In this study, the impact of cropping systems on physicochemical properties of soil and microbial biomass was evaluated. Soil was collected from four cultivated fields (cropland, crop + single tree species, crop + multiple tree species and homegardens) and one uncultivated (agriculturally discarded) field and analysed. The outcome of the present study indicated that cultivated land squandered about 14% C and 5% N in 8 years of cultivation to the nearby uncultivated land. Soil microbial biomass of cultivated land with multiple tree species (C + mT) was greater than other systems and showed an appreciable seasonal variation. The microbial biomass carbon (C mic ) assorted from 166 to 266 μg g -1 and microbial biomass nitrogen (N mic ) from 11 to 41 μg g -1 . C mic contributed 1.25-1.90% of soil C and N mic 0.83-3.77% of soil N. Among cultivated land, maximum C mic and N mic were reported in C + mT system which suggested that tree plantation in cultivated land has significant positive effects on microbial biomass and other soil properties by shifting natural soil properties under the similar environmental circumstances.

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The essential oil of Salvia nubicola Wall ex Sweet. (Lamiaceae) was analyzed by GC and GC/MS. Sixty-four compounds were identified, constituting 94.0% of the oil. The oil was found rich in sesquiterpene hydrocarbons (73.3%). Germacrene D (46.2%) was the principal constituent. Oxygenated sesquiterpenes constituted 12.3% of the oil. The oil showed activity against tested bacterial and fungal strains used, and which was found comparable with the standard antibiotics (Ampicillin, Erythromycin and Clotrimazole) used for comparison.

The chemical composition of the methanol extract obtained from Araucaria cunninghamii Sweet. bark was determined by GC-MS analysis with its antioxidant and antibacterial potential, for the first time. A total of 73 compounds were identified and the extract was strongly characterised by Viridiflorene; Androstan