Chinese Name: Pinctada: Fauna: Mollusca: Claphabranchia: Heteropetala: Pinctada Distribution: China, Guangdong and Hainan. Morphological characteristics, living habits, basic classification, species distribution, historical discovery, pearl culture, pearl inserting culture, social benefits and morphological characteristics pearls are the products of shellfish. Many kinds of shellfish, such as abalone, mussels, mussels and oysters, can produce pearls. But the most common, high yield and good quality is marine pearl oyster. Pinctada is also a bivalve, which is the same as mussels and scallops that we will talk about later. It is a species that lives on rocks, coral reefs, gravel or other shells with enough silk. Pinctada is a kind of warm seafood, which is very common in Fujian and Guangdong coastal areas, especially in Guangdong coastal areas. Pinctada is also a kind of bivalve, like mussels and scallops, living on rocks, coral reefs, gravel or other shells with plenty of silk. Pinctada is a kind of warm seafood, which is very common in Fujian, especially in the coastal areas of Guangdong. There are many kinds of Pinctada, such as Pinctada maxima, Pinctada martensii, Pinctada penguin and so on. Among them, Pinctada martensii is the most common pearl, from which Hepu's pearls are collected. Living habits: the sea is clear and the water is not urgent. It lives in muddy sediments mixed with gravel in the intertidal zone to 10 meters deep. The seawater temperature required for its normal life is between 15-25 degrees Celsius. When the water temperature is above 30 degrees Celsius or below 13 degrees Celsius, it loses its normal activity ability. Shells with thick nacre are excellent varieties of cultured pearls in seawater, which can produce large-scale high-quality pearls. Hepu, Guangxi has been famous for its high-quality pearls produced by Pinctada since ancient times. South China Sea Fisheries Research Institute has cultivated large pearls which are rare in the world by using Pinctada maxima. The culture of pearl oyster is suitable for the quiet inner bay of Apollo, the seabed with more sand, mud, stones and gravel, and the place with less intense water flow. The spawning period is from May to September. It takes 18 ~ 20 days to develop into a larva under the suitable conditions of salinity of 27 ~ 3 1 ‰ and water temperature of 26 ~ 29℃. The bait can be flat algae and diatoms. Pearl oyster has strong adaptability to high salinity environment, but poor adaptability to low salinity environment. The meat of pearl oyster is edible, and its shell can be used as raw material for shell carving, mother-of-pearl and buttons. There are many kinds of pearl oyster, such as pearl oyster, pearl oyster, pearl oyster, penguin pearl oyster and so on. At present, there are mainly three kinds of pearls used for breeding: (1) Pinctada maxima, also called white butterfly, which can cultivate white and golden pearls. Nanyang pearl is cultivated with this kind of pearl shell. (2) Pinctada, also known as black butterfly, is used to breed black pearls. Black pearls in Tahiti are cultivated with mother-of-pearl. (3) Pinctada martensii is used for cultivating common seawater pearls. "Hepu Pearl" and "Nanzhu" are cultured with this shellfish. Pinctada penguin is a newly cultivated pearl culture variety in recent years, which is mainly used to cultivate enclosed pearls. Species distribution Hepu shellfish is the main pearl species in Japan at present. Hepu shellfish are distributed in the coastal areas of Guangdong, Guangxi and Taiwan Province Province, from the south of Chiba Prefecture to the Philippines, Vietnam, Myanmar, Indonesia, Sri Lanka and Australia. Pearl oyster is your kindness. It is a new kind of oyster bred by crossing Hepu shellfish with black butterfly shellfish by taking advantage of its rapid growth and excellent color. Xie Shi Pinctada is mostly used to produce medicinal pearls, and cultured pearls are mostly yellow series. The butterfly queen is a kind of big conch, which is rich in the Caribbean of Central America. The real pearl produced is called Kangkezhu. Kingdee turned into a golden yellow pearl. Pinctada maxima, also known as Pinctada maxima, produces large pearl particles and is called Nanyang Pearl, which is mostly produced in the southern Philippines, such as Hainan Island, Leizhou Peninsula to the west coast of Australia, Solomon Islands, Malay Islands and other places. Black butterflies produce black pearls. Pinctada penguin Pinctada penguin's shell is an oblique square, its front ear and back ear extend in a handle shape, the front is short and the back is long, the two shells are prominent, and the shell surface is black and covered with fine hairs, so it is named after the Antarctic penguin. Semi-circular pearls can be cultivated and distributed in southern Kyushu, Ryukyu Islands, Penghu, Philippines and mainland coastal areas. Butterflies are land lakes, and real pearls growing in rivers are seedless real pearls. History has found that pearl shells have a long history as ornaments. Ancient Egyptians, Persians and Indians used pearls and shells to make beautiful decorations and decorations on utensils. The earliest use of pearl shells as decoration in China began in the Warring States Period. The colors of mother-of-pearl are white, pink, milky white, milky yellow, bluish white, yellow and bronze. There are bright pearls in the shell, which are more colorful and beautiful under the light. The main components of shells are aragonite, calcite, organic matter and water, and the hardness is 2.5-4 degrees Mohs. Usually, shells have better toughness. Generally opaque. Pearl shell is a natural work of art, and it is also a material for making advanced handicrafts, and it is a rare collection. Distributed in the waters near Guangdong and Hainan in China. Shells with thick nacre are excellent varieties of cultured pearls in seawater, which can produce large-scale high-quality pearls. Hepu, Guangxi has been famous for its high-quality pearls produced by Pinctada since ancient times. South China Sea Fisheries Research Institute has cultivated large pearls which are rare in the world by using Pinctada maxima. Up to now, the largest pearl shell 1995 in China has been found in Hepu County, Guangxi, weighing 28.3 kg. According to relevant experts' research, this shell was produced in the late Tang Dynasty. Today's shells are as hard as steel and make a golden bell-like sound when struck. Shells are sparkling, bejeweled and brightly colored. Now, the largest pearl shell in China, as an important cultural relic specimen, is collected in Hepu County Museum. Molluscs, Claudiobranchia, Heteropoda, Pinctada. The two shells are unequal, the left shell is slightly convex, and the right shell is flat, usually with a foot opening. There are ears at the top of the shell, the rear ear is larger than the front ear, and the surface of the shell often has scales. There is no water pipe, and the feet are tongue-shaped. Living in tropical and subtropical oceans, living with their feet on shallow sea rocks and coral reefs below the low tide line. The culture of pearl oyster is suitable for the quiet inner bay of Apollo, the seabed with more sand, mud, stones and gravel, and the place with less intense water flow. The spawning period is from May to September. It takes 18 ~ 20 days to develop into a larva under the suitable conditions of salinity of 27 ~ 3 1 ‰ and water temperature of 26 ~ 29℃. The bait can be flat algae and diatoms. Pearl oyster has strong adaptability to high salinity environment, but poor adaptability to low salinity environment. The meat of pearl oyster is edible, and its shell can be used as raw material for shell carving, mother-of-pearl and buttons. The dazzling pearls in pearl oyster culture come from mussels and seashells, and the pearls in the sea are very similar to mussels. They all have two hard shells, and the opening and closing of the shells are completed by muscle columns. When the shell is opened, sand or bugs will fall in. When the pearl oyster is stimulated by foreign objects, it will secrete nacre and surround the invaders. Over time, a pearl was formed in the pearl shell. This is the formation process of natural pearls. However, due to the scarcity and quality control of natural pearls, people began to cultivate pearls artificially. Pearls like to inhabit the shallow sand bottom with quiet water, smooth temperature and rich bait, and the salinity of seawater should be appropriate. Every April and May, Pinctada larvae begin to multiply in large numbers. People use artificial reefs to attach the larvae of pearl oyster to them. When the seedlings grow up, the pearl oyster is taken out for artificial nuclear transplantation. The pearl core is made of plastic and stone. A few months later, pearls began to form by implanting the nucleus into the pearl shell and then putting the pearl shell into the sea. Of course, it takes one to several years to harvest pearls. Introduction to pearl cultivation by inserting nucleus is the central link and key technology of pearl cultivation. Its meaning is to operate on the mother pearl, insert the nucleus into the mother pearl and transport a small piece of mantle tissue, and then carefully cultivate the inserted nucleus of the operated shellfish to promote or accelerate the formation of pearls. The inventive principle of this technology is mainly based on the causes of natural pearls, that is, under abnormal circumstances, such as sand and parasites invade and stimulate the mantle of mother-of-pearl, or due to pathological influence, some epidermis is trapped in connective tissue, resulting in abnormal proliferation, leading to the formation of pearl sacs, and mother-of-pearl secretes to form natural pearls. From the technical principle of the invention, it is not complicated, but the technical operation is very difficult. On the other hand, as far as the technology itself is concerned, it has no good effect under any conditions or in any kind of mother-of-pearl surgery. In addition, different mother-of-pearl inserts have different reactions. Therefore, it is unrealistic to hope that a set of ready-made nuclear insertion technology can be applied to all nacres. The nuclear insertion of Pinctada maxima is an obvious verification. Japan adopted the nuclear insertion method of Pinctada maxima in Hepu, and studied it for 10 years after the nuclear insertion failed, only then did it overcome the technical difficulties and create a new nuclear insertion technology of Pinctada maxima. So is China. The South China Sea Fisheries Research Institute and other units have also intermittently experienced setbacks and failures in the research on pearl cultivation of Pinctada maxima. It took 10 years to master the internal physiological laws of Pinctada maxima, create new methods of special operation and treatment, cultivate large-scale commercial pearls in China for the first time, and fill the gap in pearl culture in China. It should be said that the nuclear insertion technology of Pinctada maxima is relatively advanced in the current pearl culture technology. But for commercial reasons, all countries keep this secret. Therefore, taking Pinctada Hepu as an example, this paper introduces the method of cultivating pearls by inserting nuclei. The first function of pretreatment is to promote ovulation or weaken gonadal development of attached mother shellfish; The second is to appropriately inhibit its activity and reduce its physiological function, so that it is in a state suitable for nuclear insertion. The specific methods are: 1. Suppress spawning. After the sperm eggs are naturally discharged, the selected healthy mother shellfish will be raised in cages in time and moved to the seabed with low water temperature to inhibit the vitality of the mother shellfish and prevent the gonads from developing and maturing again. 2. Before nuclear implantation, if the gonads of mother shellfish begin to mature, the following methods can be adopted: first, increase the water temperature to accelerate or promote the maturation of sperm eggs; The second is to induce labor. After spawning, the density of mother shellfish should be appropriately increased and hung in deep water for later use. 3. Clean the pretreated mother shellfish, then hang them in a shellfish cage so that their ventral surfaces are close to each other, or put them into sea water for treatment. After a period of time, when they naturally open their shells due to lack of oxygen, wooden wedges can be inserted into the two shells to expose the soft parts to prepare for the next nuclear insertion. Cell slices are made from the mantle tissue of Pinctada, which is the material basis for the formation of nacre and the secretion of mother-of-pearl, so we should be especially careful when making them. Small cell shell refers to the shell used to make small cell pieces, and generally the same kind of shell is selected. The making method of the small piece is to take out the free mantle part on the small piece of shell with scissors, wash it with clean seawater, trim it, cut off the edge part, and then cut it into square pieces with the size of 1/3 of the bead center diameter. Cut into small squares, disinfect and dye with 2% mercuric chloride, and then soak in clean seawater for use. There are three methods for inserting the nucleus of Pinctada fuciformis: surface patch method, rolling pushing method and first sending method. Before inserting the nucleus, put the mother shell on the nucleus inserting table with the right shell facing up and the left shell facing down, poke the gill leaf at the right nucleus of the mother shell with a flat needle to expose the soft part, wipe off the sludge and mucus near the soft part and the shell mouth with cotton, and then make an incision at the black-and-white junction of the foot base with a cutting knife, which is just big enough to feed the pearl core and deep enough to cut the epidermis. Then insert the needle into the incision, dial the nuclear delivery channel in the direction of "left pocket" and "right pocket" respectively, then hook or press the foot of the surgical shell with a crochet needle or a flat needle of 1 in the left hand, and send the large nucleus and nucleus pulposus into the "left pocket" and "right pocket" respectively with the nuclear delivery device in the right hand. Immediately after the right core of the shell is inserted, the operating shell is turned upside down, that is, the right shell of the mother shell is downward and the left shell is upward. An incision is made at the black-and-white junction of the base of the left foot of the shell, and the channel needle is used to dial the core conveying channel from the incision to the "lower foot", then the right hand holds the needle to press the foot of the operating shell, and the left hand grasps the core feeder to send the small core to the "lower foot" position. Immediately after each nuclear site is delivered, small cell pieces are delivered to the nuclear surface with a delivery needle. When sticking the patch, the skin of the small piece must be close to the nuclear surface. After the operation, take out the cork, and the oyster shell can be temporarily kept in the basin. This is the method of inserting the core first, and then sending the curved surface to insert the core. The key point of the core winding and pushing method is to send the core to the middle of the channel, then stick a small piece on the surface of the core, and then slowly roll the push chip with the channel needle to the conveying position. The nuclear insertion method is simple to operate. After the incision and channel are formed, the chip should be sent to the "site" with a needle, but care must be taken that the skin of the chip should face the direction of the channel opening at the delivery site. Then the core is sent to the site by the core feeder to press the small pieces of skin. After the operation, take out the cork and temporarily keep the shellfish in a basin. The above three methods have different effects. The former pearls have the best quality, and the round ones account for a large proportion. The pearl quality of the latter two is poor, and there are more dirty beads and tail beads. Rehabilitation after surgery, from a medical point of view, is to rest for a period of time in a special environment to achieve the purpose of rehabilitation. The mother shell after operation is very weak due to trauma and fatigue, so it is necessary to take self-cultivation measures after operation. The core insertion technology of Pinctada is mainly to implant the pearl core into the mother body to cultivate pearls. In this sense, the recuperation after Shubei operation is not only to eliminate fatigue and restore health, but also to continue to reduce its vitality, prevent erosion and improve the rate of pearl formation. Therefore, in order to achieve the purpose of recuperation, we should not only choose excellent places, but also adopt various methods of recuperation, such as loading and unloading and stocking with bamboo cages or plastic wire cloth cages, and plastic wire cages with sparse or dense meshes. Specifically, in the rest area, the water depth is suitable, and the water flow is not smooth, so shellfish can be stocked in a cage with sparse mesh rubber wire cloth, with 30-40 shellfish per cage. If the water exchange in the rest area is fast and the tide is stable, dense bamboo cages can be used for rest, and the stocking density can be changed according to the situation. By doing so, on the one hand, Shubei can practice quietly, on the other hand, his vitality can be properly controlled, so as to improve the rate of nucleus retention and survival rate. The length of the rest period mainly depends on the recovery of Bessie's mother after operation and the situation of the upper layer of the pearl, which is generally 20-30 days. After the dormancy period of pearl culture, that is, when the oyster body recovers, the nucleus is stable and pearls begin to form, the cage can be changed from the dormancy period to the general oyster cage, and the stocking density can be reduced, and then it can be moved to the pearl culture fishery for culture and pearl culture. During the pearl culture period, the culture method of operational shellfish is basically the same as that of general adult shellfish. Only the choice of pearl culture fishery is emphasized here. The ideal environmental conditions of the fishing ground are that the water depth is more than 5 meters, the tidal current is smooth, the water temperature is below 30℃ in summer and 15℃ in winter, and the water quality is not polluted. It is best to inject or flow a small amount of fresh water into the fishing ground. Because such a fishing ground is rich in water quality, rich in bait organisms, pearls form quickly and have good quality, and are generally white. The length of the pearl culture period mainly depends on the specifications of the inserted pearl core, the thickness requirements of the pearl layer, the environmental conditions of the pearl farm and the pearl culture method. In China, if pearls are cultured with small pearl cores, the pearl culture cycle is 7 months to 9 months; With nucellar nucleus, the breeding period of pearls is 1 year-1.5 years; For megakaryoids, the incubation period is longer, 1.5 -2 years. After the expiration of pearl culture, and the thickness of pearl layer meets the requirements of commodity specifications, it can be harvested. The main method of harvesting is to kill shellfish and take pearls out of pearl bags. The harvesting period is usually in winter. Due to the low water temperature during this period, the speed of pearl secretion by mother-of-pearl is slow, and the surface of pearl secreted is delicate, smooth and shiny. Pinctada maxima, also known as Pinctada maxima, is a precious pearl shellfish unique to the South China Sea. It is shaped like a plate, and it is very big. It is generally 24 cm long and weighs 6-7 kg. The largest is more than 32 cm long and weighs 10 kg. It is the largest variety of pearl oyster. There are Pinctada martensii, Pinctada penguin, Pinctada maxima and Pinctada maxima in Hainan, and the reserves of Pinctada maxima account for about 90% of the total reserves of all kinds of Pinctada maxima in Hainan. Pinctada maxima has high economic value. Its shell is made of drugs and process raw materials, and it is widely sold in the international market at a price of 8-9 yuan RMB per catty. Its meat quality is delicious and its nutritional value is high. What's more valuable is that the pearls cultivated by Pinctada maxima have large particles, good color and high price. Pearl has always been a valuable ornament and a valuable medicinal material. It has been listed as an important medicinal material in the medical book Bielu of famous doctors in the Three Kingdoms period. At that time, there were pearls in the prestigious "Zhuge Xing Junsan". According to Li Shizhen's Compendium of Materia Medica, pearl can "cure the cloud of eyes and skin" and pearl powder "makes people moist and look good". In medicine, it has the effects of calming nerves, clearing away heat and toxic materials, diminishing inflammation and relieving pain, moistening skin, closing mouth and promoting granulation. There are more than 20 kinds of prescriptions in China, and pearls are the main drugs. Dozens of Chinese medicines, such as Liushen Pill, Anguan Niuhuang Pill, Xingjun Powder and Babao Eye Drops, all contain pearl powder. Nowadays, people also use pearl powder and skin care materials to make high-grade cosmetics such as pearl cream, pearl dew and pearl cream, which are deeply loved by people. After liberation, the pearl breeding industry in Hainan Province has developed greatly, and pearl farms have been established to cultivate pearls artificially. Artificial pearl breeding is to put the pregnant mother Pinctada after operation into a special delivery room made of nylon net. A mother pearl lives in the delivery room and is put back into the sea area with gentle water flow and rich bait to "give birth" to their "jiaozi". This process is called pearl cultivation period and needs careful management for one or even two years. Pinctada is a small creature with almost no self-defense ability. The fierce octopus and crab in the sea are the enemies of Pinctada. They will wait for an opportunity to break into the "delivery room", bite off the shell and eat their meat. Small shellfish such as oysters and barnacles in the sea also love to nest on mother-of-pearl, which seriously affects the normal growth of mother-of-pearl. In this way, pearl farming should not only guard against enemy invasion every morning and evening, but also regularly remove "hidden dangers" on pearl shells. In case of typhoon and rainstorm, you should go out to sea immediately and move mother-of-pearl to the bay. Of course, pearls are the crystallization of mother-of-pearl's life, and the crystallization of pearl farmers' sweat and painstaking efforts. Social welfare is stepping on the pearl shell, floating out of the blue sea in the first ray of sunshine in the morning, hovering in the sky and singing. Pearl-like soft light shines on her lips, giving the pearl shell a pure and noble meaning. Deep-sea pearl oyster has the color of pearl and glows in the sun. A pearl will gradually form where the pearl shell has been injured, and people, like the pearl shell, will turn the wound of life into a beautiful pearl to meet the sunshine after the storm. There are many kinds of shellfish that can produce pearls in the world. The shell surface and shape of pearl oyster are very different. Therefore, it is difficult to specify which shellfish is pearl oyster or not. The radiation pearl oyster is oval or disc-shaped, and the left shell is slightly larger than the right shell. There are ribs on the shell surface, and there are scales near the edge on the ribs. The hinge is long, with small teeth at both ends, and a large closed shell muscle mark in the center of the two shells. The surface of the shell is generally light brown or gray, with dense reddish-brown radiation lines; It has a mother-of-pearl luster. Pearl oyster belongs to bivalve mollusk. It is named because it can produce pearls. China is the first country in the world to understand and use pearls. As early as the12nd century, the people of China planted small ivory or woodcarving Buddha statues in pearl shells and took them out a few years later. The Buddha statue is covered with a layer of pearls, which is crystal clear and beautiful. This is the famous colorful bead Buddha. People in China not only regard pearls as treasures, but also use them as medicines. China is one of the earliest countries producing pearls in the world. Nanzhu in Beibu Gulf has always been a famous hometown of pearls. In recent years, with the continuous improvement of artificial pearl culture technology, the output of pearls has soared. The jewelry made of pearls and shells with beautiful luster is also deeply loved by people.