Growth of and secondary metabolite production in sambong (Blumea balsamifera) as influenced by compost and nitrogen

The study evaluated the growth of and secondary production in the medicinal plant, Sambong, Blumea balsamifera (L.)DC., as influenced by compost medium (30%) and 60% residential waste compost (RWC) and municipal waste compost (MWC) and nitrogen (N) levels (0, 5 and 10 g ammonium sulfate (AS)) in the garden soil (GS) medium. Incorporation of different kinds and levels of compost alone in the GS medium significantly increased shoot-root ratio of sambong; however plant height, root length and root fresh weight decreased, which were observed in 60% level of both compost. Interaction effect of compost and N greatly affected node number, leaf production and fresh and dry weights of all plant organs except root fresh weight. Significant differences between RWC and MWC were only observed in node production and leaf fresh weight of the plant, where the values were lower on 60% RWC with 10 g AS compared with 60% MWC + 10g AS. Essential oil and flavanoid contents of sambong, which ranged from 0.14 to 0.27 and 5.43 to 12.53%, respectively, were influenced mainly by compost or by N alone; however, only flavanoid content responded positively to the treatments by increasing as much as 32% with the addition of compost and 22% with the application of N. No significant difference between RWC and MWC was observed for these parameters. Flavanoid yield (0.92 to 4.41 g/plt) was influenced by the interaction effect of compost and N in the media. The addition of N or compost to the GS medium increased the flavanoid yield by more than twice the yield of plants grown in 30% RWC only. Differences between RWC and MWC compost were only significant in media with 60% compost + 10g AS. On the other hand, alkaloid content (1.87 to 5.93%), alkaloid yield (0.24 to 1.72 g/plt) and essential oil yield (0.028 to 0.065 mL/plt) were not influenced by compost and N.