Sandalwood Spike Disease (SSD)

Syllabus: General Studies Paper 3

A study has now shown that this ‘invisible’ disease, which is wiping out the sandalwood trees, can transmit through seeds of infected trees through the presence of disease-causing bacteria called Phytoplasma. 

• This phenomenon has been blamed for the spread of the SSD to commercial farms in a study by the Bengaluru-based Institute of Wood Sciences & Technology (IWST) in association with the National Centre for Cell Sciences, Pune.
• Recently, Sandalwood Spike Disease started infecting natural habitats in Karnataka and Kerala. India’s sandalwood trees, particularly of Karnataka are facing a serious threat with the return of the destructive Sandalwood Spike Disease (SSD).

Sandalwood Spike Disease (SSD)

• It is caused by phytoplasma — bacterial parasites of plant tissues — which are transmitted by insect vectors.
• 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.
• The disease was first reported in Kodagu in 1899.
• It is being classified as “vulnerable” by the International Union for Conservation of Nature in 1998.
• Presently, there is no option but to cut down and remove the infected tree to prevent the spread of the disease.
• Between 1 and 5% of sandalwood trees lost every year due to the disease.
• SSD has been one of the major causes for the decline in sandalwood production in the country for over a century.

Reasons for Spread

• 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.
• Green felling (silviculture felling) is the felling of green trees of one or more types.

Sandalwood

• Sandalwood is a class of woods from trees in the genus Santalum. The woods are heavy, yellow, and fine-grained, and, unlike many other aromatic woods. Further, they can retain their fragrance for decades. 
• 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 Sandalwood- 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.
• Sandalwood has several antibacterial, antibiotic & anti-cancer benefits amongst others. Hence, it finds its uses in pharmaceuticals, personal care & furniture.
• Sandalwood has been long associated with the Indian heritage & culture, as the country contributed 85% of the world’ sandalwood trade erstwhile. However, of late this has been declining at a fast rate.
• Globally, India & Australia are the largest growers of sandalwood. On the other hand, the biggest markets lie in the United States, China, Japan & the Indian domestic market.