Hydroculture flowers are an important form of soilless flower cultivation. Hydroponic flowers are substrate-free nutrient solution cultivation. They are cleaner and more environmentally friendly than ordinary soilless flowers. They are elegant in style and highly ornamental. However, The oxygen content of substrate-based hydroponics, especially deep flow hydroponics, is quite low and often cannot meet the needs of crop roots, resulting in root rot and poor growth. In order to solve this problem, horticultural technicians from various countries have taken many measures, such as using closed-loop flow of nutrient solution to oxygenate the water in all directions. Although these technical measures have certain effects, it is very difficult to achieve stable and irregular production of many varieties of flowers in hydroponics. Currently, only a few varieties of flowers such as hyacinths and tulips in the Netherlands have achieved commercial hydroponics in the world. Researchers at Northeastern University in my country adopted cross-disciplinary science and technology, comprehensively applied plant physiology, plant nutrition and mechatronics technology, and learned from the successful experience of soilless cultivation technology at home and abroad. After 8 years of research, they finally successfully developed a flower factory. The soilless and vegetative propagation method better solves the problem of inducing flowers grown in soil into flowers grown in water. In November 2003, this technology was officially awarded an invention patent by the State Intellectual Property Office. At present, this patented technology of factory-based hydroponic flowers has been implemented in Shenzhen and other places. Using this technology, more than 500 varieties of hydroponic flowers in 9 series have been successfully cultivated, including 32 species of bromeliad flowers and 5 species of flamingo flowers. There are 5 species of orchid flowers, 10 species of ornamental ferns, 8 species of Calathea flowers, 290 species of foliage plants, 52 species of cacti and succulent flowers, and 9 species of fruit-bearing flowers such as strawberries and raspberries.
Technical Points
The patented technology of factory-based hydroponic flower cultivation is based on deep liquid flow hydroponic technology. The deep liquid flow hydroponic technology is concerned with the preparation of nutrient solution, oxygenation scheme, and water body quality. Important improvements have been made in areas such as disinfection and handling.
Nutrient solution preparation Regarding the preparation of nutrient solution, Table 1 gives the nutrition of six commonly used hydroponic flower plant categories: foliage, flower, fruit, flamingos, orchids, ferns, etc. The formula of the liquid is comprehensive in nutrition, reasonable in proportion and highly targeted. In addition to a mixture of large amounts of elements N, P, and K, medium amounts of elements Ca, Mg, and Fe, and trace elements such as Mn, Zn, B, Cu, and Mo, the formula also contains hydroponic rooting inducers and aquatic inducers. Hydroponic rooting inducer is a new growth regulator that promotes plant rooting under hydroponic conditions. Aquatic inducer is a regulator containing adenosine triphosphate that guides plants to adapt to the hydroponic environment. It can promote the movement of inorganic ions in the nutrient solution against the electrochemical potential gradient, that is, it increases the plant's active absorption of nutrients and active transfer in the body. Although the dosage of these two regulators is not large, they do play an important role in ensuring the normal growth and development of hydroponic flower plants, especially in the early stages, and can significantly improve the survival rate of hydroponic plants.
Aeration Technology In order to solve the problem of low oxygen content in deep flow hydroponics, scientific researchers have developed an oxygenation technology that combines magnetic physical oxygenation, chemical oxygenation and mechanical oxygenation (see National Invention The patent "A Method for Manufacturing Oxygen-Rich Drinking Water", patent number 00110622.8) allows the oxygen content in the water to be adjusted within the range of 5~10 mg/L as needed, which not only meets the growth needs of plants, but also reduces costs. , so that a variety of plants that were originally difficult to grow in water can be hydroponically cultivated in factory batches.
Water temperature control Regarding the temperature of the greenhouse, for hydroponics, it is not only necessary to control the temperature of the greenhouse, but also pay attention to the control of the water temperature, that is, the temperature of the nutrient solution (see Table 2). Control the temperature within the physiological temperature range of the plant roots. It can promote the effective absorption of various nutrients by hydroponic flower plants, thereby promoting the physiological metabolism and growth and development of plants. In order to control the water temperature, the nutrient solution culture tank is generally built about 100~200mm below the ground. In summer, combined with the greenhouse fan and water curtain cooling system, the room temperature can generally be reduced to 30°C when the outdoor temperature is 35°C. ℃ below, and the water temperature in the culture pool is around 23 ℃ ~ 27 ℃, which is beneficial to the safety of plants over the summer; in winter, the water temperature in the pool below the ground level can be 3 ℃ ~ 5 ℃ higher than the greenhouse temperature, which reduces Fluctuations in energy consumption and temperature. For northern greenhouses heated in winter, heating hydroponic pools through pipes is also a feasible solution to reduce energy consumption and temperature fluctuations, which is especially important for the production of hydroponic New Year flowers.
Water and fertilizer leakage Since hydroponic flowers are cultivated in a non-leakable culture tank, there is no leakage problem of water and fertilizer, so it is an efficient water- and fertilizer-saving cultivation method.
The nutrient solution should be replenished and adjusted according to consumption every week, so that each pool of nutrient solution can be used continuously for 2 to 3 seasons. It is estimated that hydroponics can save 65% of water and about 40% of fertilizers compared to soil culture.
pH adjustment Regarding the pH adjustment of the nutrient solution, the suitable pH value for most flowers is between 5.8 and 7.0. The water quality in most places in the south is soft, so it is easy to do. For northern hard water areas, it is only necessary to regularly add H3PO4 or H2SO4 (added by dilution) to easily control the pH value. Therefore, these areas (such as Beijing) can also produce very high-quality hydroponic flowers.
Hydroponics technology is the process of inducing the formation of aquatic root systems of plants and normal growth and development in nutrient solutions, so the formation and growth of aquatic roots is the core of this technology.
First of all, different plants have different difficulty in forming aquatic roots. Herbaceous plants are fast and easy, woody plants are slow and difficult. Plants with fast growth speed and large intercellular spaces are easy to form. Plants with a slow growth speed have tightly arranged cells. Difficult, it is easy for moist medium terrestrial plants that like shade, such as Araceae plants, and difficult for drought-tolerant terrestrial plants that like sun, such as peach trees. Different plants have different aquatic root forms, but they are regularly similar. Compared with terrestrial roots, aquatic roots are mostly fibrous roots with few or degraded root hairs. At this time, the water environment causes physiological changes in plants.
The creation of a suitable water environment is the focus of our technology. Only in a suitable water environment can the continuous formation and development of aquatic roots be promoted. For example, dissolved oxygen in water is a necessary condition for root respiration. Once Root formation in hypoxic water will be inhibited and may even turn brown and rot. Therefore, during the mutagenesis process, computerized real-time detection and control of oxygen is required.
In addition, suitable water temperature and suitable nutrient solution concentration and water level will affect the cultivation of water roots. These are all controlled by computers. These technologies are the core of the technology for realizing hydroponics of all plants. , it is difficult to realize water root culture without computer control, especially the culture of mutagenized plants.
Aquatic mutagenesis technology of plants
Aquatic mutagenesis technology of plants is to use modern physical technology, computer technology, control technology and biotechnology and other comprehensive technical measures to physiologically conduct physiological changes on plant roots. , biochemistry, and mutagenesis, a technology that changes the organizational structure and physiological properties of plant roots, making them highly adaptable to the water environment, and inducing aquatic roots that are fully suitable for growth in the water environment.
The difference between aquatic roots and soil roots
Aquatic roots: thin, white in color (some plants are brown), no root hairs, thin walls, and ventilated tissue;
Soil-grown roots: thick, hard, dark in color, with root hairs, thick walls, tight tissue and degenerated ventilation tissue