Concordia Journal Home > Archives > February 14, 2008 issue >

Collaborative conservation 

By Dawn Wiseman

The Western Ghats is a hilly region that stretches 1,600 kilometers down the southwestern edge of India, about 30 to 50 kilometers inland from the Arabian Sea. Covering more than 60,000 square kilometers, the area is home to a spectacular array of flora and fauna, including Asian elephants, tigers and Nothapodytes nimmoniana (N.nimmoniana), locally known as the Stinking Tree.

As B.T. Ramesha, a PhD candidate at the University of Agricultural Sciences in Bangalore, explained, the name derives from the tree’s flowers which emit a rather “fetid smell” when in bloom.

Despite its pungent reputation, N.nimmoniana is much desired by pharmaceutical companies because it contains camptothecin (CPT), a topoisomerase inhibitor. Topoisomerase enzymes are responsible for the arrangement and rearrangement of DNA in the cell and for cell growth and replication. Inhibiting these enzymes may kill cancer cells or stop their growth.

Ramesha pointed out that in India, “local practitioners use stem bark extract [from N.nimmoniana] to treat certain malignancies.” The enzymes have also proven effective for inhibiting retroviruses such as the human immunodeficiency virus (HIV).

Since the tree’s identification as a source of CPT, it has been harvested — widely and largely illegally. There has been an estimated 20 per cent decline in its population over the last decade and the entire species is now considered endangered.

Concordia biology professor Selvadurai Dayanandan has been collaborating with professor Uma Shaanker of the University of Agricultural Sciences in Bangalore on plant genetics and biodiversity conservation for about the same period of time. One of the topics they are now pursuing, during his field research, is conservation and management strategies for N.nimmoniana. Dayanandan just returned from the Eastern Himalyan Region.

As Ramesha’s supervisor in India, Shaanker suggested he apply to the Canadian government’s Graduate Student Exchange Program (GSEP) to extend the collaboration with Concordia.

GSEP encourages Canadian universities and colleges to develop or expand their exchange programs by offering one-year scholarships worth up to $10,000 to graduate students from eligible countries. In 2008-09, Concordia will welcome six students from India, including Ramesha.

Next month, the students will travel to Montreal. For most, it will be their first trip to North America. Ramesha admitted to being a little worried about “the food and the weather.”

He is however, excited to be working with Dayanandan. “I look forward to learning new molecular biology techniques like the use of microsatellite markers in assessing population genetic variability. To derive any conservation plan for this species, first we need to understand its genetics.”

Because N.nimmoniana has been indiscriminately harvested, the remaining population is fragmented, separated by distances that are often too great to allow for effective and healthy reproduction of the species as a whole.

As Ramesha pointed out, “Reliable information on the extent of extraction has been difficult to obtain. Indiscriminate felling of the trees for short-term gains could perhaps lead to the loss of elite individuals and populations that could potentially be rich sources of camptothecin. In this study, we are planning to assess the population genetic variability of this species to help in designing the conservation strategies.”

This initial research will identify hotspots for N.nimmoniana, and help the team “identify populations of the species that are genetically depauperate,” as well as populations that need immediate attention, Ramesha explained.

With the long-term hope of building his career “in the area of bio-prospecting and conservation genetics,” Ramesha’s year at Concordia should serve him well.