A novel approach for detection of sandal spike infection in Santalum album

Santalum album, known as east Indian sandalwood, is an economically important tree species for its valuable heartwood and essential oil. One of the most common phytoplasma infection is the sandal spike disease (SSD), associated with spike-like symptoms. In this study, genomic DNA was extracted from symptomless and SSD infected sandalwood leaves. Phytoplasma detection was done by nested PCR, using two sets of universal 16S rRNA gene primers P1/P7 and R16F2n/R16R2, and by a single step PCR using sandal spike specific primer along with an internal control primer set. Expected amplicons of about 1.8 kb and 1.2 kb, respectively, were visualized from infected samples with nested PCR. With the single step PCR, amplicons of 300 bp corresponding to the internal control were observed in all the sandalwood samples, and amplicons of 500 bp were obtained only from a number of symptomatic samples.