Plant factories are an advanced stage in the development of facility horticulture. They are subversive farming and land-use methods and have important applications for solving agricultural resources and environmental problems in the 21st century. The LED light source is the preferred light source for plant factories. Many specific characteristics make it have incomparable advantages in the field of optoelectronics and modern agriculture. It is rapidly entering the level of commercial R&D and application, and its industrial prospects are attractive. The article summarizes the development trends of LED grow light and its plant factories and explores the key research and development directions for plant factories and the key application directions of LEDs.
New developments in LED plant factories
LED has been in existence for decades, and it has been used in plant lighting for more than 10 years. LED lighting has played a great role in the development and progress of mankind. The development of plant factory technology has promoted LED to enter the field of plant lights. Due to the advantages of grow light LED, it has developed more and more rapidly in the field of plant lights. Looking at the equipment and development of plant factories, there are the following trends.
Development trends of three-dimensional multi-layer soilless culture technology
The three-dimensional multi-layer soilless cultivation technology and equipment is the essential equipment necessary for the artificial light plant factory, and it is also the technical equipment that the sunlight plant factory needs to develop urgently. The development is rapid, and the three-dimensional multi-layer soilless cultivation technology and cultivation technology based on this have been developed. At present, only outdoor leafy vegetables are produced. At present, the technology and equipment of substrate cultivation of strawberries and aerosol cultivation of leafy vegetables have emerged. Technology is developing rapidly.
Intelligent control technology changes with each passing day.
The level of intelligent environmental control technology and equipment determines the operating efficiency of the plant factory. Intelligent environmental control is based on the principle of plant environmental control and particularly needs to be based on the physiological response effects of plants under the coupled control of environmental factors. It has been greatly developed. The physiological mechanism of plant environmental control is gradually being revealed, and the coupling control strategy has gradually matured, and a number of related companies and products have emerged.
The industry is developing very rapidly
Plant factories are the key research direction of modern agriculture, and there are many companies engaged in related technology and research equipment of plant factories. With the production of these companies, plant factories have developed rapidly. The plant factory industry in some developed countries has a certain scale and the industrial chain is quite mature, and some developing countries have the budding state of plant factories. Plant factories are very suitable for the development of countries where natural conditions are not conducive to agricultural production or countries with dense populations. In recent years, both smart factory technology and grow light LED technology have been developing rapidly.
The industry segmentation market is gradually completed
At present, the plant factory enterprise development model is divided into two types: technical equipment type and plant product sales type. The former replicate projects and promotes plant factory system equipment; the latter uses plant factories to produce plant products, especially high value-added plant products. From the perspective of the types of products sold, vegetable products and home gardening products are the mainstream.
The manufacturing of supporting equipment for plant factories is also developing rapidly
Suppliers of LED light sources, shelves, nutrient solutions, and control systems required by plant factories have increased year by year. For example, a light source supplier represented by MOKOLight can provide lamp beads with mainstream wavelengths in plant factories, providing a foundation for the creation of LED light sources.
Sunlight plant factories are increasingly rich in light supplement products
According to the plant light environment demand theory and basic threshold, combined with the lighting advantages of LED, the research and development of grow light LED are in full swing, the products are continuously launched, and the cost performance is increasing year by year. The water-cooled LED fill light represented by MOKOLight has market prospects.
High value-added healthcare plants have become the new favorites.
Ordinary vegetable products have low prices, large input-output ratios, and limited profit margins. Therefore, plant factory owners tend to produce high-value-added healthcare plants, and even deep-process fresh products to increase additional benefits.
LED plant factory light source and new developments in lighting research and development
Illumination is the main driving factor for the implementation of high-efficiency plant production in LED light source plant factories and plays an indispensable role in regulating plant growth and development and yield and quality formation. The adoption of suitable and cost-effective LED lighting products determines to a certain extent not only the production efficiency of the LED light source plant factory, but also the product value and its importance is self-evident.
LED light source products are becoming more abundant.
LED light sources used in plant factories have grown from scratch, from poor quality to sophisticated, from uncontrollable to intelligent control, and from high cost to low price. LED light sources are fully meeting the needs of plant factories. At present, there are multiple models and series of grow light LED, T5 and T8 specifications of LED tubes and light bars, water-cooled high-power LED light panels, high-power LED fill lights, and two-way illuminating LED light bars. How many of these products are The company can provide it with a large degree of freedom in product design, which can well meet market needs. However, there is still a lack of standards for LED light sources, which urgently need to be improved and formulated as soon as possible.
LED energy-saving and high-efficiency application technology is being solved.
From the perspective of setting and controlling the light quality, light intensity, and photoperiod of the LED light source, through reasonable coordinated coupling regulation of light quality, light intensity, and photoperiod, the cultivation efficiency can be improved on the basis of ensuring the growth and development of plants. At present, research on the control technology of light quality, light intensity, and photoperiod has become the focus of discussion. For example, Yu Yi et al. proposed the use of lettuce’s low light adaptability and the use of low LED light to improve production efficiency. Internationally, there are many studies on the improvement of vegetable quality by adjusting the LED light environment in plant factories. Bian et al. made a systematic review.
LED continuous light has become a hot spot.
Continuous lighting is an important lighting method to shorten the growth cycle of plants, increase yield, and improve quality. It has application prospects for specific plant species. Many countries in the world are doing similar projects: “The influence mechanism and rhythm effect of continuous LED red and blue light on the ASA metabolic network of high-nitrogen hydroponic lettuce” and the youth project “Nitrate metabolism and influence mechanism of hydroponic lettuce under short-term continuous grow light LED. Long-term research work has been carried out under the funding of “research”. This research will reveal the mechanism of continuous light, plant response, and its rhythmic effect strategy, and ultimately provide a basis for the application of continuous light in plant factories.
The R&D of LED lighting rhythm has become the focus.
Circadian rhythm is a physiological characteristic of plant growth and development, but how the rhythm of a plant changes under constant light in a plant factory has become the focus of research. Fully revealing the characteristics and evolution of plant rhythms under the conditions of red and blue LEDs in plant factories will provide a scientific basis for the efficient application of grow light LED sources.
The space-time control technology of LED light source is completed.
As a cold light source, LED can be used close to the plant canopy to effectively illuminate and improve the efficiency of light energy utilization. However, the plant height varies significantly from the seedling stage to the vegetative growth stage and even the reproductive growth stage. Therefore, in order to improve the light energy utilization efficiency of the whole growth period of the plant, it is necessary to adjust the vertical height of the LED light source so that the distance between the LED light source and the canopy is relatively constant, so as to achieve the purpose of energy-saving and high efficiency.
LED light formulas are becoming more abundant.
At present, the types of plants that can be cultivated by plant factories are very limited, and it is necessary to continuously expand the types of plants that can be produced by plant factories, and increase the types and varieties of leafy vegetables, root vegetables, stem vegetables, medicinal plants, and flowers. The basis for verifying that new plant species and varieties can be mass-produced in plant factories is the establishment of light formulas. Only when efficient light formulas are established can intelligent control of the light environment be achieved and high-commercial plant products can be produced.
The high-quality and high-yield vegetable in the plant factory has perfect lighting technology.
High-quality and high-yield is the goal of plant factory production, and light environment regulation is one of the main ways to achieve high-quality and high-yield plants. Through the regulation of light quality, light intensity, and photoperiod, it can change the nutrient absorption, primary and secondary metabolic processes of plants, regulate the synthesis, metabolism, and accumulation of sugars, vitamins, flavonoids, phenolic acids, and other substances in plants, and ultimately affect the edible plants Part of the health function. At present, in addition to photosynthetically active radiation, ultraviolet radiation has a unique role in regulating quality, and reasonable ultraviolet radiation dose will be the focus of research.
Summary
Now that the world’s population is increasing rapidly, the contradiction between population increase and the lack of arable land is becoming more and more acute. The food crisis occurs for a long time, and it is necessary to find more efficient and less land planting methods. Plant factories are a good solution. In addition, human beings Excessive dependence on the environment leads to serious environmental damage, soil erosion, and disruption of ecological balance in many places. Plant factories are the key to remedial measures. In addition, some areas are not suitable for crop growth and vegetables and fruits cannot grow in winter. Therefore, plant factories will develop vigorously and will become an important part of future agriculture. With the progress of related materials and production processes in recent years, the price of grow light LED has dropped a lot, related performance has been improved, and the market occupancy rate of LEDs has been greatly improved. grow light LED must be plant factories. Main light source.