Four-year research on irradiated plants yields results

Study on 190 plants being taken up on Mangalagangotri campus of Mangalore University

Holigarna arnottiana (Hulgeri, left) and Flacourtia montana Graham (Hennu sampige, right) are among the saplings grown from irradiated seeds planted on Mangalore University campus (above).— Photos: H.S. Manjunath

A garden of 190 plants of the Western Ghats tree species grown from irradiated seeds (exposed to Gamma rays) has come up on the Mangalagangotri campus of Mangalore University. It boasts of plants of six species endemic to the Western Ghats, planted three months ago.

It was the result of a four-year research project on ‘radiation effect on forest tree species’ by the Department of Applied Botany at the university under a Rs. 65-lakh project granted from the Board of Research in Nuclear Sciences (BRNS) under the Department of Atomic Energy. It is said to be the first such study on forest species in the country.

K.R. Chandrashekar, professor, Department of Applied Botany and Principal Investigator of the project, said that seeds of 14 tree species of the Western Ghats belonging to 10 families were irradiated.

The purpose was to evaluate the impact on the germination physiology and biochemical constituents of the seeds. Irradiation has led to faster germination and faster growth with vigour in case of three species.

Of the 14 species, six species were endemic to the Western Ghats, two belonged to the endangered category, two were threatened and four were wild medicinal plants.

The samples were collected from their wild habitat and subjected to Gamma irradiation using the doses ranging from 25-300 Grays (a unit for measuring absorbed radiation).

He said the forest plants have been classified for the first time on the basis of their response to Gamma radiation as tolerant, moderately sensitive and sensitive species.

Tolerant plants can withstand certain doses of radiation and also show faster germination and faster growth. For example, dormant wild species such as  Canarium strictum (dhoopa),  Terminalia chebula (alale) and  Terminalia arjuna (arjuna).  

The university will, in future, study whether irradiation has changed the medicinal properties of the plants.

The BRNS has given “in-principle approval” to sanction Rs. 35 lakh for the study. Additionally, more wild species endemic to Western Ghats will be taken up for seed irradiation.