Sandalwood spike disease (SSD) is fast killing sandalwood trees in Marayur, the largest natural sandalwood reserve in the world. Currently, 1,000-odd infected trees have dried up in the reserve. The disease, caused by bacterial parasites and transmitted by insects, had resulted in massive loss of sandalwood in Karnataka and Tamil Nadu, which along with Kerala contribute nearly 90% of sandalwood in the country.
M.G. Vinodkumar, Divisional Forest Officer, Marayur Sandalwood Division, told The Hindu that SSD mainly affected Reserve Number 52 and 54 near to the Chinnar Wildlife Sanctuary. He said it was first identified at Reserve Number 51 nearly 20 years ago. There are no sandalwood trees in the area now. Whether the bacteria is water-borne, air-borne or through other mediums like earth is not known, he said.
Its symptoms
The sandalwood trees dry up once affected with SSD. Leaves turn thin and yellow and no new leaves will sprout. Within four years, the tree dies. It is feared that the newly grown sandalwood trees could also be affected by SSD in slow phases.
Marayur Sandalwood Division has nearly 57,000 sandalwood trees and it is considered the best one in the country in terms of quality of sandalwood oil. Mr. Vinodkumar said seeds are collected from only the healthy trees to develop saplings so as to prevent possible disease in future.
Identified in Kodagu
The SSD was first identified in Kodagu in 1899 and it was the main reason for large-scale felling of sandalwood trees in Kodagu and Mysuru till 1916. The disease also caused widespread loss of sandalwood trees in Tamil Nadu, one of the reasons for the State-supported felling of sandalwood there. Earlier studies said that 1% to 5% of sandalwood trees are lost every year in the country due to SSD.
No remedy yet
A study conducted in the Marayur Sandalwood Division by a team of scientists led by R. Sundar Raj of the Bengaluru-based Institute of Woods Science and Technology in 2017 found SSD to be a major threat to the sandalwood reserve. Dr. Sundar Raj told The Hindu that he would visit the Marayur Sandalwood Division in May as a follow-up to the earlier survey. He said a remedy for SSD was yet to be discovered and experiments were on. Scientists of the Kerala Forest Research Institute (KFRI) had also conducted research in the Marayur Forest Division in connection with SSD.
