Detection, Identification, and Molecular Characterization of the 16SrII-V Subgroup Phytoplasma Strain Associated with Digera muricata in Taiwan

• Published in: Plant disease p. PDIS12212647SC
• Main Authors: Mejia, Helen Mae, Liao, Pei-Qing, Chen, Yuh-Kun, Lee, Ya-Chien, Tan, Choon Meng, Chiu, Yi-Ching, Yang, Jun-Yi
• Format: Journal Article
• Language: English
• Published: United States 01.07.2022
• Subjects: iPhyClassifier; phytoplasma; SAP11; Digera muricata (L.) Mart; PHYL1
• ISSN: 0191-2917
• DOI: 10.1094/PDIS-12-21-2647-SC

(L.) Mart. is a pantropical annual herb belonging to the Amaranthaceae family. In August 2021, with indicative phytoplasma symptoms of phyllody, witches'-broom, and virescence was discovered adjacent to a peanut field in Mailiao, Yunlin, Taiwan. The causal agent of the observed symptoms was detected and identified by a series of molecular characterizations. Sieve elements of the phloem tissue were perused under the transmission electron microscope and revealed the presence of pleomorphic phytoplasma-like organisms. Nested PCR using phytoplasma universal primer pairs P1/P7 and R16F2n/R16R2 was able to amplify a 1.2-kb DNA fragment for the gene only from the symptomatic . The -based phylogenetic analysis and the PhyClassifier-based virtual RFLP further affirmed that the phytoplasma associated with the diseased can be classified into the 16SrII-V subgroup. Moreover, displayed evident symptoms were explained by the concomitant detection of and , the virulence genes responsible for the development of leaf-like flowers and shoot proliferation, respectively. Although phytoplasma infection on the noncrop species does not have a direct economic impact, its role in disease spread and perpetuation is indubitable.