Disease Severity Assessing and Molecular Identification of Pathogen Associated with Witches' Broom Disease of Phyllostachys praecox

Objective In this study, the witches' broom disease of Phyllostachys praecox was assessed, and the pathogen of the disease was identified through molecular biology techniques.

Method The disease severity was assessed by grading witches' broom disease at individual level and branch level. The pathogen of witches' broom disease of Ph. praecox was identified by specific PCR primers of phytoplasmal 16S rDNA and fungal rDNA-ITS sequences.

Result Disease assessment data showed that the average incidence of the 6 plots was 18.59%, and the average disease index was 6.67. PCR results indicated that all the samples infected were able to amplify rDNA-ITS sequence of fungus, and could not amplify 16S rDNA of phytoplasma. Comparative BLAST analysis determined that the amplicons shared 99.00% similarity with sequences from Aciculosporium take, and the highest similarity with other fungi was only 94.00%.

Conclusion A. take was the causal agent of witches' broom disease of Ph. praecox of Deqing County, Zhejiang Province.