KARAKTERISASI FISIOLOGI BENIH DAN PERTUMBUHAN TANAMAN ROSELA (Hibiscus sabdariffa L.) KOMERSIAL

Abstract

Roselle flower petals are plant organs that are popularly used as herbal drinks and natural dyes. As a raw material for herbal medicine, dried roselle flower petals contain vitamin C and antioxidants. The primary pigment of hibiscine was identified as daphniphylline, which is used to treat hypertension, pyrexia, and liver damage. To obtain high quality herbal raw materials, it is necessary to use characterized seeds sources. In addition, information on the tolerance of roselle plants to abiotic environmental stresses is also needed to develop roselle cultivation on marginal land. Seed physiology studies by stress induction at seed level, and the growth of roselle plants from commercial germplasm were carried out. The aim of this study was to determine the best method for breaking seed dormancy, tolerance level to stimulated abiotic stress on seeds, and to determine plant growth character in the field. Based on the rapid test, the viability of the seeds used was 98%, whilst significant different in breaking the dormancy in terms of vigor index character with the highest index value obtained by immersion in water at 50oC for 10 minutes and 250 ppm GA3 (85.33%). The dormancy of roselle seed breaking could be carried out chemically (250 ppm GA3 and 0.3% KNO3) or physically (wound, hot and cold water). There were significant differences in the characters of hypocotyl length, root length, and wet weight of sprouts depending on the dormancy seed breaking treatments. The results of the abiotic stress test on roselle seeds sprouts showed significant differences on the germination rate, hypocotyl length, and root length. Tested roselle seeds were tolerant to Al3+ and NaCl stresses that are potential to be developed in acid soil due to aluminum and in saline soil. Based on the results of field observations, in general, each individual plant had different growth character and yield. The results of the principal component analysis showed that the six observed characters i.e plant height, branch number, stem diameter, leaves number, early fruit bolls number and fresh fruit weight contributed to the total variability. Based on the total fresh fruit weight, ten plants were then selected for further study.