Context: Currently, India’s sandalwood trees, the country’s pride — particularly of Karnataka — are facing a serious threat with the return of the destructive Sandalwood Spike Disease (SSD).
Key Points

• The recent infection has resurfaced in the aromatic tree’s natural habitats in Karnataka and Kerala.
• The natural population of sandalwood in Marayoor of Kerala and various reserve forests in Karnataka, including MM Hills, are heavily infected with SSD for which there is no cure as of now.
• Presently, there is no option but to cut down and remove the infected tree to prevent the spread of the disease, caused by phytoplasma — bacterial parasites of plant tissues — which are transmitted by insect vectors.

About Sandalwood Spike Disease

• It is an infectious disease which is caused by phytoplasma.
• Phytoplasmas are bacterial parasites of plant tissues which are transmitted by insect vectors and involved in plant-to-plant transmission.
• The disease is characterized by a huge reduction in leaf size which is also accompanied by stiffening and reduction of internode length.
• At the advanced stage of the disease, the entire shoot gives the appearance of a spike of the inflorescence.
• There is no cure as of now for the infection.
• Emergence of the disease-  The disease was first reported in Kodagu in 1899. 
• More than a million sandalwood trees were removed in the Kodagu and Mysuru region between 1903 and 1916 which prompted the Maharaja of Mysuru to announce a reward in 1907 of Rs 10,000 for anyone finding a remedy. 
• The growing stock had been reduced to 25% of its initial level between 1980 and 2000 in Karnataka.
• Following this, the International Union of Conservation of Nature declared Sandalwood as “Vulnerable” in 1998.

Importance of Sandalwood

• India has been the traditional leader of sandalwood oil production for perfumery and pharmaceuticals. As early as 1792, Tippu Sultan had declared it a ‘Royal Tree’ of Mysuru.
• Red Saunder/ Red Sandlewood- Found in southern Eastern Ghats mountain range of South India.
• This tree is valued for the rich red colour of its wood. The wood is not aromatic.
• The International Union for Conservation of Nature (IUCN) has put it under the category of near threatened from earlier endangered species in the Red List.
• It is listed in Appendix II of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES).
• The tree is not to be confused with the aromatic Santalum sandalwood trees that grow natively in South India.
• Red sandalwood has been used for making the bridge and also the neck of the Japanese musical instrument Shamisen and in furniture in China for its porch appearance.
• It is significant to note that the price of Indian sandalwood and its oil has risen significantly since 1995 at a rate of 20% annually mainly due to depletion in production.

Associated Concerns

• SSD has been one of the major causes of the decline in sandalwood production in the country for over a century.
• Each year, between 1 and 5% of sandalwood trees are lost due to the disease.
• Scientists have raised concerns that it could wipe out the entire natural population if measures are not taken to prevent its spread.
• Also, they fear that any delay in arresting the trend may result in the disease spreading to cultivated sandalwood trees.
• According to a study, the present rapid spread of the infection is largely due to restrictions on green felling in forests, which has allowed vectors to spread the disease to healthy trees.

Steps taken

• In an effort to combat the killer disease, the Institute of Wood Science and Technology (IWST), Bangalore will join hands with the Pune-based National Centre for Cell Sciences for a three-year study, initiated by the Union Ministry of AYUSH with a financial allocation of Rs. 50 lakh.
• IWST is a Centre of Excellence for Sandalwood Research and Wood Science.