase 0.05U/μl and Mg²⁺ 1.2mmol/L.The optimal amplification program included initial denaturing at 94℃for 2min,denaturing at 94℃for 45s,annealing at 36℃for 45s,extension at 72℃for 75s, 35 cycles and final extension at 72℃for 5mins.2.The genomic variation in high bulks and dwarf bulks parents of Castorbean was analyzed for RAPD with 200 arbitrary primers(10bp).1021 clear bands were amplified in total.2 to 13 polymorphic bands could be amplified from each primer and the band length was from 200bp to 2000bp.Selection shows:only S1500 can amplified a special primer in both high character bulk and dwarf character of castorbean individual,and this markers were identified to be linked to the height gene of Castorbean.3.S1500₂₂₀₀ and S1500₁₆₀₀ were cloned to pGEM-T Easy Vector and sequenced, S1500₂₂₀₀ marker is 2242bp and S1500₁₆₀₀ marker is 1690bp.They were named as S1500₂₂₄₂ and S1500₁₆₉₀.4.S1500₂₂₄₂ and S1500₁₆₉₀ compared to nueleotide sequence of other beings in NCBI GeneBank.The sequence is a spceific nueleotide sequence and it's Homologous is low.S1500₂₂₄₂ and S1500₁₆₉₀ compared to nueleotide sequence of each other in DNAMAN. Homologous is 35.73%.The parts of two segments were same in the place.Marker of S1500₂₂₄₂ and S1500₁₆₉₀ was heigh relative gene.