Flowering, Seed Production and Natural Regeneration of Thorny Bamboo, Bambusa bambos (L.) Voss after Gregarious Flowering in Wayanad, Kerala

摘要

Bambusa bambos (L.) Voss (thorny bamboo) is a commercially improtant bamboo species grown in natural forests and cultivated in homesteads in India. It flowered gregariously in Wyanad Forest Division Kerala Southern India during 1991-92. Previous flowering occurred in 1957-62 from the same locality. Seeds matured within four months and it was predated by animals and birds. Seeds were collected from twelve selected clumps from three location viz., Chethalayam, Noolpuzha and Tholpetti for two months andthree was significant variation between seed samples from clumps in the same locality and samples collected during different period. Due to the out-break of a seed pest Udonga montana Distant, viable seeds were available only for two weeks from Chethalayam and six to eight weeks from Noolpuzha and Tholpetti. The number of seeds per Kg ranged from 58 to 82 thousand and the moisture content varied from 3.2 to 7.9 per cent in these localities. The highest seedling density was recorded in Noolpuzha. To observe the status of natural regeneration in a Wildlife Sanctuary the area was revisited after 10 years in 2003. The highest clump density was recorded from Noolpuzha. The number of clums and height of the largest culm in the clumps varied significandy among three localities. The major factors that influenced the natural regeneration of the. B. bambos were seed predators, out break of U. montana and disturbances in the form of anthropogenic and biotic interferences. Hence, protective measures to avoid such incidents are to be undertaken at the time of flowering, seed production as well as in the initial stages of regeneration to aviod depletion of resource base of the species.