What is the role of national gardens in conserving biodiversity-discuss

Explanation

There are four important national botanical gardens in India Viz. (1) Indian Botanical Garden Kolkata, (ii) National botanical garden in Lucknow, (iii) JNTBGRI, Trivandrum and (iv) the National Archidarium, Yercaud.
Indian botanical garden was established in 1777 by Lt. Col. Robert Kyd and was the largest and oldest among national botanical gardens. This garden has more than 15,000 species of plants. The National Botanical garden in Lucknow was established in 1948 and has about 500 species of plant, while JNTBGRI, Trivandrum was establised in 1979 and housed 4000 species of flowering plants and 300 species of non flowering plants with 69 species of Bambusetum which is considered to be the major attraction of this garden. The national Orchidarium, Yercaud was established in 1963 and maintained by the southern circle of Botanical survey of India. This garden is the treasure house of 3,000 trees and 1,800 shrubs. The major attraction of the garden is the availability of insectivorous plants.
These national gardens are centre of learnig for students, researchers for their studies on biodiversity of various plants. Besides these gardens act as conservation centre for diversity, rare and endangered species. They also offers annual list of available species and tree exchange of seeds. Hence the nation botanical gardens play a greater role in conserving plant biodivesity of our country.