What is Sandalwood Spike Disease which is Threatening Sandalwood Forests in India?

India’s sandalwood trees are facing a serious threat from the destructive disease called Sandalwood Spike Disease (SSD). The infection has remerged in the natural habitats of sandalwood in Kerala and Karnataka and Kerala.

Key Facts

  • As per the report, the sandalwood trees in Marymoor forests of Kerala and several other forest regions in Karnataka are heavily infected with this disease.
  • This disease is caused by bacterial parasites which are transmitted by insect vectors.
  • The report says, cutting down the tree is the only option left as of now in order to prevent the spread of the disease.
  • Reports highlight that, around 1% to 5% of sandalwood trees are lost every year in India as a result of this disease. The disease could also wipe out the entire population if timely measures are not taken to prevent its spread.

Sandalwood Spike Disease (SSD)

  • Sandalwood is a semi-root parasitic tree which is the source of the East Indian sandalwood and oil. In the tree, the Spike disease is caused by phytoplasma.
  • The disease is characterized by huge reduction in leaf size which is also accompanied by stiffening and reduction of internode length.
  • At the advanced stage of the disease, entire shoot gives the appearance of a spike inflorescence.
  • Spiked trees usually die within 1–2 years after the visible symptoms.
  • This disease was first reported in 1899 in Kodagu. In past, between 1903 and 1916 million of sandalwood trees were cut down in Mysuru region due to the disease.
  • Since there was no remedy, the Maharaja of Mysuru announced a reward of Rs 10,000 for those who find a remedy for the disease.
  • As the time proceed impact of the disease also increased. In between 1980 and 2000 the number of sandalwood trees in Karnataka reduced by 25% of usual growing stock.
  • Following this, the International Union of Conservation of Nature to declare Sandalwood as “Vulnerable” in 1998.

Pathogen- sandal spike phytoplasma

The pathogen, sandal spike phytoplasma, was first detected in 1969 by electron microscopy. These are the pleomorphic and fragile organisms that occupy small areas within the sieve tubes (phloem) of the host plants. The organism of the phytoplasma disease has not been isolated and cultivated in vitro. This is the biggest obstacle that limit the research on the disease.

Recent Steps by Government

Currently, the spread of the infection is due to restrictions on green felling in forests. It has allowed vectors to spread the disease to healthy trees. Reason being this,  production of sandalwood in India has reduced from 4,000 tonnes in 1930s to 300 tonnes. To combat the disease, Institute of Wood Science and Technology (IWST) has joined hands with the Pune-based National Centre for Cell Sciences for a three-year study. This has been initiated by the Union Ministry of AYUSH. Total fund allocation for the initiative is ₹50 lakh.

History

Tipu Sultan also declared Sandalwood tree as the “Royal Tree of Mysuru” in 1792. Thus, India has been a traditional leader in sandalwood production. India has been exporting sandalwood oil since 18th century.