Optimization of chromosome preparation and karyotype analysis of triploid Paeonia lactiflora variety
In order to optimize the chromosome preparation method of triploid Paeonia lactiflora,the newly-grown white root tips of triploid Paeonia lactiflora'Fairy Princess'were used as materials,and the effects of pretreatment reagents and pretreatment time on chromosome preparation were obtained by conventional chromosome preparation method,and the karyotype was analyzed.The results showed that the optimum pretreatment time of 0.002 mol/L 8-hydroxyquinoline solution,saturated p-dichlorobenzene solution and 0.10%colchicine solution was 12~36 h,24 h,and less than 48 h,respectively.When pretreatment was for 12~60 hours,the best pretreatment reagent was 0.002 mol/L 8-hydroxyquinoline solution.After pretreatment for 72 h,the best pretreatment reagents were 0.002 mol/L 8-hydroxyquinoline solution and saturated p-dichlorobenzene solution.The karyotype formula of 'Fairy Princess'was 2n=3x=15=10m+2sm+3st.The karyotype was classified as type 2A.The results provided chromosome information for the application of triploid Paeonia lactiflora and provide basis for long-term preservation of field materials.