The plant rental company explains the orchid: the influence of light on flowering

National orchid is a precious ornamental plant, according to incomplete statistics, there are more than 700 genera, more than 20,000 species, and many new varieties are found and cultivated every year。In plant taxonomy, the orchid belongs to the monocotyledonous perennial orchid family。 Orchid is also the most commonly used plants in green plant rental companies, which can generally be placed on the company's top desk。

The national orchid is a kind of orchid herb that grows in the deep mountains and forests。The national orchid usually refers to the spring orchid (Cymbidiumgoeringii), the Jianlan (C.en-sifolium, Cymbidium flabed, Cymbidium flabed (C.kanran), Moran (C.sinense), Spring Sword (C.tongibracteatum) and the lilac orchid (C.tortisepalum) 7 kinds of orchids。The fragrance of the orchid is fresh and elegant, pure beauty and quiet, thick and light, refreshing the heart and the heart, making people hear for a long time。Orchid color is simple and elegant, plain and unadorned, by more and more people love。 

　　Under normal growth conditions, the flowering period is from January to March, the flowering period of spring orchid is from February to March, the flowering period of cymbidium is from March to May, the flowering period of Cymbidium is from July to October, and the flowering period of cold orchid is from November to December。The flowering period of the orchid is mainly from December to March of the following year。It can be seen that the flowering time of the orchid is relatively scattered and most of them are staggered with holidays。Therefore, it is not possible to provide the public with a large number of high-quality orchid varieties during the festival。The flowering regulation of the orchid refers to the artificial adjustment of its growth environment conditions or the use of some special technical measures and management methods on the basis of fully understanding the growth and development law of the orchid, so as to achieve the purpose of making the orchid bloom early, late or extend the flowering period。 

　　1. The influence of light on the flowering period of Chinese orchid 

　　Light is one of the main factors that affect the flowering time of Chinese orchid。The influence of light on the flowering period of Chinese orchid mainly includes light intensity, light quality and photoperiod。Various kinds of light receptors in plants play a major role in the process of sensing changes in the external light environment。In 1934, KNOTT's local shading experiments confirmed that light receptors were widely distributed in the leaves of plants。The light receptors in the leaves are like the "eyes" of the plant, sensing whether the environment in which the plant is growing is day or night, shade or sunlight。The response system in the plant body responds in time according to the change of light environment, so that the plant is in a relatively perfect growth state, and has a regulating effect on the induction of flower formation of the plant。 

　　1.1 Effect of light intensity on flowering time of Chinese orchid 

　　Light intensity is the intensity of light。According to the different needs for light intensity, plants can be divided into three categories: ① positive plants: normal growth and development of plants require full light irradiation。② Negative plants: normal growth and development of plants require moderate shade or scattered light irradiation。③ Neutral plants: the demand for light intensity of plants is between the above two。The orchid is a female plant, its light saturation point is 200 ~ 600umol/ (m2·s), the light compensation point is 5 ~ 50 umol/ (m2·s), so they can not tolerate strong direct light, can only grow well under moderate shade conditions。 

　　Under normal circumstances, flowers need strong light before flowering, but after flowering, they need low light intensity to extend the viewing period of flowers。If the light is too strong during the flowering period, the flowering period will be shortened。Huang Yongyi et al. believed that in a certain range, strengthening the light intensity was conducive to the flower bud differentiation of the lotus orchid, so as to advance its flowering period。If the light intensity is too strong or too weak, it is easy to reduce the number of lotus petals and orchid buds, so that the flowering period is advanced or delayed。 

　　1.2 Effects of light quality on flowering time of Chinese orchid 

　　Photomorphogenesis of plants is mainly restricted by the characteristics of light quality, and it is mainly involved in regulating the differentiation of plant organs, flowering and allotment of plant assimilates。Photochromes (which mediate red and far-red light), cryptochromes (which mediate blue light and UV-B reactions), and photoreceptors that mediate NV-B reactions are the three types of photoreceptors currently known。Among them, photoallergens are the most clearly studied photoreceptors so far。Photochromes exist in plants in two forms: Pr (red light absorption type) and Pfr (far red light absorption type)。 

　　Liu Ming et al. found that far red light and blue light can promote plant flowering, while red light will inhibit flowering。This may be because far red light and blue light treatment can significantly promote the accumulation of dry matter to flower organs and promote flower bud differentiation。Liao Xiangru et al. (iv) found that wild-type plants flowering late under red light conditions, and flowering early under blue light。The study of Huangxuemei ml confirmed that neither red light nor blue light treatment could significantly increase the number of spring orchids or advance their flowering time。 

The influence of flower photo on the flowering time of national orchid

　　1.3 Effect of photoperiod on flowering time of Chinese orchid 

　　The alternations of light and darkness during the day and the length of their duration have an important effect on the flowering of plants。We call this photoperiodic phenomenon。 

　　Photoperiodic pathway is a relatively conservative floral signaling pathway。Most plants have their own biorhythms, which affect the flowering of plants by sensing changes in the external light environment (i.e. the length of light)。First, the mature leaves of the plant sense the photoperiodic signal, and the resulting flowering signal substance is transmitted from the leaf to the stem tip, causing the stem tip to bloom。Therefore, plants can bloom earlier or later by changing the length of the photoperiod。Most test results show that there is no difference between long and short sunshine。For example, Huang Yongyi et al believe that the length of light time has no significant effect on the flowering period of lotus petals。Old experiments by Lu Guozhi and others found that supplementing light also failed to significantly advance the flowering date of Molan orchid。However, the experimental results of Huang Xuemei et al., showed that long sunshine can promote the reproductive growth of spring orchid, so that its flowering time is advanced。Gong Tian's experiment proved that shortening the time of illumination could advance the early flowering of Han LAN。This may be due to the accelerated flower bud differentiation caused by the photoperiod induction similar to autumn。The flower bud differentiation of cold orchid is accelerated and more small flowers are produced, thus prolongs the inflorescence flowering period of cold orchid。Therefore, whether the orchid is diurnal neutral flower and whether the duration of light will affect its flowering period during development are the problems that we need to focus on in the next step。