The orchid is boundless-the growth characteristics of orchids

The plants of Orchidaceae are mainly composed of leaves (leaf), pseudocorms (pseudobulb), sheath leaves (sheath leaf) and hypertrophic roots (root). Both leaves and sheath leaves have latent buds at the junction with the pseudocorms. The germination of these latent buds is controlled by terminal bud dominance (Apical dominance). The latent buds above the inflated parts of the pseudocorms are less likely to germinate, while the latent buds below the inflated parts of the pseudocorms are easier to germinate. Latent buds can germinate into vegetative buds or reproductive buds, which are greatly affected by light intensity and bud position. when the light intensity is insufficient, the production of photosynthetic products decreases, resulting in low carbon / nitrogen ratio in the plant, and prone to the situation that pseudocorms are thin and small, and flower buds cannot be formed. latent buds located at lower nodes (lower node) are more likely to germinate into vegetative buds, and latent buds at higher nodes (upper node) on pseudocorms are easier to germinate. Often develop into flower buds to form inflorescences, and if latent buds differentiate into vegetative buds (leaf buds), then expand the leaves and begin to accumulate nutrients after the leaves are fully extended, so that the pseudocorms at the base of the buds begin to expand rapidly, forming the second generation of pseudocorms, so it is common to see several plants linked together. After pseudobulm hypertrophy, if the nutrient supply continues to be sufficient, the latent buds can differentiate into flower buds under appropriate low temperature stimulation, and can blossom in winter and spring. The whole growth cycle starts from latent buds germinating into leaves, flower buds differentiate and blossoms, and the vegetative buds germinate again in the following year, which lasts about one year. In addition to the above-mentioned factors such as bud position and terminal bud dominance, how to promote the rapid expansion of pseudocorm to achieve the purpose of rapid propagation is the focus of Lanyou. The following factors such as luminosity, temperature, nutritional requirements and cultivation media are introduced as follows: (1) Photoperiod is a negative plant with low photometric demand, and it is often cultivated with shade net and simple installation. However, although the leaves are longer under excessive shade, the amount of dry matter will be reduced, which will make the pseudobulm thin and dysplastic, and even cause the situation that it can not blossom. The ideal degree of shade is about 50% 75% of that of full sunlight, and the average luminosity is about 10000~20000lux. (2) temperature and temperature have important effects on the germination rate, leaf differentiation and growth, flower bud differentiation and flowering of latent buds on Pseudomonas aeruginosa. Low day / night temperature (20 ℃ 15 ℃) was the most favorable for leaf differentiation and pseudocorm development, but poor for latent bud germination. In order to promote the rapid germination of latent buds, the leaf elongated rapidly, and the high day / night temperature (25 °30 pm 20 ℃) was the best. For its stem and flower bud development in the later stage, 25 ℃ was the best. If the flower bud was too low, it was easy to produce deformed flowers. After flower bud differentiation, if the continuous high temperature (> 30 ℃), the flower bud could not elongate, but the flower bud could not elongate rapidly when the temperature was 20 ℃ and 15 ℃. (3) Nutrition demand for Cymbidium plants, nitrogen fertilizer has the greatest effect on their growth. Although the demand for phosphate fertilizer is not as high as nitrogen fertilizer, it plays an important role in the enrichment and flowering of pseudobulm, so it should not be neglected in fertilization. and attention should be paid to the supplement of trace elements. In addition, the amount of fertilizer application had sympathetic effect with light intensity. Under the cultivation environment of 10000~20000lux, the effect of fertilization was not significant, but under lower light intensity (below 10000lux), fertilization could make up for the effect of low light stress on vegetative growth. At present, there are a variety of fertilizer commodities on the market to choose from. in terms of the effect of fertilization, chemical quick-acting liquid fertilizer can be quickly absorbed by the plant after application, and it is the fastest topdressing fertilizer, while the effective granular chemical fertilizer has a fertilizer effect as long as 1-2 months. it is convenient to use and saves labor, but the import unit price is higher and the cultivation cost will be slightly higher. In recent years, there are many kinds of organic granule fertilizer available for selection. There are two points to pay attention to when using: 1. Fertilizer should be fully fermented to avoid harming orchid plants due to fermentation. two。 Some organic fertilizers will be combined with microbial fertilizers, and bacteria will be produced after application. It is appropriate to observe the reaction after co-growth with orchid plants, and then decide whether to apply them in a large area.