Flower name: Tulip

　　Scientific name: Tulipa gesneriana Latin name: Tulipa Other names: foreign lotus, dry lotus, grass musk, fragrant

　　Family: Liliaceae, Tulip Genus. The national flower of the Netherlands. As the main export ornamental crop of the Netherlands, it has become one of the lifelines of the Dutch economy and is known as the symbol of the Netherlands together with the windmill.

　　2. Origin of the name Tulips are native to the Middle East and were introduced to Europe in the 16th century. In the Middle East, people always associate them with Muslim headscarves. Because its flowers resemble Muslim headscarves, Persian called it dulband, and Turkish borrowed it as tulbend, meaning "Muslim headscarf." The word entered English through French tulipe/tulipan and Latin tulipa, evolving into the form of tulip. The Turkish word tulbend entered English through another channel and became turban, still referring to "Muslim headscarf."

　　 Morphological characteristics: Perennial herb. The bulb is ovate, about 2cm in diameter, with a papery outer layer and a few hairs on the top and base of the inner surface.

　　Leaves are 3 to 5, oblong-lanceolate or ovate-lanceolate, 10 to 21 cm long and 1 to 6.5 cm wide; 2 to 3 basal ones, relatively wide, 1 to 2 stem ones. The flower stem is 6 to 10 cm high, solitary flowers grow at the top of the stem, large and upright, cup-shaped, and often dark purple at the base.

　　The scape is 35 to 55 cm long; the flowers are solitary, erect, 5 to 7.5 cm long; there are 6 petals, obovate, bright yellow or purple-red, with yellow stripes and spots: 6 stamens, free, anthers 0.7 to 1.3 cm long, attached at the base, filaments broad at the base; pistil 1.7 to 2.5 cm long, style 3-lobed to the base, recurved.

　　The flower shapes include cup, bowl, egg, ball, bell, funnel, lily, etc., with single or double petals. The flower colors include white, pink, magenta, purple, brown, yellow, orange, etc., with different shades, single or multiple colors.

　　Growth habits Tulips are native to Xinjiang, Tibet, Iran, and the high mountains of Turkey. Due to the Mediterranean climate, tulips are adapted to cold and wet winters and hot and dry summers. They are dormant in summer, take root in autumn and winter, and sprout new buds, but do not emerge from the ground. After the low temperature in winter, they begin to grow and form stems and leaves in early February of the following year (temperature above 5°C), and bloom in March and April. The optimum temperature for growth and flowering is 15 to 20°C. Flower bud differentiation occurs when the bulbs are dug out of the pot when the stems and leaves turn yellow and placed outdoors in a cool and shady place to spend the summer. The optimum temperature for differentiation is 20 to 25°C, and the maximum temperature should not exceed 28°C.

　　Tulips are long-day flowers that prefer sunny, wind-proof, warm and humid winters and cool and dry summers. They can grow normally above 8°C and can generally withstand low temperatures of -14°C. They are very cold-resistant. In cold areas, if there is thick snow, the bulbs can overwinter in the open field, but they are afraid of extreme heat. If summer comes early and midsummer is very hot, it will be difficult for the bulbs to survive the summer after dormancy. They require slightly acidic sandy loam that is rich in humus, loose and fertile, and well-drained. Avoid alkaline soil and continuous cropping.

　　Flowering period regulation Tulips are cold-resistant but not heat-resistant. They can generally withstand temperatures as low as -30°C and will go dormant in hot seasons. They usually prefer moist, cool climates and environments that are sheltered from the wind and face the sun. They grow better in neutral or slightly acidic soils. A mature tulip bulb contains three generations of bulbs, or three generations of bulbs. The large bulb itself is the first generation of bulbs, which have fully differentiated flower organs and bloom in the same year after planting. The second and third generation bulbs are daughter bulbs, which can be cultivated into large bulbs. Tulip bulbs must be subjected to a certain low temperature before they can bloom. In their place of origin, there is generally sufficient low temperature time in winter. Tulip bulbs can get enough low temperature treatment time and can bloom naturally in spring. Generally speaking, the tulip bulbs used in production are treated at 5°C and 9°C. The main planting methods after treatment are greenhouse cultivation and box-based forced cultivation. Tulip cultivation in southern regions such as South China is limited by temperature and is planted within three months from December to February of the following year. In December, the temperature in South China may still be very high. At this time, tulips can be cultivated in cultivation boxes and placed in a cold storage at about 5℃ for 2 to 3 weeks. When the bulbs of tulips have grown roots and the buds are about 1 cm to 2 cm long, they can be moved out of the cold storage and placed in a planting shed for growth. The cultivation of tulips in South China is greatly affected by the climate. Tulips are sensitive to temperature. If there is a "warm winter" in South China, a large number of tulips will often bloom early, and the quality of the flowers will also be greatly affected. In order to ensure that tulips can bloom on time, the daytime temperature should be kept at 17℃-20℃ and the nighttime temperature should be kept at 10℃-12℃ during the growth period. When the temperature is high, the temperature can be lowered by shading and ventilation. When the temperature is too low, it can be promoted by heating and increasing light. Using water control to inhibit growth will cause the phenomenon of "dry flowers". If the temperature continues to be high, the boxes can be moved into the cold storage. Note that the temperature of the cold storage should be around 8℃-10℃, and it is best to move it in when the flower stems are growing, otherwise it is easy to cause poor development of the flower buds. The flowering period of tulips can also be controlled by plant growth hormones. For example, soaking tulip bulbs in gibberellins can make them bloom in a greenhouse and increase the diameter of the flowers.

[Classification by color] 1. Tulip (red) Tulipa gesnerianna Tulip is the national flower of the Netherlands. The period from 1634 to 1637 was called the "Tulip Mania" in Dutch history. New and rare varieties of tulips were sold at high prices and became the investment objects that people competed for. Flower language: Confession of love Flower gifting etiquette: Place a few red tulips on a square of hard backing paper, fix the position with tape, carefully wrap them with transparent plastic paper, and decorate the four corners with golden ribbons to add a sense of magnificence. 2. Tulip (yellow) Tulipa gesnerianna Tulip is a genus of the lily family. In Europe and the United States, yellow flowers are usually not very popular, and the related flower language also has a relatively negative connotation. In fact, the clear yellow color implies the joy of spring. How can people not like the eye-catching bright flowers? Flower language: Hopeless love Flower gifting etiquette: Because the flower stems of tulips are quite curvy, it is appropriate to use slightly larger wrapping paper with white background patterns, and tie 4 to 5 long tulips into a bunch. The ribbon must be yellow. 3. Tulip (white) Tulipa gesnerianna Liliaceae Tulipa genus When the Australian ambassador who came to Turkey in the 16th century saw this flower for the first time, he asked the Turkish people around him its name, and the answer was: tulip. In fact, this pronunciation refers to the Turkish headscarf. The Turkish people misunderstood the ambassador's meaning, but the name of the flower was created and used. Flower language: Lost love Flower gifting etiquette: Just use a few white tulips to make a bouquet, without adding other embellishments. Whiten the outside with pink tulle, and then gently tie it with a few red thin ribbons.

　　8. Propagation and cultivation usually use bulb division, mainly by separating small bulbs. In autumn, the small bulbs are divided in September and October. The mother bulb is an annual, that is, it is renewed every year. After flowering, 1 to 3 new bulbs and 2 to 6 small bulbs that can bloom the next year develop at the base of the bulb, and the mother bulb dries up. A new bulb and several daughter bulbs grow in the scales of the mother bulb. The number of daughter bulbs varies depending on the variety and the cultivation conditions. The expansion of the new bulb and the daughter bulb is usually completed within one month after flowering. The dormant bulbs can be dug up in early June, the mud is removed, and stored in a dry, ventilated place with a temperature of 20 to 22°C, which is conducive to the differentiation of bulb flower buds. The daughter bulbs separated from the large bulbs are stored in a ventilated place at 5 to 10°C and planted in September and October in autumn. Sufficient leaf mold and appropriate amounts of phosphorus and potassium fertilizers should be applied to the cultivation site as base fertilizer. After planting the bulbs, cover them with 5 to 7 cm of soil. Sow in the open field in autumn, with a depth of 1 to 1.5 cm. The number of bulblets produced in the scales of the mother bulb varies with the variety and is also related to the cultivation conditions. They can germinate in the next spring and bloom in four to five years. The expansion of new bulblets and bulblets is usually completed within one month after flowering.

　　Conventional cultivation of tulips requires well-drained sandy soil, pH 6.6-7, deep tillage, basal fertilizers such as decomposed cow dung and leaf mold, and a small amount of phosphorus and potassium fertilizers. Planting is done in ridges with a planting depth of 10-12 cm. Topdressing is generally done after germination, bud formation and flowering. The bulbs take root in winter, and topdressing is done twice before flowering in spring. It blooms from the end of March to the beginning of April, and the leaves on the ground turn yellow and enter dormancy in early June. It is generally not necessary to water during the growth process, just keep the soil moist, and water it appropriately during droughts. The key points of its cultivation and management are basically the same as those of hyacinths; it is just that tulip varieties are prone to hybridization and the varieties are mixed, so attention should be paid to isolated planting. Tulip bulbs contain a lot of starch and are easily eaten by mice during storage, so they should be carefully collected. Tulips are bulb plants, which need to go through a certain low temperature stage and bloom normally after the flower stems are fully grown. Conventional cultivation is a general cultivation method, which is a cultivation method without cold treatment of tulip bulbs. 1. Preparation before planting Before planting tulips, a complete production plan needs to be formulated, including the selection and arrangement of the planting site, how to obtain the production tools for tulip bulbs, and the preparation of potting soil and containers for potted plants. Tulip bulbs should be planted in deep, fertile sandy soil. Waterlogging is the most taboo for the growth of its root system, and the selected terrain must have smooth drainage. The planting bed is generally 30 cm wide and the trench depth is deeper in flat areas. If the soil is sticky in the first year of planting, two cubic meters of peat and 5 kg of compound fertilizer can be used as base fertilizer for every 100 square meters to improve the soil. Tulips are not suitable for continuous cropping. It is best not to plant tulips on the land that has been planted with tulips in the previous one or two years. One month before planting tulips, the land should be deeply plowed and exposed to the sun to eliminate pathogenic spores and remove weeds. Then choose sunny weather and irrigate with 100 times 40% formalin solution (depth of more than 10 cm). After the soil is disinfected, cover it with a film for about a week. After removing the film, make the soil fine and prepare for planting. 2. Planting Plant in sunny and well-drained sandy loam. Generally, planting can be considered when the soil temperature is stable below 12℃. After deep plowing, it is advisable to apply decomposed cow dung and other phosphorus and potassium fertilizers (7-10 grams of phosphorus pentoxide and 13-15 grams of potassium oxide per square meter). The depth of soil is about 2 times the height of the bulb, and the spacing between rows is 2-3 times the horizontal diameter of the bulb. After covering the soil, no watering is required, but straw must be added to increase soil moisture and prevent soil compaction. Apply a thin nitrogen fertilizer once before the young buds emerge and unfold leaves; increase the fertilizer concentration (10% fertilizer and 90% water) after buds appear. Generally, no watering is required during the growth period, as long as the soil is kept moist. If the weather is dry, water it 1-2 times (the moist depth is about 15 cm). For cut flowers, they should be cut when the buds are completely changed in color, and the ornamental period of vase insertion is about 10 days. The bulbs should be disinfected before planting. They can be immersed in potassium permanganate solution or formalin solution for 30 minutes and planted after drying. The density of productive planting can be controlled at 12×12 cm or 13×12 cm, which varies slightly according to the variety. Generally, varieties with strong upright leaves and short plants can be planted densely. If it is an exhibition planting, it can be placed at 20~25 cm, and the planting depth is 4~5 cm from the top of the bulb to the soil surface. Water thoroughly after planting to prevent drying and dehydration. Tulips are mostly potted for viewing, as ground cover plants and for medicinal purposes.

　　9. Maintenance Tips Tulips are cold-resistant and can withstand temperatures as low as -35°C in winter. They can also grow normally at 5°C to 8°C, making them suitable for winter forced cultivation. Tulip forced cultivation means breaking the dormancy of flower and leaf primordia, eliminating factors that inhibit flower bud germination, and promoting flower bud differentiation through temperature changes on bulbs. Then, artificial warming and light supplementation are used to make tulips bloom in non-natural flowering periods. Currently, 5°C bulbs and 9°C bulbs are common on the market. We generally choose 5°C bulbs for forced cultivation of flowering during the Spring Festival.

　　[Substrate preparation] First of all, we need to prepare a high-quality substrate that is both water-retaining and breathable. The salinity should not be too high or too acidic, the pH value should be no less than 6, and there should be no pests or harmful substances. The bulbs should be planted firmly in a sufficiently deep (at least 5 cm deep) cultivation bed. In recent years, we have used peat, rotted soil and sand in a 1:1:1 mixture as the cultivation substrate, and the effect is good. About half a month before planting, apply rotted farmyard manure to the bed soil as base fertilizer, and add an appropriate amount of furadan and carbendazim (or use 1% formalin for irrigation and disinfection), irrigate fully, and carefully plow and harrow before planting to ensure that the soil is loose.

　　〖Planting〗 Due to the high temperature in the greenhouse, tulips will experience late spring, and the effect of low temperature treatment for forcing cultivation will be reduced. Therefore, early planting is not as good as late planting. Generally, it is planted about two months before the Spring Festival, around the beginning and middle of November. Before planting, remove the brown bulb skin and soak it in 500 times 50% carbendazim solution for about two hours. The spacing between plants and rows is 9×10cm. When planting, the top of the bulb should be level with or slightly lower than the soil surface. Appropriate shallow planting can promote early flowering. Sometimes, tulip bulbs can bloom more than 5 days earlier when about 1/3 of the bulb is exposed above the soil surface. Water thoroughly after planting to promote rooting.

　　The cultivation and management temperature is generally one week later, and the bulbs begin to germinate. In the pre-seedling and seedling stage, keep the indoor temperature at 12℃~15℃ during the day. If the temperature is too high, timely ventilation and cooling should be carried out. The temperature should not be lower than 6℃ at night to promote the early rooting of the bulbs, strengthen the roots, and cultivate strong seedlings. At this time, the temperature is too high, which will make the plant stems weak and the flower quality poor. After more than 20 days, when the plant has grown two leaves, the temperature should be increased in time to promote the flower buds to separate from the bracts in time. The indoor temperature should be maintained at 18℃-25℃ during the day and above 10℃ at night. Generally, after more than 20 days, the corolla begins to color. The first flower blooms in late December to early January, and it takes 10~15 days to reach the peak flowering period. At this time, it should be placed in batches according to the different time required for flowering. The higher the temperature, the earlier the flowering. Generally, after the corolla is fully colored, the plant should be placed in an environment of 10℃ for sale. Sufficient light is necessary for the growth of tulips. Insufficient light will cause poor plant growth, bud drop, plant weakness, lighter leaf color and shortened flowering period. However, within half a month after the tulips are potted, they should be properly shaded to facilitate the growth of new roots in the bulbs. In addition, during germination, the elongation of flower buds is inhibited by light. Shading can promote the elongation of flower buds and prevent excessive vegetative growth and leggy growth in the early stage. After germination, light should be increased to promote plant jointing, form flower buds and promote coloring. After the flower buds are fully colored in the later stage, they should be protected from direct sunlight to extend the flowering time. Fertilization: Since the substrate is rich in organic fertilizer, no topdressing is required during the growth period. However, if the leaf color becomes lighter or the plant is not strong enough due to insufficient nitrogen, easily absorbed nitrogen fertilizers such as urea and ammonium nitrate can be applied. The amount should not be too much, otherwise it will cause leggy growth and even affect the plant's absorption of iron, resulting in iron deficiency (when iron is deficient, all new leaves and flower buds turn yellow, but old leaves are normal). The effect of topdressing liquid fertilizer during the growth period is significant. Generally, potassium dihydrogen phosphate solution with a concentration of 2‰~3‰ is sprayed once every 10 days from budding to flowering to promote large and colorful flowers and firm and upright flower stems. Water: After planting, water should be poured thoroughly so that the soil and bulbs can be fully and tightly combined to facilitate rooting. After budding, water should be properly controlled. When the leaves gradually elongate, water can be sprayed on the leaves to increase air humidity. Adequate water supply should be ensured during the flower stalk and budding period to promote full development of flowers. After flowering, water should be properly controlled. Pest and disease control The pathogens of tulip pests and diseases can be carried by bulbs or carried by soil to infect bulbs. They often occur in high temperature and high humidity environments. The main diseases are stem rot, soft rot, broken color disease, damping-off disease, blind buds, etc. The pests are mostly aphids. Prevention and control methods: Thoroughly disinfect the soil before planting, use detoxified bulbs as much as possible, dig out and destroy diseased plants in time, and water 1 to 2 times of fungicide during greenhouse growth for better results; good ventilation should be maintained to prevent high temperature and high humidity; when aphids occur, 3% natural pyrethroids can be sprayed at 800 times. Others 1. Potted tulips are directly potted and managed. Due to the different quality of bulbs, the growth and flowering are uneven, which affects their commodity quality. Therefore, it is best to plant them in the greenhouse first, and then pot them after their corollas are colored, which does not affect their flowering quality and has better results. 2. Among the flower colors, red blooms the earliest and yellow blooms the latest, about 10 days apart. During cultivation, the planting time should be staggered appropriately to ensure simultaneous flowering.

　　10. Cutting and preservation Cutting and preservation of cut flowers: Cutting and preservation of cut flowers: When the buds are fully colored, they can be cut and put on the market. If they are managed at a slightly lower temperature, they can gradually color; but if they are used at a high temperature to bloom early, the coloring is poor. At the same time, those that color late are easily damaged during transportation and market transactions. Therefore, when it is close to flowering, it is necessary to avoid excessive temperatures, and to maintain good ventilation while providing adequate shading. It is easy to pull up the bulbs when cutting flowers, so you can use pliers to cut them and keep the stems inside the bulbs as much as possible. Cut flowers are sorted according to variety, plant height and flower size, and shipped in bundles of 10. For vase preservation, a mixture of 10×10~6 benzyl ammonium chloride, 2.5% sugar, and 10×10~6 calcium carbonate can be used, or a mixture of sugar, chlormequat and 8-hydroxyquinoline citrate can be used.

　　11. Post-harvest technology 1. Main characteristics of cut flowers: The longer the cultivation time is promoted by low temperature at night, the longer the vase life of cut flowers. 2. Harvest and development stage: The best harvest period for tulips varies from variety to variety. Generally, the flowers are harvested when 1/2 of the flowers are colored. Immediately after harvesting, place them in an environment with a temperature of 2°C and a relative humidity of at least 85%. 3. Vase life: The short vase life is only 3~4 days, and the long vase life is about 5~7 days. 4. Treatment method of preservatives: The preservative liquid causes the flower stems to elongate too long, which has little effect on extending the vase life. Therefore, the preservative liquid is generally not used. 5. Storage and transportation technology: It can be stored dry (horizontally) or wet (vertically) at a temperature of 2°C, and the flower heads are tightly wrapped with plastic film, but it is not suitable for long-term storage. Some varieties are harvested together with the bulbs at the green bud stage and can be stored at 0°C for 2~3 weeks. 6. Treatment for Retailers and Consumers (1) Re-cut the flower stems, place the cut flowers in 15-20 cm deep water, wrap the flower heads with plastic film, and hydrate at room temperature until the cut flowers are firm. (2) Cut flowers should be stored at 2°C for the longest life in a vase. (3) Cut flowers should be placed in a cool, windless environment, not near a stove. Tulips are phototropic, so the light in the room should be evenly distributed to avoid bending the stems. (4) Do not place tulips and daffodils in the same container, otherwise the life of the tulips will be shortened. Tulips may cause redness and swelling on the palm of your hand, so be careful when handling them.

12. Disease prevention and control [Prevent bulb rot] Bulb rot often occurs in tulip cultivation. The main reasons are: the bulbs are not dried out and are attached with soil with pathogens. The temperature and humidity during storage are high, which is suitable for the reproduction and spread of pathogens, causing the bulbs to rot; soil with pathogens (mostly Fusarium) and fertilizers that are not fully decomposed are used during cultivation, which causes the bulbs to rot due to pathogens; the potting soil is clay soil, and excessive watering causes water accumulation in the potting soil, causing the bulbs to rot due to waterlogging; the bulbs are dug up too early, and the new bulbs do not grow well, which is also easy to cause rot. The method to prevent bulb rot is to take corresponding measures according to the above-mentioned pathogenic factors.　

　　[Pest and disease control] The main pests and diseases of tulips include rot, sclerotinia, virus disease, thrips, eggplant aphids and root lice. After sclerotinia disease, yellow or brown slightly raised round spots appear on the scales, and sclerotia are produced in the slightly concave part inside. The pathogen infects the stem to produce oblong lesions and sclerotia on the surface. Prevention and control methods: First, disinfect the soil before planting; second, remove the diseased plants immediately after the disease occurs and spray 500 times dilution of mancozeb. Viral disease Viral disease is one of the main reasons for the degradation of tulip germplasm. There are many viruses that harm tulips, and the most common ones are mosaic virus and broken color virus. Mosaic virus causes yellow stripes or granular spots on the affected leaves, dark spots on the petals, and leaves rot in severe cases. Pay attention to timely prevention and control of aphids and weeds. Broken color virus causes light yellow or grayish white stripes or irregular spots on the diseased leaves, sometimes forming mosaic leaves, light yellow or white stripes or irregular spots on the petals, and broken color flowers on red or purple varieties. Its prevention and control methods are the same as general viral diseases, but the planting site should be far away from lilies. Rot disease This disease mainly harms tulip bulbs and plants. After the bulbs are infected, water-soaked brown spots begin to appear, and then the bulbs become soft and rotten. After the plants are infected, the tips and edges of the lower leaves fade, the stems turn purple, and the base of the stems shrink, and the plants eventually die. Prevention and control methods: When storing bulbs, they cannot be exposed to high temperatures and high humidity, and attention should be paid to ventilation to avoid continuous cropping. Diseased plants and diseased bulbs should be disposed of in time. Spray with 1000 times 70% thiophanate solution in time at the early stage of the disease. Root lice eat bulbs in the soil, drill into the epidermis to suck juice, causing the plants to grow weak or easy to rot or induce diseases. Soak the insect-infected bulbs in dilute lime water for 10 minutes, take them out and rinse them to kill the root lice.

　　[Main diseases]

1. Symptoms of tulip white rot: the whole plant wilts, the stem base is wrapped with white mycotoxin or rapeseed-like dark brown sclerotia, and the affected part turns brown and rots. A large number of white mycotoxin and dark brown fungi can be seen on the soil surface. Pathogen: Sclerotiumrolfsii Sacc. is also called neat small sclerotia, belonging to the subphylum Ascomycota. The hyphae are white and silky, fan-shaped or radially expanding, and then aggregate into mycotoxin or tangled into mycotoxin. The mycotoxin is like rapeseed, white to yellow-white at first, then turns dark brown, round, and has a smooth surface. In addition, it has been reported that Corticiumrolfsii (Secc.) Cyrzi. is also the pathogen of this disease. Transmission route 1. The pathogen overwinters in the soil with sclerotia or mycotoxin along with the diseased body. When the conditions are suitable the following year, the mycotoxin produces filaments in the mycotoxin to cause initial infection. 2. The silky hyphae produced by the plant extend to contact the neighboring plants or the sclerotia to spread through water flow for re-infection, so that the disease spreads and spreads. The disease is serious in years or seasons with continuous cropping, heavy soil, low-lying terrain, high temperature and humidity. Prevention and control methods: When the diseased plants are found, they are promptly removed and burned. The diseased holes and the neighboring plants are irrigated with river water with 1000~1600 times of 5% Jinggangmycin aqueous solution, or 500~600 times of 50% Tianan aqueous solution, or 1000 times of 20% methyl tolclofos emulsion, or 500 times of 90% dichlorvos wettable powder. Each plant (hole) is sprinkled with 0.4~0.5 liters. Combined with turning the soil, 100~150 kg of lime powder is added per mu to make the soil slightly alkaline, which can inhibit the reproduction of white rot fungi. 2. Symptoms of tulip brown spot disease: The infected leaf buds are poorly developed and are deformed and curled. The leaves that grow after the young buds are damaged become curled. If the environment is humid, a large number of gray mold-like conidia will be produced on the diseased tissue, which will affect the adjacent healthy plants and make the leaves infected, so the growth of the bulbs will be greatly affected. After the flowers are infected, white or light yellow-brown spots begin to appear, and then they quickly wither or turn brown and dry up. Ring-shaped bands will appear on the pedicels, and sometimes conidia will occur on them. The disease is very easy to infect flowers at every stage. Sclerotia grow on the outer shell of the diseased bulb, or round or oval concave spots appear on the outer scales, with a gray-yellow center and brown edges, containing one to several sclerotia. Pathogen: Tulip grape [BotrytistulipaeLind.] belongs to the subphylum Ascomycota, which is common in tulip cultivation areas and is more serious in the rainy season. Transmission route: Mycelium and sclerotia remain in rotten bulbs and soil to overwinter. After the diseased bulbs are planted, a large number of conidia are produced on the young shoots of the infected dead bulbs, which is the source of infection for the aboveground diseases. Disease conditions: The pathogen can produce conidia at 5 degrees and humidity of 90% to 100%. The disease is more serious in spring when the temperature is low and the weather is rainy and humid. Prevention and control methods 1) Remove the diseased bulbs before planting and implement rotation planting. 2) Once buds or flower buds showing symptoms of the disease are found, remove them immediately to control the development of the disease. 3) Soak the bulbs in 2% formalin solution for 30 minutes before planting, dry them and plant them to reduce residual pathogens. 4) Spray 50% chlorhexidine 1000 times solution or 50% prochlorperazine 2000 times solution or 50% polymyxin 1000 times solution during the growing season. 3. Tulip black rot symptoms: The bulbs are diseased. Irregular spots that are initially yellow-brown and then black are produced on the stem disk and stem surface, sometimes on the second and third scales, and the surface is rough. Pathogen: Pseudomonas adenophora (Smith) Stapp. The bacteria are rod-shaped, with a minimum size of 1.9*0.8 microns, and 1~3 flagella at the pole. The optimum temperature for the disease is 20~25 degrees, with a minimum of 5 degrees. Transmission route: Infected bulbs and diseased residues in the soil are the source of infection. Prevention and control methods: Try to soak the bulbs in agricultural streptomycin sulfate solution for disinfection. 4. Tulip mosaic disease (CMV) Symptoms: Mosaic pattern and chlorotic stripes appear on the leaves, sometimes necrotic spots appear, and dark spots appear on the petals. Growth and development are inhibited. When the symptoms are severe, the bulbs will not grow large and the damage is serious. Pathogen: Cucumber mosaic virus (CMV). Transmission route: The virus occurs in many crops and weeds, and is transmitted by aphids in a non-persistent manner. Prevention and control methods: 1) Use healthy bulbs. 2) Control aphids in time. 5. Tulip wilt symptoms: Dark brown and gray concave spots appear on the scales on the outside of the bulb, and then expand to become medium dark brown spots. If the diseased bulbs are placed in a warm and humid place, white or pink hyphae and conidia will grow on them, causing the infected tissue to shrink and harden. After the base of the scales is damaged, the rapidly developing lesions can spread all over the scales. The ethylene produced by the diseased scales will cause the healthy bulbs to have gum flow, affecting growth. The leaves on the bulbs show premature aging, and some leaves are upright and gradually turn into a unique purple color. The flowers that grow are thin, deformed, and even withered. If in a greenhouse, the infected plants will chlorosis and die early. Pathogen: Tulip Fusarium oxysporum Sch1.f.sp.tulipae Apt. Microspores are 5~12*2.2~3.5 microns, and the megaspores have 3~5 septa and are 30~60*3.5 microns in size. Prevention and control methods: 1) Delay planting appropriately, dig the bulbs in advance, and avoid high temperature periods as much as possible to prevent the rampant harm of the pathogen. 2) Healthy bulbs should be stored separately in a ventilated and cool place (below 15 degrees). 3) Do not plant too densely. If diseased plants are found during the growth period, they should be removed in time. 4) Within 48 hours of digging out the bulbs, soak them in a 50% benlate wettable powder water solution for 15 to 30 minutes, dry them and store them. 5) Plant disease-free bulbs and implement a three-year rotation system. 6. Symptoms of tulip broken petal disease: The main symptoms are manifested on the flowers. The color of the petals on the same flower changes in different shades, some colors deepen, some colors remain normal, and some colors become lighter. Some broken petals are mottled, and some are striped. The affected leaves have lighter spots or stripes, and the anthocyanin pigments on the outer side of the first leaf of many varieties show irregular stripes. Pathogen: Tulip Breaking Virus (TuBV), the lethal temperature of the virus is 65 degrees to 70 degrees. Transmission route: The sclerotia overwinter and summer in the bulbs and soil. The virus is transmitted by aphids during the growth period. Knives and scissors used for cutting flowers can also be infected. Prevention and control methods: 1) Select non-toxic plants as propagation materials. 2) Remove diseased plants in time. 3) Spray 40% dimethoate EC 1000 times diluted, or 40% oxydemeton EC 1000 times diluted, or 2.5% dervine extract 800 times diluted to control aphids. 4) When cutting flowers, knives and scissors should be heated and disinfected or washed with detergent before use.

13. Related issues

What causes blind branches and flowers of tulips? Tulips are perennial bulbous herbaceous plants belonging to the lily family and the genus Tulip. They have an upright plant shape, large and gorgeous flowers, and high ornamental value. However, if not properly cared for, tulips are prone to blind branches and flowers. The symptoms of blind flowers are that the branches and leaves develop normally. For those with weak growth, the flower buds lose water and become white, the leaves are pointed, and the flower stems shrink; for those with strong growth, the flower stems are short, the petals remain green or white, and curl together with the stamens and pistils, and cannot fully open. Blind branches refer to plants with only one fat leaf on the aboveground part, no leaf branches, and no flower branches. The reasons for its formation are as follows: 1. Related to varieties, biological characteristics and cold treatment time: Due to the long-term tempering of harsh natural conditions in the place of origin, tulips not only have the variety characteristics of cold resistance and heat resistance, but also have the biological characteristics that they must undergo a certain period of low temperature treatment and the stems and leaves must be fully grown before they can bloom. In the northern region, open-field planting in autumn and winter can meet the low temperature requirements, and bloom in April and May of the second year. Taking advantage of this characteristic, tulip bulbs can be treated at 9℃ or 5℃ for forced cultivation, and flowers can be provided all year round. The blind flower phenomenon in production is mainly caused by the bulbs not being vernalized at low temperature or the short cold treatment time, which does not meet the flowering requirements. 2. It is related to the size of the bulbs and the intermediate temperature: In production, bulbs over 12 cm are mostly used as bulbs. The flower buds of such bulbs are fully developed, and there are no blind flowers. Bulbs with bulbs below 10 to 11 cm are mostly planted in the open field. After one year, the flower buds can bloom normally after they are fully developed. If forced cultivation is used, the blind flower rate is higher. This is mainly because most of the flower buds of bulbs of this size have not yet fully developed. Before cold treatment, the treatment time must be extended by 1 to 3 weeks compared with bulbs with a diameter of 12 cm at an intermediate temperature of 17℃~20℃. If the bulbs are of different sizes, the intermediate temperature treatment is improper, and forced cultivation is used, blind branches and blind flowers are prone to occur when the fertilizer supply is insufficient during vegetative growth. Therefore, producers are reminded to strictly select bulb specifications according to different cultivation methods in mass production. 3. Influence of human factors: First, when removing the bulb skin before planting, try not to lose the stem buds to reduce the occurrence of blind branches. Secondly, during storage and transportation, artificially create extremely high temperatures, such as: excessive heat dissipation of the bulb itself or other fruits, vegetables, flowers and engines, causing the production of ethylene in the bulb. When the ethylene concentration reaches 0.1dpm, the buds will be necrotic, and a large number of blind branches will appear after cultivation. 4. Influence of other factors: such as improper watering during cultivation, excessive humidity in the greenhouse, and root suffocation caused by diseased bulbs, there will be no yield. How to pot tulips? Tulips can be planted in the ground or in pots. Cultivation time, both methods can be carried out in late October. The spacing between rows and plants for ground planting is 14~16 cm, sufficient base fertilizer is applied, the soil depth is about 4 cm, the trench depth is 15~20 cm, and water is applied after planting. Apply thin fertilizer 2~4 times before and after germination and flowering. For potted plants, choose full and plump bulbs. 3 to 5 bulbs can be planted in a 30 cm pot. The top of the bulb is flush with the soil surface. After planting in autumn, bury the pot in the soil, dig it out in spring, place it in a sunny and well-ventilated place, water and fertilize it normally, and it will bloom on time. Experience in cultivating tulips? 1. It requires good drainage and sandy loam with a lot of humus. A small amount of fermented manure and bone meal can be mixed in as base fertilizer. 2. It likes coolness, but has strong adaptability. It can face both wet and cold winters and dry and hot summers. However, it should not exceed 27℃ in summer. Too high temperature will cause the leaves to grow too long, the proportion of leaves and flowers to be unbalanced, and the flowering is poor; the suitable temperature for growth is 15~20℃, and it can grow normally above 8℃, but it can also withstand low temperatures of -14℃. 3. Generally, it is sufficient to keep the plant moist during the growing period. Except for watering in drought, it is generally not necessary to water it in large quantities. In winter, the plant mainly grows roots and grows slowly, so it can be watered less or not at all. In spring, the plant is in the vigorous growth period of flower buds and leaves, so it can be watered in moderation. After the flowers fade, the main focus is on growing bulbs, so watering should be properly controlled. 4. The flowers can only bloom well if there is sufficient light, and the viewing period of flowers can be extended. Insufficient light will result in insufficient opening or even closed flowers. 5. During important growing periods such as after germination, during the bud formation period, and after flowering, topdressing should be carried out. Diluted solutions such as sesame paste residue, horseshoe water, and ferrous sulfate can promote their growth. Urea should not be used for topdressing. 6. For those who want to grow bulbs, the flower buds should be removed immediately when they are colored to avoid nutrient consumption. For those who want to produce cut flowers, the flower buds can be cut off when they are completely discolored. 7. If the flowers have patterns, it is caused by virus infection and should be dug out and burned immediately to avoid the spread of infection. 8. Reproduction: Seed propagation is generally used in breeding and mass reproduction. However, it takes 4 to 5 years to bloom, so it is generally based on separating small bulbs. The method is as follows: the one-year-old mother bulb will sprout 1 to 3 new bulbs and 2 to 6 small bulbs that can bloom the next year at the base of the bulb after flowering, while the mother bulb will gradually dry up. The bulb can be dug out, the soil removed and dried, and the bulblets on the bulb can be separated and stored in a ventilated place at 5 to 10°C; in September in autumn, the bulblets can be planted in soil rich in leaf mold and appropriate phosphorus and potassium fertilizers, with a row spacing of 14 to 16 cm, a trench depth of 15 to 20 cm, and a soil covering depth of 4 cm; but it should be noted that if the bulblets are round, they can bloom even if they are small, but if the bulblets are flat, they generally will not bloom; after planting the bulblets, they should be watered thoroughly and kept moist at ordinary times. In the following spring, normal fertilizer and water management of the seedlings will begin, and they will bloom in 2 to 3 years. 9. Forcing cultivation: To supply the needs of the Spring Festival, early flowering varieties can be selected. Plant them in hotbeds or the light-receiving side of greenhouses in early October, move them into greenhouses in early December, sprinkle water once a day, and buds will appear in about 20 days. If you want to advance, the greenhouse temperature should be maintained at 16~18℃, and cover them on all sides to prevent them from seeing the sun. After two weeks, place them in a sunny place and cool them down appropriately. They will bloom after six weeks. How to produce tulips hydroponically? Tulips are perennial herbs of the Liliaceae family. They are popular because of their large flowers and bright colors. Due to their popularity in the market, countries have devoted themselves to studying their cultivation techniques, and hydroponic cut flower production has gradually become popular among professional growers. Introduced and tested cultivation began in the 1990s. The current domestic hydroponic experience is mainly: 1. Selecting suitable and disease-free bulbs is the key to the hydroponic production of tulip cut flowers. 2. After the bulbs are transported back, they must be stored in a well-adjusted cold storage with a temperature of 5℃ and a humidity of less than 80%. Check and select bulbs with serious penicillium disease in time. 3. Select and determine the cultivation time and planting method according to the time required. For hydroponic cut flower cultivation, the bulbs should be planted in a sterilized and watertight needle tray, so that the rooting temperature is stable at 8℃ and the humidity is between 60% and 70%. 4. After about two weeks of rooting, ensure that the root length is more than 3 cm, and transport the needle tray to the greenhouse. The temperature is controlled at 15℃ to 20℃, the humidity is 60% to 70%, and the nutrient solution is added to make the Ec value in the water 1.5ms to 2.0ms, so as to facilitate the rapid growth of tulips. 5. In the early stage of growth, in order to prevent diseases caused by filamentous fungi, spray 2 to 3 times. The low-toxic and high-efficiency agents are selected, such as chlorothalonil, thiophanate-methyl, and thiophanate-methyl, with a concentration of 750 to 1000 times. 6. Spray foliar fertilizer in time according to the growth situation to coordinate vegetative growth and reproductive growth. 7. During the growth process, due to the secretions of the roots and other environmental conditions, a layer of oil film will form on the surface of the water in the needle tray, which will cause the roots to lack nutrients and turn brown. Therefore, change the water 2 to 3 times depending on the situation. 8. When the finished cut flowers are harvested but not sent away in time, they must be placed in a cool and ventilated place to avoid strong light, high temperature or low temperature that may affect the quality of the cut flowers.

　　14. Harmful and toxic flowers contain toxic alkali. You will feel dizzy after staying with them for one or two hours. In severe cases, it may lead to poisoning. Excessive contact may cause hair loss.

　　15. Flower language Tulip language: fraternity, thoughtfulness, elegance, wealth, ability and intelligence Red tulips represent passionate love Pink tulips represent eternal love, beauty, passion, cherishment and happiness Yellow tulips represent cheerfulness, elegance, preciousness, wealth and friendship Symbolizes holiness, happiness and victory White tulips represent pure and noble love Broken heart and hopeless love Black tulips represent unique leadership power, love confession, crown of honor, mystery, nobility and eternal blessing Purple tulips: noble love, endless love, loyal love Plateau tulips: pride, uprightness, creative beauty, creation of beauty In European and American novels and poems, tulips are also regarded as a symbol of victory and beauty, and can also represent elegance and grace [1]. II. Materia Medica Curcuma Curcuma is bitter, cold and pure yin. Non-toxic. Enters the heart, lung and liver meridians. It is an important medicine for blood. It can also relieve depression and relieve stagnant qi, so it is necessary to treat depression. However, it should not be used lightly. Because of its cold smell, it damages the vitality of the stomach, and the depression may not be relieved, and the stomach qi will be weak first, which is a loss of the way of health preservation. As for breaking blood, prohibiting blood, and stopping bleeding, they are also temporary expedients, and they will be used as long as the disease is cured, but they cannot be relied on for daily home use. 3. Application value [Ornamental value] Tulip flowers are like lotus flowers, with a variety of colors, rich and bright colors. They are important spring bulb flowers. Dwarf varieties are suitable for arranging spring flower beds, which are bright and eye-catching. Tall stem varieties are suitable for cut flowers or flower borders, and can also be planted in clusters on the edge of the lawn. Medium and short varieties are suitable for potted plants, embellishing courtyards, indoors, cut flowers, potted plants, etc., to add a happy atmosphere.

　　Warning: Tulip bulbs are toxic. If eaten by mistake, they can cause vomiting and diarrhea. Contact with its leaves may also cause allergic symptoms on some people's skin. Therefore, even if used as medicine, please use it strictly according to the doctor's instructions. 4. The national flower of the Netherlands - tulips Tulips originally grew on the Qinghai-Tibet Plateau. They were introduced to Europe from Turkey in 1554 and became popular immediately. In the 17th century, they became the target of crazy financial speculators in the Netherlands. Someone also made up a story: In ancient times, there was a beautiful girl living in a majestic castle. Three warriors fell in love with her at the same time. One gave her a crown; one gave her a sword; and one gave her a pile of gold. But she didn't fall in love with anyone, so she had to pray to the flower god. The flower god felt that love could not be forced, so he turned the crown into flowers, the sword into green leaves, and the gold into bulbs, which together became tulips. In order to express love to young boys and girls on Valentine's Day every year, in addition to roses, tulips have become the best choice to convey their feelings to their lovers. This story has deepened the Dutch people's impression of this flower. There is even a propaganda media that spreads a motto: "Whoever despises tulips offends God." Tulip fever finally swept the Netherlands and even Europe. Many people believe that "a rich man without tulips is not really rich." Some people would rather exchange a winery or a house for a few rare seeds. In 1637, the Dutch tulip market collapsed, and the government intervened to prevent further speculation. During the crazy speculation period, the number of tulips in the financial market exceeded the number of actual plantings, but these many "mad dances" made the Netherlands rich. At the beginning of the 19th century, the Netherlands only planted 130 acres of tulips. By the middle of the 20th century, it had developed to more than 20,000 acres, accounting for more than 80% of the world's total tulip exports, and was sold in 125 countries, and was hailed as the "world's queen of flowers." The emergence of this super-powerful product made tulips worthy of being the national flower, and worthy of being designated as one of the "four national treasures" along with windmills, cheese, and wooden shoes. Another theory is that during the Second World War, there was a famine in the Netherlands in the winter of one year, and many starving people ate the bulbous rhizomes of tulips and relied on tulips to survive. The Dutch were grateful for the life-saving grace of tulips, so they made tulips their national flower. In addition, tulips are also the national flowers of Turkey, Hungary and Iran. 5. The "Gerci" type tulips made their debut in Beijing. At present, the green leaves with black spots and the magenta, orange and white-edged tulips in Beijing Zhongshan Park have attracted many tourists. These 20 varieties of "Gerci" type tulips introduced from the Netherlands are making their first appearance in Beijing. The 10th large-scale tulip flower exhibition in Zhongshan Park, with the theme of "Return to Nature", kicked off on April 21, and more than 60 varieties and 300,000 tulips will be exhibited one after another. According to park engineer Meng Lingyang, in addition to some conventional varieties such as 'Orange Bouquet', 'Happy Time' and 'Grace', 20 new varieties of tulips of the 'Grich' type, including 'Dream Ship', 'Marian' and 'Yellow Dawn', were added to the flower show this year. This type of tulip is characterized by early flowering, large flower shape and short plant shape. These tulips have different flowering periods, and the latest blooms in early May. The layout of tulips in the park is divided into regular and natural styles. Regular layouts are generally arranged in a matrix. The natural layout combines the terrain of the park, gives full play to creativity, and randomly arranges them to achieve a landscape effect that is harmonious with the environment. The picture shows the blooming 'Grich' type tulips in Beijing Zhongshan Park, attracting the attention of tourists.