First Report of a 16SrIX Group (Pigeon Pea Witches'-Broom) Phytoplasma Associated with Sesame Phyllody in Turkey

Abstract

Sesame (Sesamum indicum L.) is an important oilseed crops widely grown in the southern regions of Turkey. Sesame seeds are primarily used in production of tahini as well as a garnish on sweets and bakery products in the country. Sesame plants with phyllody disease symptoms have increasingly been observed in the fields of Antalya province since 2007. The disease incidence in these fields was found to range from 37 to 62% (2). Infected plants display a variety of the disease symptoms such as virescence, asymptomatic shoot proliferation, infertile flower formation, reduced leaf size, and thin and weak capsule development. Total genomic DNA was extracted from samples collected from symptomatic (10 plants) and asymptomatic healthy-looking plants (10 plants) using a CTAB method and amplified with universal primers P1/P7 and R16F2n/R16R2 in direct and nested PCR, respectively (1,3). Amplifications of the DNA from the symptomatic plants yielded a product of 1.8 kb in direct and 1.2 kb in nested PCR assays. No amplification was observed in symptomless plants of the same age and collected from the same fields. Amplicons were purified, cloned in a pTZ57R/T Vector, and sequenced using a Beckman Coulter 8000 CEQ Genetic Analysis System. Four aligned 16S rDNA sequences (1,845 bp) were found to be all identical and belonging to one species. One sequence was deposited in GenBank under the accession number KC139791. A BLAST similarity search revealed that the sequence shared 99% homology with the sequences of the members of 16SrIX group phytoplasmas, ‘Brassica rapa’ phyllody phytoplasma (HM559246.1) and Iranian Almond witches'-broom phytoplasma (DQ195209.1) available in GenBank. In addition, iPhyClassifier software (4) was employed to create a virtual RFLP profile. The analysis showed that the RFLP profile of the sesame phytoplasma 16S rDNA sequence is identical (a similarity coefficient of 1.00) to the profile of the 16Sr group IX phytoplasma reference sequence (Y16389). A phylogenetic tree was also constructed using the neighbor joining plot option of the Clustal X program. The sequence clustered together with 16SrIX group phytoplasmas. To our knowledge, this is the first report of a natural infection of sesame by a new phytoplasma species from the 16SrIX group in Turkey. References: (1) D. E. Gundersen and I.-M. Lee. Phytopathol. Mediterr. 35:144, 1996. (2) C. Ikten et al. Phytopathogenic Mollicutes 1:101, 2011. (3) C. D. Smart et al. Appl. Environ. Microbiol. 62:2988, 1996. (4) Y. Zhao et al. Int. J. Syst. Evol. Microbiol. 59:2582, 2009.

Molecular detection of phytoplasma from phyllody infected sesame and its vector orosius albicinctus distant

“…The results clearly revealed that the sesame phyllody disease was caused by phytoplasma and it is transmitted only by leafhopper, Orosius albicinctus and the stem of symptomless branch of infected plant also harbor phytoplasma. Similar results were also obtained by Al-Sakeiti et al (2005), Akhtar et al (2009) and Catal et al (2013) in different places by using same primer pairs from the infected sesame plants. However, Sertkaya et al (2007) detect phytoplasma from both infected plants and its vector Orosius orientalis (Matsumura) by using the universal phytoplasma primer pair P1/P7 in direct PCR followed by primer pair R16F2n/R16R2 in nested PCR in Turkey.…”

Association of two groups of phytoplasma with various symptoms in some wooden and herbaceous plants

“…Sesame plants affected by phytoplasma showed symptoms of floral virescence, phyllody, stem fasciation, shortened internodes and cracking of seed capsules (Figure j). Sesame phyllody has been reported to be caused by different groups of phytoplasma, that is group 16SrI in India (Khan, Raj, & Snehi, ), Myanmar (Win, Back, & Jung, ) and South Korea (Lee et al., ); group 16SrII in India (Pamei & Makandar, ), Iran (Esmailzadeh‐Hosseini, Mirzaie, Jafari‐Nodooshan, & Rahimian, ), Oman (Al‐Sakeiti, Al‐Subhi, Al‐Saady, & Deadman, ), Pakistan (Akhtar et al., ), Taiwann (Tseng, Deng, Chang, Huang, & Jan, ), Thailand (Martini et al., ) and Turkey (Ikten et al., ); group 16SrVI in Turkey (Sertkaya, Martini, Musetti, & Osler, ); group 16SrIX in Iran (Salehi, Heydarnejad, & Izadpanah, ) and Turkey (Catal, Ikten, Yol, Ustun, & Uzun, ); and subgroup 16SrIX–C in Turkey (Ikten et al., ).…”

“…in Iran (Salehi, Heydarnejad, & Izadpanah, 2005) and Turkey (Catal, Ikten, Yol, Ustun, & Uzun, 2013); and subgroup 16SrIX-C in Turkey (Ikten et al, 2014).…”

Multiplex Real-Time qPCR Assay for Simultaneous and Sensitive Detection of Phytoplasmas in Sesame Plants and Insect Vectors

“…The probes 16SrII and 16SrIX were designed from the sequences between these primer pairs for specific detection of 16Sr group II and group IX phytoplasmas, respectively, in TaqMan ® qPCR assay. Representative sequences of 16Sr groups I through XIV [ 47 , 48 , 49 ] ( S1 Fig ) including sesame phyllody 16Sr groups II and IX [ 39 , 40 ] were aligned to design the primer and probes ( Fig 1 ). The sequences of all phytoplasma groups available in the National Center for Biotechnology Information (NCBI) GenBank database were also included in the alignments.…”

“…Sesame phyllody, an economically important disease of sesame plants, is a serious threat in regions where peanut witches’ broom (16SrII) [ 9 , 12 , 38 , 39 ], pigeon pea witches’ broom (16SrIX) [ 40 ], aster yellows (16SrI) [ 41 , 42 ], and clover proliferation (16SrVI) [ 14 ] phytoplasmas are present. Although four different phytoplasma groups have been reported in sesame so far, the majority (approximately 77%) of identified sesame phytoplasmas have been known to belong to the 16SrII and 16SrIX groups [ 43 ].…”