Soil Seed Bank Dynamics of Weed Flora in Upland and Lowland Paddy Cultivation Areas of Far Western Nepal

For the analysis of composition of individuals of weed flora, soil samples were taken with diameter of 8cm and depth of 10cm. Soil seed bank dynamics of weed flora experiments were carried out 2004 and 2005 by incubating soil samples collected from the upland and lowland sites. Soil seed bank dynamics of weed flora were recorded by incubating soil samples collected from the two study sites. A total of 46 weed species germinated of which 18 families and 34 genera in soil samples of upland site. From lowland site soil samples, the species were just marginally lower, 43 belonging to 32 genera and 17 families. The mean total number of individuals of weeds that germinated in soil samples of upland site was 517 compared to 503 at lowland site. The highest number of weeds (186) was of the family Cyperaceae (37% of the species). The proportion of this family was 35.6% at the upland site. The dominant families were Cyperaceae, Scrophulariaceae and Poaceae in both the study sites. Of the total germinated weed species, the highest number of individuals of broad-leaved followed by sedges and grasses in both the study sites. Key words: Paddy; Weeds; Seed bank; Upland; Lowland. DOI: 10.3126/sw.v5i5.2657 Scientific World, Vol. 5, No. 5, July 2007 54-59