Effect of harvesting time on rhizome, volatile oil and xanthorrhizol yield of four temulawak (Curcuma xanthorrhiza roxb.) Accessions

Temulawak rhizome is an important ingredient in Indonesian ‘jamu’ because of its various benefits. Rhizome, volatile oil and xanthorrhizol yield became quantity and quality indicators of temulawak. The objective of this research was to study the effect of harvesting time on rhizome, volatile oil and xanthorrhizol yield of four temulawak accessions. The experiment was conducted at Puspiptek Serpong, Tangerang in 2010. Randomized complete block design was used with two factors and three replications. The first factor was harvesting time (7, 8 and 9 months after planting), the second factor was temulawak accessions (T4, T11, Cursina 1 and Ungaran local variety). The results showed that the interaction between harvesting time and temulawak accessions affected rhizome dry weight. The highest dry weight was shown by accession T11 on 9 months (368.41 g/plant). Harvesting time affected volatile oil content, rhizome fresh weight, rhizome water content and rhizome rendemen. Volatile oil content and rhizome water content was decreasing with the increasing of harvesting time, but the rendemen was increasing. The highest volatile oil content was at 7 months (5.88%). Rhizome fresh weight was highest at 8 months (1206.3 g/plant) then decreasing at 9 months (839.6 g/plant). Accessions showed different responds in volatile oil yield, rhizome fresh weight, rhizome water content and rhizome rendemen. The highest volatile oil yield (1628.2 ml/plant), rhizome fresh weight (1494.4 g/plant), rhizome dry weight (295.16 g/plant) and rhizome water content (79.9%) were shown by T11. High water content of T11 produced low rendemen, but its dry weight was still the highest among four accessions tested. Harvesting time, temulawak accessions and their interaction were not affected xanthorrhizol content and xanthorrhizol yield.