"Funky Sweets" - Stevia plant non-test tube efficient fast-growing technology fast-growing stevia

Stevia rebaudiana (Bertoni) Hems, English name: sugar stevia leaf, aliases: stevia, sugar grass, sweet grass. It is native to Paraguay and Brazil in South America. Introduced in China in the early 1980s, it is a new type of sugar source plant. So far, stevia has been introduced in 27 provinces and regions such as Beijing, Hebei, Shandong, Anhui, Heilongjiang, Shaanxi, Jiangsu, Fujian, Hunan and Yunnan, and currently has large-scale planting bases in Heilongjiang, Anhui, Shandong Jining and other places.

Stevia is a dicotyledonous plant, a perennial herb of the Asteraceae family. The height of the plant is 90 to 150 cm, the base is lignified, the stem thickness is 0.8 to 1.2 cm, the primary branch is 30 to 50, and the secondary branch is 90 to 160; the leaves are opposite, oval, papery, the leaf surface is rough, and the annual single plant has 400 to 700 leaves, up to 1200 pieces. Stevia leaves contain steviol glycosides, stevia disaccharides, stevia glycosides A and steviol B, stevia A, stevia B, steviasideS C, D, E, esmonasin A, 6-O-acetyl Azelanol, Zeelanol, ozilanin, the sweetness is about 300 times that of sugar, and the calories are only 1/300 of that of white sugar. Stevia is stress-resistant, has few pests and diseases, and has wide adaptability, and can be planted in both north and south China. The area south of the Yangtze River can generally overwinter naturally, and the north can use cellars to protect the roots for wintering, and transplant and colonize in the coming year. It is cultivated in a fertile, moist and sandy loam soil that is easy to drain and irrigate. Stevia has a shallow root system, is resistant to moisture and drought, prefers to grow in a warm and humid environment, but can also tolerate low temperatures of -5 °C, and is most suitable for stem and leaf growth at temperatures of 20-30 °C. Stevia is a short-day plant with a strong sensitivity to light, with a critical day length of 12 hours, so it is cultivated in low latitudes to flower earlier, and when buds appear in plants, the leaves contain the highest inulin glycosides. The growth period of stevia is about 140 days, and the planting season generally produces 1000 to 1500 kg of fresh leaves and 180 to 230 kg of dried leaves, and the highest yield can reach 300 kg in The sea forest of Heilongjiang. According to reports, due to the high density and fertility and water industry in Japan, the yield of dry leaves per mu can reach up to 700 kg.

Stevia can tolerate low temperatures of -5 °C and can be planted in both the north and south of China. The cultivation technology of northern stevia mainly includes three major links: seedling raising, transplanting and harvesting. Seedlings are generally used in plastic greenhouses to keep insulation seedlings, 10m2 seedbed sowing stevia seeds 75~100g, seedbed stevia seedling density of 1000~1200 plants per square meter. The temperature in the shed is controlled at 15 ~ 25 ° C, and it is necessary to ventilate in time above 28 ° C. The seedbed should be watered frequently and kept moist, and the seedling age should be 40 to 50 days; the determination of the transplanting period should be suitable for the transplanting period when the average daily temperature is stable at 12 to 15 °C, and the number of transplanted seedlings per mu is 1.0 to 15,000 plants, and the row spacing of 65 to 70cm is better. The transplanting method is: manually or mechanically ditching the ridge, watering enough, planting seedlings covered with soil and sealing. Harvest period: Occurs during the budding period with the highest sugar content, and the northern stevia harvest period is generally completed before the frost comes at the end of September. In general, stevia is highly resistant to stress, has few pests and diseases, has wide adaptability, and is less difficult to plant.

For a long time, people have been accustomed to using sugar cane, sugar beets and other plants to extract daily use of sugar, brown sugar, glucose and so on. These sugars are nutritious, but at the same time they are also high in calories, and eating too much will have a certain impact on health. For example: children eat too much is easy to cause caries, adults eat too much is easy to cause obesity, arteriosclerosis, diabetics should strictly control the intake of these sugars. Later, people used synthetic methods to obtain saccharin that was 300-500 times sweeter than sugar and did not contain calories, which was used to make up for the lack of sugar and so on. However, studies have found that saccharin also has adverse effects on the human body, long-term consumption of saccharin may cause cancer, in the short term, a large amount of saccharin consumption may also directly lead to poisoning. Since the 1960s, a sweetener called xylitol has been used in food. Xylitol is a normal intermediate in the body's sugar metabolism, with a sweetness similar to sucrose, but the calorie content is only 40% of that of ordinary edible sugars. Since it does not require insulin in the human body and can be absorbed by cells, xylitol is used as a sweetener, nutritional supplement and adjuvant therapy for diabetics, in addition to xylitol also has a certain effect on preventing caries. However, recent studies have found that xylitol cannot replace glucose to correct metabolic disorders, nor can it reduce blood sugar, urine glucose, and improve clinical symptoms. Consuming too much xylitol can also cause blood sugar levels to rise, and there may be side effects of diarrhea. Under such a premise, the excavation and utilization of stevia has brought good news to mankind. Stevia contains a high content of inulin, especially the content of inulin in the leaves is about 12%. Stevia is 300 times sweeter than ordinary sucrose and the calorie content is only 1/300 of sucrose, so eating stevia will not make people fat, especially suitable for obese patients and diabetics. Therefore, stevia is currently an excellent sugar cash crop. Long-term use of stevia boiled water to drink, but also lower blood pressure, promote metabolism and strengthen the body effect; as a pickling agent added to soy sauce, soy sauce melon and other sauces, has a preservative effect; stevia has begun to replace saccharin, widely used in the food industry, known as "fashionable sweets".

The excavation and utilization of stevia is late, in the 80s due to the processing link can not keep up, the circulation is not smooth, the development speed of stevia is slow, in recent years with the maturity of processing technology its development rate began to increase, stevia has now become China's sugar cane, sugar beet after the development of the third sugar source. Stevia extracted from stevia, known as "natural saccharin", is widely used in the beverage, confectionery, pastry and other food industries, and its cost is more than 50% lower than that of sucrose, becoming the leader in the current green food. China's current sugar consumption per capita (year) is less than 7kg, from europe and the United States per capita 40 ~ 60kg gap is very large, with the improvement of the living standards of Chinese, the consumption of sugar has been from the simple demand for sweetness is developing in the direction of nutrition, health care, medical health and other multi-functional directions, stevia has a unique advantage for people have great attraction. By 2005, the worldwide market demand for stevia stevia has increased to more than 2 million tons, which shows that stevia production has great prospects and broad prospects. In the past two years, the overall market of stevia in China has begun to show a situation of short supply, and many stevia processing manufacturers have not had enough raw materials to expand production. According to the survey, the price of dried leaves of stevia in 2006 was 6-9 yuan / kg, and in 2007, the price of dried leaves of stevia rose to 12 yuan / kg. Under normal circumstances, an acre of land can produce about 200 kilograms of dry leaves per season, and areas with a suitable environment can harvest 2-3 seasons a year, so there are at least thousands of yuan of economic benefits per mu of land. Under the appropriate planting management conditions, its yield can reach up to 700 kg, and the economic benefits per mu of land can reach more than 10,000 yuan in this case, which shows the potential huge market prospects of stevia.

Traditional propagation methods of stevia include cuttings, striping, splitting and seeding. Because stevia is originally wild, but also a heterophyll pollinated plant, after years of introduction and domestication, the offspring are widely separated, the variation range is very large, mixed strains include large leaves, small leaves, thick leaves, thin leaves, late ripening, early ripening, disease resistance, disease resistance, drought resistance, drought resistance and other types. If seed seedlings are used, on the one hand, their young plant traits cannot be stably protected; on the other hand, the seedling formation rate of stevia seeds is low, and the germination rate is only 60%-70% in the suitable environment, while the final seedling rate is generally about 30%, and now the price of stevia seeds is higher and the number is limited, so it is difficult to use seeds to carry out a large number of stevia breeding in the short term. For breeding methods such as cuttings, stripeing, and splitting, since the planting of stevia is ultimately to harvest its leaves and stem segments, the use of these methods of propagation will consume a large number of stevia raw materials, so it is not suitable for large-scale production. In contrast, in the large-scale cultivation of stevia, the use of Cologne fast propagation technology invented by researcher Li Changxiao, that is, plant non-test tube efficient fast propagation technology (TERNPC) will undoubtedly accelerate the industrialization process of stevia. The fast propagation technology of stevia has been successfully developed, and one leaf of stevia is cultured, and under suitable conditions, it grows root in 5 days and can become a seedling in about 20 days. Traditional propagation methods are very slow to quickly establish tens of thousands of acres of stevia raw material base, production costs are higher, and in the current stevia market, an early preemption represents higher profits. Li Changxiao's invention of the plant Cologne fast breeding technology can meet people's demand for large-scale industrial production of stevia for high-quality seedlings, which can save a lot of construction time and production costs. If investors invest 20 million yuan to plant stevia, they can get a high return of up to 100 million yuan. For stevia, compared with the cologne fast propagation technology and tissue culture propagation technology, it can be efficiently propagated according to the geometric progression, fast speed, high seedling growth rate, early harvest after seedling cultivation, and high yield; it also has the advantages of low input cost and industrialization, which is suitable for the rapid large-scale establishment of raw material bases.