摘要: | The purpose of this experiment was to study the effects of low level s-triazine compounds on the protein content and amino amino acid composition of rice grain, and their influences on the activities of some enzymes involved in protein synthesis of rice. It seems that foliar application of 5 ppm simetryne at flowering stage could increase the protein content in leaf blade, and grain of Indica type cultivar Taichung (N) 1 over the control by 14.2% and 10%, respectively. Soil application of simazine at 2.8 or 5.6 mg per pot also could increase the protein content in leaf blade and grain by 13-15% and 12%, respectively. The different stimulating effects of these two s-triazines on Taichung (N) 1 by different methods may have something to do with the degree of lipid and water solubility of these compounds, or affected by the reaction of these compounds with colloid of soil clay. As a whole, these treatments increased the protein content of rice grain, could increase major amino acids such as that Aspartic acid, Glutamic acid, Methionine, Threonine, Leucine, and the total amino acid content. However, neither the protein content in grain, nor leaf blade of Japanica type cultivar Taichung 65 were affected by both foliar and soil application of s-triazines at flowering stage. Foliar applications of 1 ppm, 5ppm simazine and simetryne to 14-day-old rice seedlings could increase the activities of nitrate reductase and glutamic acid dehydrogenase on 4th and 8th days after treatment, the increasing range from 30 to 50% for NR, and 30 to 80% for GDH. The protein content of the top part of seedlings were also increase 4.5-6.5% on 6th day after treatment. Both the fresh weight and dry weight of rice plants were not affected by application of s-triazines at flowering or seedling stage. The protein content in grain and leaf blade of Taichung (N) 1 could be increased by application of s-triazines. But yield is as same as the control. So, it may have practical and economic value to increase the grain protein content of Taichung (N) 1 by using s-triazines. |