MOLECULAR IDENTIFICATION OF ‘CANDIDATUS PHYTOPLASMA ASTERIS’ 16SrIB ASSOCIATED WITH THE LITTLE LEAF DISEASE OF POTATO IN INDIA
A.K. Tiwari, M.S. Khan, A. Iqbal, S.C. Chun, M. Priya
Potato (Solanum tuberosum L.) is a widely cultivated and commercially important vegetable crop in India where it is cultivated in an area of about 1.34 million ha with a total production of about 24.7 million tons. Phytoplasma diseases of potato have been reported from several parts of the world as associated with organisms belonging to different 16Sr DNA group/subgroups. In December, 2011, little leaf disease symptoms were observed in potato crops grown in the Kushinagar district of Uttar Pradesh (India). Phytoplasmas were detected by PCR using P1/P7 primers (Deng and Hiruki, 1991; Schneider et al., 1995) which yilded amplicons ca. 1.8 kb in size only from four symptomatic samples. All four amplicons were directly sequenced from both ends and the sequence was deposited in GenBank under the accession No. KC312703. The little leaf potato phytoplasma isolate shared high 16S rDNA sequence identity (99%) with several isolates of Candidatus Phytoplasma asteris (16SrI group) from different parts of the world. Virtual PCR analysis using the web tool iPhyClassifier (Zhao et al., 1999) assigned the isolate to subgroup 16SrI-B. A number of crop and non-crop species have been reported to be infected by Ca. P. asteris in India (Raj et al., 2011). To the best of our knowledge, this is the first report of the occurrence of Ca. P. asteris (16SrI-B) in association with the little leaf disease of potato in India.