Role of Anthraquinones as a Marker of Juvenility and Maturity in Response to Adventitious Rooting of Tectona grandis

Adventitious root formation in woody plants is highly influenced by the process of physiological ageing. There are increasing efforts to identify markers for distinguishing between mature and juvenile stages of trees. However, it appears to be very little information on this aspect at the chemical and molecular levels. The aim of the work was to identify potential chemical marker of juvenile and mature state; and accomplish maximum rooting in teak (Tectona grandis Linn. f.) leafy shoot cuttings. Experiments with teak leafy shoot cuttings of three different physiological ages 30- and 15-year-old (mature); and 2-month-old (juvenile) were conducted in mist propagation system. Maturity of donor teak plants decreased rooting ability. Cuttings obtained from 2-month-old donors rooted more profusely in comparison to 15- and 30-year-old donors. Indole-3-butyric acid treatment at 4000 mg L-1 significantly increased rooting percentage and produced highest number of roots. High Performance Thin Layer Chromatography (HPTLC) analysis of anthraquinones (AQs; C14H8O2) was utilized to detect qualitative and quantitative differences in AQs in stem tissues from 2-month, 15- and 30-year-old donor plants. The HPTLC analysis showed that AQs varied from 2.8 to 18.3% in cuttings derived from 2-month-old donor plants, while the variations were 4.9 to 27.3% and 11.8 to 43.4% in those from 15- and 30-year-old donor plants, respectively. Altogether, data support that AQs could be a reliable marker for maturity vis-à-vis juvenility in teak.