枣疯病植原体越冬后向枣树不同类型新生组织转移特性研究

为明确枣疯病植原体越冬后向新生组织的转移扩散特点,从而指导枣疯病预防和控制,本研究采用PCR和DAPI荧光显微技术,比较枣疯病植原体向枣树不同类型新生组织的转移情况。结果表明:室内水培的疯枣枝在萌芽30d后,新生叶片可以检测到植原体;自然栽培枣树的枣股新生叶片生长发育至24d出现植原体;枣树根蘖在萌芽后12d即可检测到植原体。嫁接试验表明,嫁接于染病冬枣砧木上的易感品种接穗‘唐星’,‘阜星’,其萌发的新生幼叶在第34天即可检测到植原体,而抗病品种‘星光’接穗在第119天才检测到植原体。由此可见,枣疯病植原体在地上和地下部分均可以越冬,越冬的植原体向枣树不同类型和不同品种新生组织中的转移扩散速度存在差异,由快到慢为根蘖>自然生枝条>离体水培枝条>嫁接接穗。

Studies on migration characters of jujube witches＆#39; broom phytoplasma into newborn tissues of jujube after overwinter

It is important to clarify the transferring and migrational characters of jujube witches＇ broom （JWB） phytoplasm into newborn tissues for preventing and controlling JWB in jujube orchards. Polymerase chain reaction （PCR） and DAPI staining under fluorescence microscopy were employed to compare and analyze the transferring characteris of JWB phytoplasma into newborn tissues of jujube. The results showed that phytoplasma could be detected in new leaf of jujube hydroponic annual shoots 30 days after germination frondesce. Furthermore, phytoplasma in juvenile leaf of annual jujube stock could be observed 24 days after germination, while 12 days after germination in juvenile leaf of root sucker. The results of jujube grafting experiments indicated that phytoplasma could be detected at 34-day after germination for susceptible cultivars＂Tangxing＂and＂ Fuxing＂. Howe＇~er, it could not be detected in newborn tissue from resistant cultivar of＂ Xingguang＂ until 119 days. In summary, phytoplasma might overwinter both in root and stem. The migrational rate of JWB phytoplasmas differed significantly when transferred to different dormant sites and different newborn tissues, which could be ranked as root sucker〉branch〉 hydroponics vitro shoots〉 scion.