Molecular Detection And Identification Of Four Phytoplasmal Diseases

The phytoplasmas associated with goldenbell flower yellows, umbrella tree whitening , apple leaf yellows and Sophora alopecuroides yellows were identified.The main results are as follows:Collecting the yellow leaves of Goldenbell flower in Tai'an of Shandong Province,and then the 16S rRNA gene was amplified with nested-PCR.Sequence analysis results showed that the phytoplasma belonged to subgroup16SrV-B of 16SrV.Phytoplasma from umbrella tree with leaf whitening in Tai'an of Shandong Province was detected, a specific fragment about 1.2kb in length was amplified with PCR.The fragment was sequenced and subjected to RFLP and phylogenetic analysis.The sequence analysis showed that the phytoplasma belongs to subgroup 16SrI-B of aster yellows group.Yellow leaves of apple collected from Alaer of Xinjiang province were assayed by polymerase chain reaction (PCR), a 1.2 kb fragment of 16S rRNA gene and an 800bp fragment of elongation factor gene were obtained and sequenced respectively. The sequences of 16S rRNA gene and tuf gene were inputed to pDRAW32 software for in silico restriction digestion and virtual gel plotting. Combining the results of phylogenetic analysis, we classified apple leaf yellows phytoplasma into subgroups 16SrI-B, tuf I-B .The 16S rRNA gene was amplified from Sophora alopecuroides yellows in alaer of Xinjiang province,the sequence analysis results showed that the obtained phytoplasma belongs to subgroup 16SrI-B of aster yellows group.