What are the effects of temperature on flower growth and development?

What should we do about the impact of temperature changes on plants and flowers.

The growth and development of plants are closely related to temperature, and temperature mainly refers to air temperature, soil temperature and leaf surface temperature. The temperature conditions required for flower growth and development are related to their origin and variety characteristics. The effects of temperature on the growth and development of flowers are mainly as follows.

1) Temperature affects the dormancy and germination of flowers. This affects the dormancy and germination of flower buds of seeds, bulbs and roots.

2) Temperature influences the growth process of flowers (vegetative growth). The vegetative growth process of flowers includes stem elongation, lateral bud germination, internode elongation, and the number of hair leaves, etc., all of which require suitable temperature. The effect of temperature on growth mainly occurs through the influence of physiological metabolism, such as temperature affecting photosynthesis, respiration, transpiration, material absorption and transport, etc.

3) Temperature affects the flower development process. Including flower bud differentiation, flower bud elongation, flowering, fruiting, and fruit ripening.

In the process of growth and development of flowers, the temperature directly affects the physiological activities of flowers, such as enzyme activity, photosynthesis, respiration, and transpiration, which have formed inherent special properties in the place of origin. Due to the change of temperature cycle, it can directly affect the growth of flowers, flowering, and the number and size of flowers.

The normal life activities of organisms are generally carried out in a relatively narrow temperature range, roughly between minus a few degrees to about 50 degrees. The effect of temperature on organisms can be divided into the lowest temperature, the optimal temperature and the maximum temperature, that is, the three-cardinal point temperature of the organism. When the ambient temperature is between the lowest and the most optimal, the physiological and biochemical reactions in the organism will accelerate with the increase of temperature, and the metabolic activity will be strengthened, thereby accelerating the growth and development rate. When the temperature is higher than the optimal temperature, the enzyme system involved in physiological and biochemical reactions is affected, and the metabolic activities are blocked, which will inevitably affect the normal growth and development of organisms.

When the ambient temperature is lower than the minimum temperature or higher than the maximum temperature, the organism will be seriously harmed and even die. The temperature of the three cardinal points is not the same for different organisms, and even the range of temperatures that the same organism can tolerate at different stages of development varies greatly. In addition, there is an effective accumulated temperature rule for the effect of temperature on biological development, especially in plants.

When other environmental conditions are constant, the change in light intensity determines the change in net photosynthesis. When the light intensity is lower than the light compensation point

point), the plant is in a state of consumption without accumulation, and only when the light intensity exceeds the light compensation point, the plant has organic matter accumulation. Under the action of strong light exceeding its light saturation point, the overload of the photosynthetic process will lead to the reduction of the utilization rate of light quanta, the decrease of photosynthetic production, and the excessive light will even cause the destruction of photosynthetic pigments and thylakoid structures.

Light intensity plays an important role in plant growth and development and the establishment of morphological structure. Light is the energy of organic matter synthesis in green plants**, and the amount of organic matter accumulated will inevitably have an impact on plant growth; The formation of many organs in plants and the proportions of each organ and tissue are directly related to the intensity of light. Etiolation is an example of how severe or no light can affect plant growth and morphogenesis.

The internodes of yellowing plants are particularly long, the leaves are underdeveloped and small, the lack of chlorophyll and the appearance of yellow, the water content of the plant body is high, the parenchyma is developed, the mechanical organization and vascular bundle differentiation are very poor, especially the tissue of water transport and conduction is not developed. Insufficient light can cause nutrient disorders in plants**, leading to flower buds that have already formed, stunted fruit development or early death, and also affecting the quality of the fruit. One of the purposes of necessary pruning of fruit trees is to make the branches and leaves of fruit trees reasonably distributed, and the fruit trees can receive light better inside and outside, so as not to affect flowering and fruiting.

Temperature affects the growth and development of flowers, the highest, lowest and most suitable temperature for flower growth and development, we call it the temperature three basis points of flower market growth and development. Under the optimal temperature, the growth and development of flowers is the best, when gradually deviating from the optimal temperature, the growth and development of flowers is hindered, when the flowers can not bloom, when the maximum and minimum temperatures are exceeded, many flowers stop growing, when the limit temperature of survival is exceeded, the flowers will die, this limit temperature can also be called cold dead center and hot dead center. Knowing the requirements of the three basis points of temperature of flowers, let's discuss the influence of temperature on the growth and development of flowers.

Flowers have different temperature requirements at different stages of development. It requires a low temperature during the seedling period, and gradually increases as the seedling grows until it reaches the stage of flowering and fruiting. We all know that annual flowers are sown in spring, bloom in summer and autumn, bear fruit, and then die, so the natural temperature can just meet the requirements of his growth and development.

The seeds of biennial flowers need to be at a lower temperature, and during the seedling period, the temperature is required to be lower, otherwise, it will not be able to pass the vernalization stage smoothly. And when it comes to flowering and knotting, the temperature needs to be high. We have learned that the two-year-old flowers are autumn sowing flowers, the autumn temperature is relatively low, the seedling period is just in the lower temperature of the winter, flowering and fruiting is in the spring and summer temperature gradually rises, the natural temperature can just meet her flower bud differentiation.

Different flowers need certain temperature conditions, flowers of different origins, its flower bud differentiation has different temperature requirements, the first type is to carry out flower bud differentiation at high temperature. Annual flowers, the species that bloom in summer and autumn among the root flowers, and most of the bulb flower species need flower bud differentiation at higher temperatures. For example, bulbous flowers such as gladiolus and canna should be divided into vernal during the summer growth period, and bulbous flowers such as tulips and hyacinths should be planted in autumn to differentiate flower buds during the summer dormant period.

The second type is flower bud differentiation at low temperatures. Some alpine flowers native to the north-central temperate zone require flower bud differentiation below 20 degrees, and some biennial flowers and spring-flowering root flowers also need to be differentiated when the spring temperature is low.

Protection: The front is normal natural temperature, in practice, sudden high and low temperature, this irregular temperature change has a greater impact on the growth and development of flowers, especially sudden low temperature will often occur, in order to reduce the damage of sudden low temperature to flowers, we need to take measures to improve the cold tolerance of flowers in addition to cold measures. For example, when cultivating potted flowers and seedlings in greenhouses or greenhouses, before transplanting land, it is necessary to strengthen ventilation and gradually reduce the temperature ratio to increase its cold tolerance.

Before the onset of winter, you can apply more phosphorus and potassium fertilizers and less nitrogen fertilizers, so that the cold resistance of flowers can also be enhanced.

The content comes from the MOOC Nanjing Forestry University - Professor Lin Runan's "Floriculture".

Generally speaking, the higher the temperature, the stronger the photosynthesis of plants, the more organic cave matter produced, and the stronger the respiration. At 10 ! In the 32 range, for every 10 increase in temperature, the rate of respiration of flowers increases by about 2 times, which is beneficial for the robust growth of flowers.

However, it is the same flower, and its temperature requirements are different at different stages of development.

For a period of time after sowing, you need to keep the temperature relatively high, which is helpful for your seeds to absorb water, and it is also more beneficial for the germination and excavation of seeds. However, after the seedlings are unearthed, it is best not to have too high temperatures, so as not to grow the plants.

After the plant enters the vegetative growth phase, it needs to have a higher temperature to promote the growth and development of flowers. Finally, during the flowering stage, the flower needs to be hot again, and on the contrary, a lower temperature at this time will be conducive to its reproduction and growth. Many flowers stop blooming in the summer because the temperature is high, which curbs the flowering and renting.

For biennial flowers, the seed germination stage requires a lower temperature; Seedlings need a lower temperature during growth, preferably 1 15. Because after low temperature exercise, it is conducive to flower bud differentiation through vernalization, but after entering the vegetative stage, a higher temperature is needed to promote its growth and development.