품종 및 질소 시비량이 벼 종실의 단백질 함량과 조성에 미치는 영향

다국어 초록 (Multilingual Abstract)

Rice proteins are nutritional, hypoallergenic, and healthy for human consumption. Protein is one of the most important factors affecting eating and processing qualities of rice. Therefore, we examined effects of cultivar and amount of nitrogen (N) fertilizer on the content and composition of proteins in rice grains. Rice cultivars used in this study were cvs. Hopumbyeo, Baekok-chalbyeo, Baeksul-chalbyeo, Bosuk-chalbyeo, Dongjin-chalbyeo, Haepyung-chalbyeo, Hwasun-chalbyeo, Jinbu-chalbyeo, and Sangjoo-chalbyeo. The amounts of N fertilizer applied were 0, 7, 9, and 13 kg/10a. There was a considerable variation in crude protein contents, ranging from 6.6 to 9.7% and 5.7 to 8.5%, respectively, in brown and milled rice of the nine test cultivars. There was also a significant varietal variation in content of the four protein fractions. The mean contents of albumin, globulin, prolamin, and glutelin fractions of brown rice were 1.79, 0.48, 0.05, and 6.94%, respectively. Those of milled rice were 0.51, 0.31, 0.1, and 8.07%, respectively. Prolamin content was 1.4～2.5 times higher in waxy-rice than in non-waxy rice cultivars. Albumin, globulin, prolamin, and glutelin fractions for brown and milled rice were composed of seven, five, one, and five major bands, respectively, and no cultivar- or tissue-specific variations were apparent in the fractional profiles. With the increased N levels, content of crude protein was gradually increased with concomitant increase in all protein fractions. The ratios of protein fractions were similar in brown and milled rice at all N fertilizer levels. Little differences were observed in the number of major protein bands between brown and milled rice at any N level. These results suggest that N fertilizer causes quantitative but not qualitative changes in major fractions of rice proteins. Increase in the crude protein content and glutelin fraction with increased N fertilization could be beneficial for human nutrition but detrimental for general eating quality of rice.

목차 (Table of Contents)

• Abstract i
• Abstract in Korean iv
• 1. Inbtroduction 1
• 2. Materials and Methods 4
• 2.1 Chemicals 4
• 2.2 Plant Materials 4
• 2.3 Analysis of Total Rice Protein 5
• 2.4 Extraction of Rice Storage Proteins 5
• 2.5 Protein Electrophoresis 6
• 2.6 Statistical Analysis 7
• 3. Results and Discussion 8
• 3.1 Soil Chemical Properties 8
• 3.2 Varietal Variation in Protein Content and Composition 8
• 3.2.1 Protein Content 8
• 3.2.2 Composition of the Protein Fractions 12
• 3.3 Effect of Nitrogen Fertilizer Levels on Protein Content and Composition 15
• 3.3.1 Protein Content 15
• 3.3.2 Composition of the Protein Fractions 18
• 4. Summary 19
• Figures 20
• Tables 33
• References 39