Main biological characteristics and main cultivation and management techniques of ornamental pineapple

Main biological characteristics and main cultivation and management techniques of ornamental pineapple

The ornamental type of pineapple, also known as pineapple flower, is the most varied perennial herb in the pineapple family. In Monocotyledons, the pineapple family alone contains more than 50 genera, more than 2500 species, and more than 1000 hybrids alone, both genera and species are a large number of subjects. Due to the high appreciation value of ornamental pineapple varieties, compact plant type, good leaf gloss, different flower patterns, rich flower color and long flowering time, most ornamental pineapple flowering time is about 90 days. Whether it is inflorescence, cotyledon or fruit has a unique appreciation value, so it can be comparable with tropical orchids, andrographis andraeanum and other tropical plants, but also the current sales of indoor high-grade ornamental plants. The country of origin is in the tropical rain forests and coastal areas of Central and South America, grows in a warm and humid semi-shaded environment, and has long been attached to the trunk or stone wall of forest plants. at present, the ornamental pineapple cultivated by artificial hybridization has replaced the original variety, and the most common ornamental pineapple in the flower market is mainly fruit vine, more than 200, all of which are selected through cross breeding for many generations. Excellent quality, bright colors, occupy a large proportion in the market sales.

1 main biological characteristics of ornamental pineapple

1.1 morphological characteristics

1.1.1 roots. The roots of ornamental pineapple are mostly fibrous roots, most are black, some are brown, only a small part of the roots are green, and are directly exposed to nature for a long time. The root system of ornamental pineapple is very fine and has many branches, and the top root of the new root has dense hair, which is mainly used as a fixed stem and corresponding absorption. The newly emerged root system has a very strong function of regeneration and can grow directly in a wet flowerpot without root cultivation. There are some aerial type pineapple varieties, even mature plants have no root system. Its growth and development mainly depends on obtaining the necessary nutrition and water from the air.

1.1.2 Stem. The main function of the stem of ornamental pineapple is to support leaves and inflorescences, and to transport water and nutrients needed for growth and development. Nutrients can be stored in the stem, and more growth hormone at the top of the stem can promote the rapid growth and development of plants. The stem part can be divided into aboveground and underground parts, most of the aboveground parts are very short and small, surrounded by leaves and can not be found, only some PUYA pineapple, Tillandsia recurvate varieties aboveground stem part is very obvious, such as some Aechmea coral type pineapple aboveground part of the stem is creeping, the plant at the top of the stem will replace the flowering dead plant for growth and development, the underground stem part is mostly fibrous root It has more branches, showing the characteristics of Lignification, which is directly covered by soil, and only some underground stems of aerial pineapple are exposed and grow in nature.

1.1.3 leaves. Most of the ornamental type pineapple cotyledons show wide frequency, some are linear, needle-like, most of the cotyledon surface is leathery or fleshy, the leaf edge is serrated, some of the cotyledons are rough, and the nutrients needed for growth and development can be obtained from the air. The cotyledons of most pineapple varieties are rich in structure, and different cotyledons cross each other to form a lotus-shaped water storage cup at the base of the plant, which can also be called a leaf cup. All the nutrients and water needed in the growth and development of ornamental pineapple are provided by the leaf cup, which is more prominent than the root system. According to the relevant research, there are 175000 pineapples in the forest of 10000m2, and the actual water storage capacity is more than 50,000 L, so in the process of artificial cultivation of ornamental pineapple, only irrigation and fertilization is needed in the leaf cup.

1.1.4 flowers. The flower of an ornamental pineapple generally refers to all inflorescences, not just a simple flower. Ornamental pineapple has many flower patterns, which can be said to be in a variety of ways, with very bright colors, long flowering period and beautiful appearance, so it is very popular among the broad masses in the market. The flowers of ornamental pineapple are mostly spikes, compound spikes and cones. Most of them are covered with bright bracts, there are some pedicels developed directly from the leaf cup, and a few are heads hidden in the leaf cup for flowering. In fact, the real ornamental pineapple flowers are not large and are generally hidden in the leaves of the brightly colored bud. Most of them are bisexual flowers, and some are unisexual flowers. There are 3 sepals, 3 petals, some pineapple varieties are separated, some are directly tubular at the base; 6 stamens are arranged in 2 rows, anthers show free development, 2 chambers; pistils total 3 connate, style thin and long, with 3 main heads, separate growth, ovary inferior or semi-inferior, 3-loculed, there are multiple ovules in each chamber.

1.1.5 fruits. Most of the fruits of ornamental pineapple are berries and capsules, and some are flowers, usually with oval, round and long-shaped sepals, which can have a variety of colors at maturity, such as red, blue, white, etc., the main function is to attract birds to find food, and then spread.

1.2 Ecological habits

The ecological habits of ornamental pineapple varieties are closely related to the growth environment. Different types of pineapple are adaptable to light, sensitive to temperature and humidity, need nutrients, and have different responses to culture media. In the ornamental type of pineapple varieties, epiphytic varieties account for about 80%. There are lotus-shaped leaves at the base of these pineapples, that is, leaf cups, whose main function is to maintain the nutrients and water needed for the normal growth of plants. Epiphytic pineapple varieties are the most classic tropical crops, which need higher temperature to develop within one year, and have a certain demand for light time and appropriate humidity, which are the key factors to promote their healthy development.

Most of the seed leaves of ornamental pineapple are leathery, some are fleshy, they are serrated at the edge, prefer long light time, and grow up in a warm and humid environment. Some ornamental pineapple seeds are fleshy and can live in desert areas with poor environmental conditions. The edge or tip of the leaf is serrated or tip. There are also some terrestrial ornamental pineapples growing in the plateau, which can adapt to high-intensity ultraviolet direct irradiation and large temperature difference between day and night. Such varieties have tall plant type, blossom once after growth and maturity, and then reproduce. The aerial ornamental pineapple is mainly produced in Latin America, and it mainly grows in the areas where Rain Water is relatively insufficient, the cloudy weather is more, and the sun is exposed to more than 1500m above sea level for a long time. The plant type is small, the root system is not many, and there are many silver scales on the cotyledons. Can directly absorb the necessary water and nutrients from the air. And aerial varieties and other pineapple ecological habits are different, can achieve symbiosis with ants, is a typical ant habitat plant. The ornamental type of pineapple is a plant of acid metabolism in crassulacea. the stomata are usually closed during the day, and only at night they open to breathe, absorb carbon dioxide and release oxygen. the nutrients accumulated by photosynthesis in the daytime are transformed into nutrients urgently needed for plant development, which is contrary to the photosynthesis carried out by ordinary plants.

2 main cultivation and management techniques of ornamental pineapple

2.1 planting plan

The size of the ornamental pineapple plant type directly determines the size of the flowerpot to be cultivated. Generally speaking, the flowerpot with a diameter of 10cm is the most suitable for planting 10~12cm-high ornamental pineapple seedlings. Different flowerpots are closely placed, and 1m2 can be placed in 100pots. According to seasonal differences, the actual growth and development rate of pineapple is also different. Generally, it is about 4 months after cultivation to be planted in a flowerpot with a diameter of 14cm, with an average 1m2 of about 25 pots. After 5 months of cultivation, artificial sparse seedlings were carried out to widen the original spacing, and the average 1m2 was placed in about 15 pots. Some special ornamental pineapple varieties finally needed 18cm flowerpots, which were changed after 4 months of cultivation and increased the placement distance at the same time.

2.2 Matrix

The root system function of ornamental pineapple varieties is to support root growth and development and absorb nutrients needed for growth. The requirements of humus contained in the substrate in the process of cultivation are not very strict, but they must also be light, loose and have a good water retention capacity. In most cases, the mixture of peat soil, perlite and coconut bran mud is selected as the substrate, and it is suitable to stir according to the above three kinds of substrate volume ratio of 10 ∶ 1 ∶ 1. 1% formalin solution can be sprayed to disinfect the substrate. After stirring, it is covered and sealed with plastic film, so as to use formalin to achieve the purpose of fumigating and eliminating the seeds of diseases, insect pests and other weeds contained in the substrate. After 30 days, the covered plastic film was opened, and the matrix was spread out to volatilize the remaining formalin, which could be used normally after 1 week.

2.3 temperature and humidity management

The temperature and humidity of ornamental pineapple can grow normally under the condition of 5-37 ℃. The most suitable temperature is 10-18 ℃ at night and 21-32 ℃ in daytime. The temperature difference between daytime and night is more than 6 ℃. The most suitable air relative humidity is 62%, > 80%, under the condition of high temperature and humidity, timely ventilation is needed, and when < 40%, under the condition of high temperature and low humidity, it is necessary to water as soon as possible. you can't continue spraying water under the condition of low temperature in winter, but when you feel stuffy, you should turn on the fan in time to continue air convection.

2.4 Lighting Management

The growth and development status, flower size and color of ornamental pineapple are directly related to the light intensity. In the appropriate light range, increasing light intensity can accelerate the growth and development of ornamental pineapple, the leaves are compact and thick, the plant grows and thrives, the length of inflorescence growth and development is large, the Corolla is large, and the flower color is diverse. In most cases, the range of light needed for pot planting at seedling stage is 8000Lx. One week later, the light amplitude was set at 12500LxMagol for 90 days and then set in 22500Lx, and the most suitable light amplitude was 18000Lx.

2.5 Water and fertilizer management

Ornamental type pineapple varieties have leaf cups at the base, which can ensure the normal growth and development of plants. The water temperature requires 18 ℃, and the most suitable humidity at seedling stage is 82.5%. After 3 months of cultivation, the humidity should be controlled at 7580%. If the humidity is too high, it is easy to grow fungi, and if the humidity is too low, it will slow down photosynthesis. Rain Water irrigation is the best, followed by pure water after treatment. because ornamental pineapples mainly rely on leaf cups to absorb water and nutrients, liquid fertilizer should be used. Ornamental pineapple is very sensitive to some elements, applying too much copper and chlorine will cause the plant to blacken and eventually lead to death; too much zinc will make its leaf tip dry; boron will cause leaf curl or shedding; too much phosphorus will also cause symptoms of poisoning, such as leaf tip dryness. More magnesium is needed in the leathery state of cotyledons, if magnesium can be satisfied, then the leaves will directly emit the metallic luster of magnesium. Therefore, adaptive magnesium should be added to the fertilizer, which is generally added according to 10% of potassium.

2.6 flowering management

It takes a long time for ornamental pineapples to blossom under natural conditions. In the actual cultivation process, in order to achieve better consistency and uniformity, to achieve the expected sales time and price, artificial flower induction is necessary, which is very important in the production process. The main method is to change the acetylene gas in water for 0.5 h into acetylene saturated water solution, then close the acetylene cylinder and pour the acetylene water solution directly into the plant leaf cup, once every 3 days, each time about 150mL, a total of 3 times. The specific date of flowering should be carried out within 2 months before the target flowering time, no fertilization should be applied within 1 month before flowering, and the watering times should be properly controlled to keep the plant relatively dry, and fertilizer should be applied within 1 month after the end of flowering, and potash fertilizer should be applied mainly.

2.7 Pest management

When ornamental pineapple grows in greenhouse, Spodoptera litura occasionally appears in the seedling stage, and there are no insect pests in most cases. If too much watering, the water quality is not good, the most likely to appear is heart rot, the main symptom is gradually blackened from the base of the leaves, the heart leaves appear brown rot, easy to fall off, and the disease-free leaves are significantly different. At this time, the diseased plants should be removed as soon as possible, and the carbendazim solution should be added with watering and fertilization, the concentration is 0.1%, watering once a week. It is necessary to have more ventilation, disinfect the heart leaves regularly in the greenhouse and often wash the heart leaves with clean water.