This study was performed to investigate how changing the period of light and dark influences the vegetative growth and the photosynthesis of Doritaenopsis Queen Beer ‘Mantefon’. Clones of Dtps. Queen Beer ‘Mantefon’ at 4-month-old stage were grown in a closed-plant factory system with four different light/dark cycles; 06/06 h, 08/08 h, 10/10 h, and 12/12 h. Temperature and relative humidity were set at 28oC and 80%, respectively, with a photosynthetic photon flux density of 160 ± 10 μmol·m-2·s-1. Repetitive measurements showed that the leaf length and the leaf width were the longest under 12/12 h closely followed by 10/10 h. The fresh weight and the dry weight of leaves and roots were the heaviest at 10/10 h treated samples. Different CO2 uptake patterns were observed from different light/dark cycles. Under 10/10 h and 12/12 h treatments, the CO2 uptake started at early dark period. When the light/dark cycles were shortened to 06/06 h and 08/08 h, the CO2 uptake started at the middle of dark period. Total CO2 uptake amounts were the highest under 12/12 h treatment followed by 10/10 h, 06/06 h, and 08/08 h treatments. Quantitative measurements showed that the vegetative growths under 10/10 h treatment were comparable with that of 12/12 h treatment. These studies indicated that manipulating light/dark can modify the photosynthesis patterns and vegetative growth of Dtps. Queen Beer ‘Mantefon’, resulting in the reduction of the production period.

This study was carried out to gain the basic informations about botanical characteristics of plant type and properties related to table quality for developing the new colored waxy corn hybrid. Materials used were produced by our laboratory in 2007 and their major traits were evaluated fro two years(2008 to 2009) at Corn Breeding Farm of Coll. of Agri. & Life in CNU. Items surveyed were major agricultural characteristics including ear length and traits related to edible. Botanical characteristics as a plant type and ear pattern of the developed waxy corn hybrids showed large ranges among them; stem height of CNU08H-h39 among used hybrids was the highest as 235.7cm, while CNUH08-15 was the lowest. Ear height of Daehackchal Gold 1 was the highest as 83.7cm and that of CNU08H-15 was the lowest among used hybrids. Ear length of CNU08H-h121 among used hybrids was the longest as 23.1cm, while that of CNU08H-71 was the smallest as 12.7cm. Kernel sugar content of the used hybrids appeared to be 16.1 to 13.0Brix(%). Especially, CNU08H-15, CNU08H-35 and CNU08H-h39 hybrids were highly appeared as 15 above. Pericarp thickness of check hybrid, Yeonongchal, was thicker as 46.0㎛, while that of CNU08H-39 compared to other hybrids showed the thinnest as 23.0㎛. From this study, we could obtain several superior colored hybrids with thinner pericarp and high sugar contents like CNU 08-39 and CNU 08-h121 hybrids. Accordingly, these hybrids will be apply as new developed variety through confirmed trials.