Genetic conservation and improvement of bamboos in Northeast India

摘要

Bamboos are long-lived, evergreen plants, belonging to the family Poaceae. They are well known for their versatile uses. They are well-represented naturally in all the continents except Europe. Bamboos are very unevenly distributed in the tropics, subtropics and mild temperate regions of the world, from sea level up to an elevation as high as 4000 m (Soderstrom and Calderon, 1979). Eastern and Southern Asia are the centres of bamboo distribution. There are as many as 70 genera, and about 1200 species of bamboos, reported from different parts of the globe (Biswas, 1988). According to Sharma (1980) and Soderstrom and Ellis (1982) the total number of bamboo is represented by 75 genera and 1250 species. Almost all the species of bamboos are woody andfast growing. The herbaceous bamboos are mostly confined to the tropical and subtropical regions of South America. Most of the bamboos require warm climate, abundant mositure and fertile soil for their luxurious growth. In bamboo production, India ranksnext only to China with a production of 323000 tonnes per year (Pathak, 1989). The diversity of genetic resources of bamboo is very rich in India. The country has large reserves of bamboos covering an area of 10.03 million hectares (Sharma, 1987). This covers about 12.8 percent of the total area of forest cover in the country in different bio-climatic regions. Bahadur and Jain (1983) have reported 113 species of bamboos belonging to 20 genera distributed in India, Sharma (1980) reports nearly 136 species. Varmah & Bahadur (1980) have reported about 100 species, of which 10 species are believed to be commercially exploited, from which a revenue of Rs. 66776 million per annum is estimated to be derived.