Establishment Of Peach In Vitro Rapid Propagation System And Regeneration Of Adventitious Buds

In this study,the stem segments of the peach cultivars‘Tiantaowang',‘Jintong 5'and the hybrid offspring‘1-6'?‘Qinwang'בZhongyou 16'?and the wild species‘Shantao'are used as explants to establish an in vitro rapid propagation system.The leaves of sterile seedlings of‘Shantao'and'1-6'were used as materials to test the regeneration of adventitious buds and the antibiotic susceptibility of peach leaves,which provided a basis for the establishment of peach genetic transformation system.The main results are as follows:?1?Establishment of peach in vitro rapid propagation system:The stem segments of‘Tiantaowang'and‘Jintong 5'are used as explants.The most suitable method for disinfection and sterilization is:75%alcohol 30 s and 0.1%HgCl₂ solution for 10 min.The contamination rate and germination rate of stem segments are:33.56%and 29.19%,89.48%and 84.82%,respectively.The primary medium suitable for germination of‘Tiantaowang',‘Jintong 5',and‘1-6'stem segments is MS+1.5 mg/L 6-BA+0.5 mg/L IBA.The germination rates are:92.17%,90.21%,and 93.33%;The contamination rate and germination rate of the stem segments are not affected by the variety and physiological age.There is a difference between the optimal subculture medium and the maximum proliferation coefficient of‘Shantao'and‘1-6'.The medium suitable for subculture of‘Shantao'is MS+1.5 mg/L 6-BA+0.3 mg/L IBA,and the maximum proliferation coefficient was 5.62.The most suitable medium for the proliferation of‘1-6'is MS+1.0mg/L 6-BA+0.1 mg/L IBA with a maximum proliferation coefficient of 3.50.The most suitable medium for rooting of‘Shantao'is MS+0.8 mg/L IBA.The rooting rate is 25.00%and the average rooting number is 1.79.The most suitable medium for rooting of‘1-6'is1/2 MS+0.5 mg/L NAA,the highest rooting rate is 36.67%,and the average rooting number is 1.76.?2?Adventitious bud regeneration of peach leaves:The ability of adventitious bud regeneration of‘1-6'?cultivar?and‘Shantao'?wild species?was compared.After 3 weeks of dark culture,the callus formed by the‘Shantao'leaves was larger and denser than the callus formed by the‘1-6'leaves;After 3 weeks of light culture,the callus of‘Shantao'leaves regenerated adventitious buds and the callus of‘1-6'leaves did not regenerate adventitious buds.Therefore,the regeneration ability of‘Shantao'leaves is stronger than‘1-6'.Yunzhi polysaccharide has no obvious promoting effect on the formation of callus of‘Shantao'.After 3 weeks of dark culture,the callus formation rate of‘Shantao'was the highest when the concentration was 2 g/L,and the callus formed at this time was better.After light culture,the callus browning of leaves containing high concentration of Yunzhi polysaccharide was more serious;All treatments did not regenerate adventitious buds.Silver nitrate has no obvious promoting effect on the regeneration of adventitious buds of‘1-6'leaves.However,the callus formed in the medium containing silver nitrate had no browning after being cultured for 3 weeks under light,and the higher the concentration of silver nitrate,the deeper the green of the callus.The concentration of silver nitrate suitable for callus formation of peach leaves is 0.5 mg/L.In the end,no adventitious buds were regenerated.?3?Peach leaf antibiotic susceptibility test:Using the leaves of‘Tiantaowang'as the material,the sensitivity of kanamycin and cephalosporin in peach leaves was tested.It was found that the resistance screening of peach leaves was suitable when kanamycin was 20mg/L.It is suitable to add 200 mg/L cephalosporin when the peach leaves are co-cultured.