Evaluating Rice Biodiversity and Yields of Upland Rice Landraces Grown in Shifting Cultivation in Bandarban,Bangladesh

摘要

Shifting cultivation,popularly known as jhum,is a dominant form of agriculture in the Chattogram Hill Tracts(CHT)of Bangladesh with upland rice being the major component of the system.The region is known for its rice biodiversity,which is under threat.This study was an attempt to explore the extent of rice biodiversity and variation in rice yields observing 81 randomly selected shifting cultivation plots from 26 dispersedly located mountainous villages in four sub-districts of Bandarban,one of three districts of the CHT.A total of 28 landraces of upland rice was grown in shifting cultivation.Highest number of landraces(16)was found in sub-district Thanchi.Three landraces most frequently observed were Gunda,Maemonsing and Sadabinni.Rice grain yield varied between 1.421 t ha-1 and 3.442 t ha-1 across landraces with the highest being recorded for Patobi.Landrace Dilon the lowest yield.Relative performance of landraces Kobrokbinni,Maemonsing,Monthon,Patobi and PD were superior to standard BRRI dhan83 and Gunda in relation to grain yield.Some of these landraces having wider adaptability may be released as varieties.