| Abstrak/Abstract |
Catharanthus roseus, formerly known as ornamental plant, has now been explored for its potentials as medicinal herb. One of 9 the secondary metabolites produced, namely vinblastine, has been widely used to treat some human cancers. In addition, as the relatively 10 high tolerance to drought, the plant species could produce proline, which plays important role in maintaining cellular osmotic pressure in 11 an adverse condition. This study aims to assess the profiles of vinblastine and proline in C. roseus cultivated on inceptisol under water 12 stress in combination with the applications of ZA fertilizer and rice husk biochar (RHB). A Split Plot Design was employed involving 13 three treatments, namely water stress as the main plot and the combination of ZA fertilizer and RHB as the subplot. Three levels of the 14 respective treatment were applied, namely 0, 2 and 4 days without watering; 0; 1.19 and 2.38 g/polybag of ZA fertilizer; and 0, 100 and 15 200 g/polybag of RHB. The results showed that the highest vinblastine content of 2285.25 μg/g was obtained in the combination of 4 16 days without watering, 2.38 g/polybag ZA fertilizer and 200 g/polybag RHB. Meanwhile, the highest proline content of 31.62 μmol/g 17 was found in the applications of 4 days without watering, no ZA fertilizer and 200 g/polybag RHB. The supporting agronomic 18 parameters revealed the best responses in the applications of daily watering, 2.38 g/polybag ZA fertilizer and 200 g/polybag RHB. It can 19 be concluded that the production of vinblastine increases with the higher levels of water stress, ZA fertilizer and RHB, while that of 20 proline increases with only the higher water stress and RHB. ZA fertilizer and RHB applications are shown to increase soil fertility, 21 while daily watering optimizes the growth of C. roseus. |
