The growth and physiological growth characteristics of Stevia rebaudiana SM4 and wild Stevia rebaudiana were compared. The results showed that Stevia rebaudiana SM4 had larger leaf area, higher net photosynthetic rate, higher chlorophyll content, higher protein content and higher DNA and RNA content than wild Stevia rebaudiana in the same period. After 40 days of growth, the net photosynthetic rate and protein content of wild stevia rebaudiana leaves gradually decreased, but the decline rate was slow, and the total glycoside content of stevia rebaudiana SM4 was higher than that of wild stevia rebaudiana. (***3 pages) article Keywords: Stevia rebaudiana protein photosynthetic rate Stevioside article snapshot: Yu Yirongchun _' . . ● 1. ●. ’。 . 1 (Zhejiang Agricultural University, Hangzhou = HL 3 10029) 0' 1oi The growth, physiological and biochemical characteristics of Stevia rebaudiana SM4 and wild Stevia rebaudiana were compared. The results showed that Stevia rebaudiana SM4 had a large leaf area, and the net photosynthetic rate, chlorophyll content, protein content, DNA and RNA content of leaves were significantly higher than those of wild Stevia rebaudiana in the same period. On the fourth day of growth, the net photosynthetic rate and protein content of wild Stevia rebaudiana leaves gradually decreased, while the decline of Stevia rebaudiana SM4 was slow. The total glycoside content of Stevia rebaudiana SM4 is 65438 0.5 higher than that of wild Stevia rebaudiana, in which the content of red A glycoside is increased, while the content of Sty glycoside related to gramineous weeds is slightly decreased. Li Huangken+Tang+China Library Classification $566.9; Q945— ——,, WcngX ~ oyanSunJn Zangrongchun (Department. Zhejiang Agricultural University, Hangzhou 3 10029, China) studied plant growth and physiological characteristics. Journal of Zhejiang Agricultural University, 1996 t22(5):538 ~ 540 Abstract 4 females. The yield and some physiological characteristics of dsm4 mouth and right mouth were compared. The results showed that the leaf area per plant was 4wa. shigherthanthatofconforestuare " D/Kou。 Compared with maize, the net photosynthetic rate, chlorophyll content, protein content, DNA content and nao fs4 content are always higher. Especially higher protein content and net photosynthetic rate. The stevioside content was 1.5%, which decreased slightly and increased significantly. Keywords keywords stevioside-stevia rebaudiana-stevia rebaudiana photosynthetic' protein' is a natural sweet plant of Stevia in Compositae, and its sweet component is stevioside, which mainly exists in leaves. The content of stevioside is about 65438±0O. Stevioside (Stv) and rebaudioside A (Reb-A) are two main components in Stevioside. In addition, there are several trace sweet ingredients such as glycoside C, D and E in the project funded by Zhejiang Education Commission. Stevioside is a very suitable sugar, with high sweetness (300 times of sucrose) and low calorie (] only t300 of sucrose). It has a certain therapeutic effect on obesity, hypertension and diabetes. Stevia rebaudiana is a new resource plant with great development prospect. Stevia rebaudiana was introduced into China for a short time, with few provenances, and its research and utilization started late. There are few reports on some physiological characteristics of sweet S-stage Weng Xiaoyan and other varieties, as well as the growth and physiological characteristics of stevia rebaudiana. The growth, photosynthetic characteristics, protein and nucleic acid of Stevia rebaudiana and wild Stevia rebaudiana were systematically studied. At the same time, the content and composition of stevioside were analyzed, which provided theoretical basis for cultivating stevioside varieties with high quality and high sweetness. For the determination of protein content, refer to Bradford method [determine the soluble and insoluble protein content, and add them to get the total amount; The contents of RNA and DNA were determined by Cherie method. According to the method of Fujinuma, the content of stevioside was determined by TLC scanning. The test was repeated three times. 1 Materials and Methods 2 Results and Analysis Stevioside was provided by Qiaosi Experimental Farm of Zhejiang Agricultural University, which was a wild variety with high sweetness. Samples were taken every 10 day 50 days before Stevia rebaudiana was harvested, and related physiological and biochemical indexes were determined. The net photosynthetic rate of leaves was 2. 1 with LI-6000 portable photosynthesis system. The growth characteristics of different varieties of Stevia rebaudiana are obviously different (table 1). Stevia rebaudiana uses leaves as harvesting organs. Therefore, the leaf area per plant of Stevia rebaudiana SM4 was 20.1o larger than that of wild Stevia rebaudiana, and the dry matter weight per unit area increased by 4.88. Therefore, the yield of stevia rebaudiana dry leaves was improved. Table 1 Comparison of growth characteristics and stevioside content of different stevia varieties. Physiological and biochemical characteristics of the variety 2.2. 1 Photosynthetic rate and chlorophyll content of Stevia rebaudiana SM4 are obviously different from those of wild Stevia rebaudiana (Figure 1). Firstly, the net photosynthetic rate of Stevia rebaudiana SM4 was higher than that of wild Stevia rebaudiana. Secondly, the net photosynthetic rate of wild Stevia rebaudiana SM4 and Stevia rebaudiana SM4 reached the maximum on the 40th day, and then the net photosynthetic rate of Stevia rebaudiana SM4 was higher. On the 5th, 60th, 70th and 80th day, the net photosynthetic rate was 65438 02.7, 265438 08, 46.9 and 36.6 higher than that of wild Stevia rebaudiana. It can also be seen from Figure 1 that the chlorophyll content of Stevia rebaudiana leaves reached the maximum on the 40th day of growth, and the leaf green turbulence content of Stevia rebaudiana SM4 leaves was 7. Five times higher than wild stevia rebaudiana. Oo■ Smoke *200} 100O● Ye Nie's volume. The establishment rate of clean light platform is 30405060, and the growth time is the same (days). Three ●. ● Luo Yi. Fig. 1 Changes of photoperiod rate and leaf Yao Su yield during the growth of different stevia varieties F. 1 Changes of photosynthetic products and chlorophyll content during the ideological development of stevia varieties 0 {stern &: Udiana and Journal of Zhejiang Agricultural University (Volume 22) have strong growth potential and prolonged the photosynthetic function period. 2.2.2 See Table 2 for the changes in the content of biogenic components. As can be seen from Table 2, the contents of protein, RNA and DNA in Stevia rebaudiana and Stevia rebaudiana reached the highest on the 40th day of growth, and then gradually decreased with the extension of growth period. However, during the whole growth period, the protein content of Stevia rebaudiana was always higher than that of wild varieties, especially after 40 days of growth, the protein content decreased slowly, and the protein content in the body remained at a high level. The variation law of RNA is similar to that of protein, which shows the consistency of RNA translation into protein. With the growth of Stevia rebaudiana, the DNA content of Stevia rebaudiana sM4 showed a downward trend, but the DNA content of Stevia rebaudiana SM4 was still higher than that of wild varieties. Changes in RNA and DNA content. 2.2.3 Stevioside content is significantly different from Stevioside SM4, wild Stevioside and total glycosides of its main components (Table 1).