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Symptoms of mango malformation and witches’ broom were observed in mango orchards at Ludhiana, Punjab, India during 2020. Phytoplasmas were detected in the symptomatic mango samples by polymerase chain reaction with specific primer pairs amplifying 16S rRNA and secA genes. Pair wise sequence comparison and phylogenetic analysis of 16S rRNA and secA gene sequences of mango phytoplasma strains indicate their relatedness with phytoplasmas in the aster yellows group. In silico RFLP analyses using the iPhy Classifier of the 16S rDNA sequence of the mango phytoplasma allowed its classification into the 16SrI-D subgroup. This is first report of this phytoplasma in mango plants showing a malformation and witches’ broom disease.

Ziziphus oenoplia, also known as jackal jujube or small fruited jujube is a spiny, evergreen small tropical fruit tree. During a survey in October-November 2019, the jujube trees exhibited severe witches’ broom symptoms, therefore, an investigation was carried out, to verify the presence of phytoplasmas in these symptomatic plants. Total DNA was extracted from leaves of jujube plants using a CTAB method and a PCR assay was performed using 16S rRNA gene specific primer pairs P1/P7 and 3Far/3Rev. Amplicons of about 1.3 kb were consistently amplified from all the symptomatic plant samples in nested PCR assays, while, no amplification was observed in non-symptomatic samples. The phylogenetic analysis of 16Sr DNA sequence of the detected phytoplasma strain indicates its clustering with ‘Candidatus Phytoplasma balanitae’ strains and also its close relatedness to 16SrV-F subgroup phytoplasmas. The virtual RFLP analysis of the 16Sr DNA sequence revealed that it could tentatively be classified into a novel phytoplasma subgroup since its AluI restriction profile was unique to earlier reported subgroup strains in 16SrV group.

Phytoplasma suspected symptoms of little leaf, chlorosis, yellowing, phyllody, witches’ broom, flat stem, flower virescence and stunting were observed in sixteen plant species during surveys in fields, gardens, fruit orchards and nurseries of six districts of Tripura, India in 2017–2018. Out of 15 symptomatic plant samples belonging to different species, 12 were positive through nested PCR assays for phytoplasma presence. Pair wise sequence comparison, phylogeny and virtual RFLP analysis of phytoplasma partial 16S rDNA sequences of these 12 samples indicated the presence of different phytoplasma groups and subgroups (16SrI-B, 16SrII-D, 16SrVI-D, 16SrXIV-A 16SrI, 16SrIX and 16SrXI). ‘Candidatus Phytoplasma asteris’-related phytoplasmas (16SrI-B) were identified in sesame phyllody affected plants at South Tripura and in crape jasmine, Celosia argentea and Zinnia elegans from Unakoti, Dhalai, North Tripura and West Tripura district. In West Tripura ‘Ca. P. australasiae'related phytoplasmas (16SrII-D) were identified with Jatropha hastata and bitter gourd; ‘Ca. P. trifolii’-related phytoplasmas (16SrVI-D) were identified in chili and brinjal and ‘Ca. P. cynodontis’-related phytoplasmas (16SrXIV-A) were identified in palm grass samples from Sipahijala district. ‘Ca. P. phoenicium’-related phytoplasmas (16SrIX) were identified in cowpea; ‘Ca. P. oryzae’-related phytoplasmas were identified in arecanut from North Tripura and ‘Ca. P. asteris’-related phytoplasmas were detected in Toona ciliata from Jampui Hills. This study suggests the presence of a wide genetic diversity of phytoplasmas infecting different crops and weeds in the Tripura state of India.