• Journal of Bio-Environment Control
• /
• v.12 no.2
• /
• pp.101-105
• /
• 2003

This experiment was conducted to find out the effect of day length on the production of high quality plug seedlings in onion (Allium cepa L.). Two cultivars, ‘Changnyongdaego’ and‘Wolryun’, were grown to seedlings in 200-cell plug trays under 11.5, 12.5, 13.5 hours and natural day length. These seedlings were transplanted to the pot (16 cm In diameter) and grown under 16 hours day length. Number of leaves and neck diameter showed better growth in the longer than shorter day length treatments, but plant height old sheath length were retarded in the longer day length treatments. Growth such as no. of leaves, neck diameter, plant height and sheath length increased with the passage of day, but plant height and neck diameter decreased by treatment over 20 days with 13.5 hours day length. Bulbing and bulb size of onion after transplanting were enhanced in the seedlings cultured under longer day lengths. From the above results, treatment of long day length during seedling culture in plug tray can control the overgrowth and produce high quality plug seedlings.

• Horticultural Science & Technology
• /
• v.28 no.5
• /
• pp.750-756
• /
• 2010

This study was performed to investigate the role of phytohormones in the bulbing of garlic in order to assess the yield and quality. The effect on endogenous plant hormones such as gibberellin (GA) content was also examined during growth stage i.e. clove differentiation to bulbing in garlic. More than 18 gibberellins in garlic were identified with extensive gas chromatograph-mass spectrometry-selected ion monitoring (GC-MS-SIM) quantitative analysis. The results showed that GAs were biosynthesized by both non C-13 hydroxylation pathway (NCH) and early C-13 hydroxylation pathway (ECH) in garlic plant. It was also revealed that NCH pathway leading to synthesis of bioactive $GA_4$ was the more prominent GA biosynthesis pathway than ECH pathway in which bioactive $GA_1$ was synthesized. Total GAs level was gradually increased from clove differentiation to bulbing and later decreased, which portrays the active role of GA in differentiation. The biosynthesis ratio of bioactive $GA_4$ and $GA_1$ concentration was similar to that of total GAs content, which was closely related with bulb development in garlic.