aPlant Biochemistry and Molecular Biology Lab, Department of Botany, University College, Thiruvananthapuram 695 034, Kerala, India
bDivision of Molecular Medicine, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Thiruvananthapuram 695 012, Kerala, India
cDepartment of Biotechnology, St. Thomas College, Palai 686 575, Kerala, India
*Corresponding author. E-mail: oprmohan@yahoo.com
Using the polymerase chain reaction (PCR) the 16S rRNA gene of phytoplasma associated with Kerala wilt disease of coconut palm (Cocos nucifera L) was amplified from infected leaf samples. Within the three universal primer pairs P1/P6, P1/P7 and P4/P7, the primer pair P4/P7 only showed an amplification of 650 bp DNA fragment. Since P4/P7 amplifies the 16S–23S intergenic spacer region of 16S rRNA gene, the PCR product 650 bp of Kerala wilt disease palm indicates the phytoplasma DNA. The amplified fragment was sequenced and deposited in Genbank data library (Accession No. AY158660). The absence of restriction sites for BclI and RsaI in 650 bp indicates phytoplasmic nature of DNA and its strain difference. A comparison of the 650 bp sequence with other phytoplasmas and its restriction profile indicates Kerala wilt disease phytoplasma as a separate 16S rRNA group in the classification of phytoplasmas. To our knowledge, this report records the first finding of the phytoplasma DNA using universal primers and its sequence analysis in coconut palms of Kerala, South India.
Kerala wilt disease, phytoplasma, PCR, 650 bp, restriction analysis
