The requirements of chili peppers for environmental conditions
Today, the editor will elaborate on the knowledge of melons, fruits, and vegetables, especially chili peppers, and their requirements for environmental conditions. The details are as follows:
Chili pepper growth and development and environmental conditions
Chili peppers are annual herbaceous plants that can complete the process from seed germination, seedling formation, flowering, and fruiting to seed maturity within a year. The growth and development of chili peppers is an important part of physiology, and the formation of seed production is realized through growth and development.
The growth process of chili peppers
During the growth and development of chili peppers, there is a close and mutually promoting but mutually restrictive relationship between vegetative growth and reproductive growth. Excessive growth of chili peppers will delay the flowering period and reduce the fruit-setting rate; while weak growth cannot provide the necessary nutrients for flowering and fruiting of chili peppers, which will seriously restrict the number of flowers and reduce seed production yield. Only by properly adjusting the relationship between chili pepper growth and development can high yield be achieved.
The period of chili pepper growth and development
The growth and development of chili peppers refer to the whole process from seed germination to regaining seeds. Chili pepper seed production includes the entire process of chili pepper growth and development.
1. Seed stage
The seed stage refers to the period from fertilization of the ovum to the germination of the seed, including the embryonic development stage and the germination stage.
(1) Embryonic development stage: from fertilization of the ovum to seed maturity. During this period, the seed's metabolism is in the same individual as the maternal plant, and after vigorous synthesis and accumulation of nutrients, the ovule gradually develops into a mature seed.
(2) Germination stage: After the seed matures and encounters suitable environmental conditions, it absorbs water and begins to germinate and grow. During germination, respiration is vigorous, growth is rapid, and the energy required for growth is entirely dependent on the stored substances in the seed itself. The amount of stored substances in the seed is determined by the accumulation of energy during seed development and the storage time and conditions after seed maturity, which greatly affects the speed of seed germination and the growth of seedlings.
2. Vegetative growth stage
(1) Seedling stage: from seed germination to before transplanting to the field. After seed germination, a new root grows first, absorbing water and minerals from the soil; after breaking through the soil, two cotyledons emerge and perform photosynthesis. Chili pepper cotyledons not only have a significant impact on the growth of seedlings but also on the growth status of chili pepper seedlings in later stages. The seedling stage has a large growth volume and very vigorous metabolism, and the nutrients produced by photosynthesis are almost entirely used for the growth needs of new roots, stems, and leaves.
(2) Growth stage: from after transplanting to before flowering. During this period, chili pepper roots, stems, and leaves enter a stage of vigorous growth, and the products of photosynthesis not only meet the needs of their own growth but also go through a process of nutrient accumulation, laying the material foundation for flowering and fruiting in the future.
3. Reproductive growth stage
(1) Flower bud differentiation stage: Flower bud differentiation is a morphological marker of the transition from vegetative growth to reproductive growth in chili peppers. After a certain period of growth, chili peppers will cause flower bud differentiation at the growth point, and then produce buds and flowers. This stage actually occurs before flowering.
(2) Flowering stage: Generally refers to the period from the opening of the first flower to the end of flowering. This stage is the key period for chili pepper seed production, and it has weak resistance to external environmental conditions, sensitive to temperature, humidity, and light. High or low temperatures, insufficient light, or excessive dryness can affect chili pepper pollination and fertilization, causing flower and fruit drop, and thus affecting seed production yield.
(3) Fruit-setting stage: From flowering and fertilization of chili peppers to the full maturation of the fruit and seed. This stage is an important period for seed yield formation. During the fruit-setting stage, the expansion and growth of the fruit and the embryonic development of the seed depend on the continuous transport of the products of photosynthesis from the leaves to the fruit and seeds.
When chili peppers enter the reproductive growth stage, vegetative growth does not stop, which means that this stage is a period of coexistence of reproductive growth and vegetative growth, and it is the most vigorous period in the growth and development process of chili peppers.
Three, the growth and development of chili peppers and environmental conditions
The growth and development of chili peppers depend not only on their own genetic characteristics, such as the resistance of chili pepper varieties to low temperature, high temperature, and drought, but also on external environmental conditions. Therefore, chili peppers are annual plants in the Yangtze River Basin and North China, dying each winter. In tropical or subtropical regions, such as Hainan Province, Guangdong Province, Guangxi Zhuang Autonomous Region, and southern Yunnan Province, chili peppers can overwinter outdoors. Chili peppers are native to the tropics, but under long-term natural and artificial selection, they have formed unique adaptability to external environmental conditions. They prefer warm temperatures, are drought-resistant, afraid of waterlogging, prefer light, and can tolerate weak light. In production practice, it is necessary to comprehensively consider the impact of various factors on the growth and development of chili peppers, seek benefits and avoid harms, and coordinate the development of various conditions to create a good environmental condition for the growth and development of chili peppers, thereby laying the foundation for high-yield seed production.
1. Temperature
Chili peppers are thermophilic crops, and the suitable temperature for seed germination is 25-30°C. The seeds do not germinate well or cannot germinate when the temperature is above 35°C or below 10°C. It takes 4-5 days to germinate at 25°C, 10-15 days at 15°C, more than 20 days at 12°C, and it is difficult to germinate or stops germinating below 10°C.
The suitable temperature for the growth and development of chili peppers is 20-30°C. When the temperature is below 15°C, growth and development are hindered, and continuous temperatures below 12°C may cause damage. Below 5°C, the plants may suffer from cold injury and die. After the seeds germinate and have three true leaves, they have the strongest resistance to low temperatures and can tolerate short periods at 0°C without cold injury, which is the reason why young seedlings in cold beds can survive the winter.
The suitable day-night temperature difference for the growth and development stage of chili peppers is 6-10°C, with a daytime temperature of 26-27°C and a night temperature of 16-20°C being more appropriate. Different stages of growth and development have different temperature requirements. During the seedling stage, a daytime temperature of 30°C can accelerate seedling emergence and growth, while maintaining a lower night temperature of 15-20°C to prevent seedling stretching. Temperatures below 15°C inhibit flower bud differentiation; at 20°C, flower bud differentiation begins and takes about 10-15 days. Pollination and fruit setting are more suitable at temperatures of 20-25°C. Below 10°C, pollination is difficult, causing flower and fruit drop; above 35°C, due to incomplete flower development or dry stigma, flowers drop without fertilization, and even if fertilized, the fruit does not develop and withers. Fruit development and color change require temperatures above 25°C.
2. Light
Chili peppers are light-loving crops. Except for the seed germination stage, they require sufficient light in other growth stages. Good light during the seedling stage is a necessary condition for raising strong seedlings. Sufficient light results in short internodes, sturdy stems, thick leaves, dark green color, developed roots, and strong resistance to adversity, making them less susceptible to diseases. In winter and spring, there is often more rain and snow during chili pepper seedling raising in China, and the light intensity does not reach the light compensation point of 15,000 lux for chili peppers. Therefore, it is necessary to ventilate and expose to light frequently to increase light. Sufficient light during the adult plant stage is an important condition for promoting the branching, sturdy stems, large leaf area, thick leaves, abundant flowering and fruiting, and high yield of chili peppers. Insufficient light often causes plant stretching, thin stems, and leaves, poor development of flower buds and fruits, and prone to flower, fruit, and leaf drop. Therefore, when arranging hybrid chili pepper seed production, there should be no tall-stalked crops around to prevent shading and reduce yield; also, attention should be paid to cultivation management and avoid dense planting to prevent crowding of branches and leaves; and weeds should be cultivated and removed frequently to prevent them from competing with chili peppers for space. Excessive light is also not good for chili pepper growth. Under the strong sunlight of summer, when the light intensity exceeds 30,000 lux, it can cause leaf drought, hinder growth and development, close stomata, reduce photosynthesis, and even cause leaf scald. Theoretically, chili peppers are short-day plants, but as long as the temperature is suitable and the nutritional conditions are good, the length of daylight will not affect flower bud differentiation and flowering. When the plants have 1-4 true leaves, they can respond to the photoperiod.
3. Water
Chili peppers are the most drought-resistant crop among solanaceous vegetables. The required amount of water during the growth and development process is relatively small, and the water requirements are different at each growth and development stage. Generally, small fruit varieties are more drought-resistant than large fruit varieties. Only after the seeds absorb sufficient water can they germinate normally, generally requiring soaking for 6-8 hours before germination. Too long or too short a soaking time is not conducive to seed germination. Seedlings require less water, and excessive soil moisture at this time can lead to poor aeration, poor root development, weak plant growth, poor resistance to adversity, and susceptibility to diseases. After transplanting, the growth of chili peppers increases, and the water requirement increases, requiring appropriate watering to meet the growth needs of the plant, but water should still be controlled to benefit underground root growth and prevent plant stretching. During the early flowering stage, the water requirement increases, and the water supply should be increased to meet the needs of flowering and branching. During the fruit expansion stage, more water is required. If the water supply is insufficient, the fruit expansion rate will be slow, the fruit surface will wrinkle and bend, the color will be dull, and畸形 fruits will form, reducing the thousand-seed weight and affecting yield and seed quality. However, excessive water can easily lead to flower, fruit drop, rotting fruit, and dead seedlings. Air humidity also affects the growth and development of chili peppers. Generally, when the air humidity is between 60-80%, the plants grow well, and the fruit-setting rate is high. Excessive humidity hinders pollination. Excessive soil moisture, high air humidity, easily causes root rot, yellowing and dropping of leaves, flower buds, and fruits; if flooded for several hours, it can lead to mass death.
4. Nutrients
Chili peppers have high requirements for nitrogen, phosphorus, potassium fertilizers, and also need to absorb various trace elements such as calcium, magnesium, iron, boron, molybdenum, and manganese. Throughout the growth stage, chili peppers require the most nitrogen, accounting for 60%; potassium is second, accounting for 25%; and phosphorus accounts for 15%. Sufficient nitrogen fertilizer is necessary for the growth and fruiting of chili peppers. Insufficient nitrogen results in矮 plants, small leaves, few branches, and small fruits. However, excessive nitrogen fertilizer, lacking in phosphorus and potassium fertilizers, can cause plant stretching and susceptibility to diseases. Phosphorus fertilizer can promote the development of chili pepper roots, and potassium fertilizer can promote the strengthening of stems and fruit expansion. The requirement for various nutrients differs at different growth stages. Seedlings require less fertilizer but need comprehensive nutrients, otherwise, it will hinder flower bud differentiation, delay flowering, and reduce the number of flowers; excessive nitrogenous fertilizer during the early flowering stage can cause stretching and lead to flower and fruit drop, tender branches and leaves, and induce diseases; after fruit setting, sufficient nitrogen, phosphorus, and potassium nutrients need to be supplied to increase the thousand-seed weight.
5. Soil
Chili peppers are not strict about soil requirements and can be planted in various types of soil. Chili peppers are sensitive to soil acidity and alkalinity and grow well in neutral or slightly acidic soil (pH between 6.2-7.2). After pollination and fruit setting, chili peppers require higher fertilizer and water, and it is best to choose loamy soil with high water and fertilizer retention and fertility level. Generally, sandy soil is easy to grow seedlings, and seedlings grow faster in the early stage and have good fruit-setting, but it ages easily, and the fruit is small, and if fertilizer and water are not supplied, the seed production yield is low. Clay soil has slower seedling growth but more stable growth, and has strong water and fertilizer retention in the later stage, which is beneficial for high-yield seed production; the disadvantage is that it is not suitable for fine cultivation in the early stage and is more labor-intensive.
The above content on the requirements of chili peppers for environmental conditions is provided for your reference, hoping it will be helpful to green plant enthusiasts!