The characteristics of rice starch by sampling six rice cultivars for making rice bread were examined. Six rice varieties exhibited different level of amylose content and the ratio of chain length distribution within the amylopectin cluster. Especially, examination by colorimetric measurement of starch-I2 complex showed the maximum absorption wavelength was the highest in Goamibyeo. The X-ray diffraction patterns of starch granules showed the traditional "A" type, except in Goami 2 and Goami 3 and there was difference in crystalline of rice starch. There were significant difference in the changes of swelling power of rice starches through temperature. We could also found that the six rice cultivars had different levels of the hydrolysis rate by 5% glucoamylase. These results could suggest that properties of rice starch impact on the level of loaf formation and specific gravity of rice bread after baking.

Potato (Solanum tuberosum L.) tubers of 10, 20, 30, 40, and 50 g were planted in plug trays with vermiculite-based root medium on 10 August 2000 and grown for 15 days in a glasshouse to determine the effects of mini-tuber size on plug seedling growth and field performance of plug seedlings. For a control, common potato tubers weighing 50 g were also planted. As size of seed tubers planted increased from 10 to 50 g, seedling height decreased from 24.6 to 20.0cm while shoot number per seedling increased from 2.0 to 3.5, main stem diameter from 4.3 to 6.1mm, and fresh weight of root + top from 9.3 to 19.4 g/seedling. At 90 days after transplanting plug seedlings, the total number of tubers per plant increased from 3.62 to 4.72, average tuber weight from 62.9 to 72.8g, and total tuber yield 20.5 to 23.6 t/ha with increase in seed tuber size. Plug seedlings raised from 50g tubers produced 22% more tubers per plant and had 21 % higher＞80g tuber yield than the directly planted potatoes.