The increased intra-varietal diversity has been considered as coping mechanism against unpredictable environmental factors in crop production. Relatively the risk of crop failure is minimum in landraces than in modern variety mainly because of homogenous population in modern variety. The diversity was estimated and compared between landrace and modern variety of rice and common buckwheat in both quantitative and qualitative traits. Three landraces and three modern varieties of rice were used as self-pollinated crop and experiment was conducted in Jumla. Common buckwheat was used as cross pollinated crop in Kabre consisted of nine landraces and one modern variety. These two experiments were unreplicated and variation was measured at population level. Standard deviation, coefficient of variation and Shannon’ diversity index were estimated and variation between landraces and modern varieties was tested using F-test. Dendogram was drawn considering all observed traits for both the crops. In case of rice, variation was higher in landraces than in modern varieties for most of the traits. Variation for majority of the traits was also higher in landraces than in modern varieties of common buckwheat. This higher level of intra-varietal diversity in landraces of both crops might be the major phenomenon to have increased capacity to cope with different environmental stresses. The level of variation in both landraces and modern varieties is trait specific, in some traits, landraces showed higher intra-varietal diversity. The higher level of intra-varietal diversity should be considered for resilient production system and favorable policy environment should be created to promote the use of such diversity.
Keywords: Cluster analysis, diversity index, landrace, modern variety, variation