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Brinjal is one of the most important vegetable crops grown in India for a wide range of culinary and medicinal purposes. Many fungal and viral diseases infect the crop, but the well-known disease that causes complete yield loss is phytoplasma. Phytoplasmas in brinjal belong to the 16SrI and 16SrVI groups in India and the characteristic symptoms are yellowing, severe stunting, reduced leaf size, necrosis, reduced internodes and dispersal of flowers before maturity, causing severe yield loss. Till now, there are not many studies on the detection and characterization of phytoplasmas infecting brinjal in Tamil Nadu. Therefore, a survey was conducted in major brinjal growing districts (Thiruvallur, Coimbatore, Thiruvannamalai, Krishnagiri, Vellore, Dindigul, Pudukottai, Ramanathapuram) of Tamil Nadu to monitor the disease incidence and yield loss caused by the phytoplasmas infecting brinjal. During the survey, the disease incidence ranged from 5.0 to 95.0 per cent, with Coimbatore district recording the highest incidence of 95.0 per cent. Nested PCR testing of the symptomatic samples collected from the different districts showed that all the samples collected were positive. Sequencing results also showed that all the samples belonged to the 16SrVI group and virtual RFLP analysis of the sequences indicated that the phytoplasmas infecting brinjal in the major brinjal-growing districts of Tamil Nadu belonged to the 16SrVI-D subgroup. [ABSTRACT FROM AUTHOR]

During 2012–2014 surveys for the presence of phytoplasma diseases in Fars province (Iran), pomegranate little leaf symptoms were observed in several orchards in Khafr and Neyriz areas. Samples collected from symptomatic plants positively reacted in nested PCR assays using P1/P7 followed by R16F2n/R16R2 primer pairs producing the expected 1,250 bp DNA fragments. Real and virtual RFLP analysis showed that the sequences of phytoplasma strains from Khafr and Neyriz (KPLL and NPLL strains, respectively) were identical to each other and belong to 16SrII phytoplasma group, subgroup D. Phylogenetic analysis of the R16F2n⁄R16R2 DNA region confirmed that KPLL and NPLL phytoplasmas were enclosed in the same clade as other 16SrII-D subgroup phytoplasmas. This is the first reported occurrence of a 16SrII phytoplasma infecting pomegranate trees. [ABSTRACT FROM AUTHOR]