, to study the effect of polyethylene glycol (PEG) on the germination of kenaf seeds variety 'Jangdae', which treated with seven PEG concentrations (0%, 10%, 20%, 25%, 30%, 35% and 40%) for 24 h at 20 °C in the dark, and evaluate the effect of fungicide on surging kenaf seed germination in the field. Results showed that the critical concentration rate needed to hasten germination based on germination percentage, times to reach 50% of the final germination rate (T50) and mean no. of days to germination (MDG) is using 10% PEG. A maximum germination rate of 83.8% using hydro-priming (HP) (seed treated with HP) was observed during the first 12 h of treatment. The control's (Jangdae seed) germination increased sharply and reached a maximum germination rate of 53.2% on the 21st day in the field. After 21 d, germination of all priming treatments ranged from 13.8% to 26.3%. The palisade layer (PAL) after priming treatment was more damaged than that of the control. Also, a significant difference on the acid level between the control and PEG priming treatment (p < 0.05) was observed. It was also found out that seed modifications after priming could affect in the field. A fungicide called "Tiram" was used after priming to help kenaf seeds decrease T50 and MDG, and increase germination percentage. Results showed that application of fungicide after priming optimizes seed germination and vigor. Therefore, it is recommended to invigorate the kenaf seed before planting.

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Kenaf (Hibiscus cannabinus L.) is known as a multipurpose crop producing biomass for energy thus, the study was conducted to select the elite mutants with higher biomass produced through mutation. Obtained from the National Agricultural Genetic Resources Center (NAGRC) in Korea, the seeds of the original natural resource named IT202801 (control) were irradiated with 250 Gy gamma-ray. The agronomic performances, genetic variation and histological analysis of the elite mutant lines were investigated at M 2 generation in comparison with the control. Significant differences were observed from the previous three evaluations of the eight mutants. Nine plants, including the control and eight mutants, had little difference in the number of flowering days from July 23 to July 25. The leaf shape of the control was entire, while the leaf shape of the mutant was palmate. Of the eight lines, M 2 IT20-5 showed better performance in regard to diameter, dry weight and seed weight per plant. The random amplified polymorphic DNA (RAPD) analysis produced a genetic diversity of 72.7% within the genotypes used. A dendrogram was constructed based on the RAPD fragments. Differentiation was demonstrated between the control and kenaf mutants. Taken together, the mutant line, M 2 IT20-5, can be useful as a resource for high biomass production.