白菜（Pak-choi; Chinese cabbage）

cruciferae is a variant of the cabbage subsethic, a year or two of herbs made from green leaves. The name Brassica campestris L. ssp. chinensis (L.) Makino. Var. Communis Tsen et Lee, alias common cabbage, cabbage, green vegetables, rape, etc. Cabbage evolved from B.campestris L. Chromosome number 2n-2x-20. Every 100g fresh vegetables contains 93-95g of water, carbon water
compounds
2.3-3.2g,
protein
1.4-2.5g,
vitamins
C30-40mg, cellulose 0.6-1.4g, and other vitamins and minerals. Stir-fry, make soup, marinade. It is widely cultivated all over China. South of the Yangtze River as the main production area, planting area accounted for autumn, winter, spring vegetable planting area of 40-60%. After the 1970s, the cultivation area in northern China also expanded rapidly.botany: shallow root, must be developed root, strong regeneration force, suitable for seedling transfer. Stems are short-shrinking stems in nutritional growth and elongate at high temperatures or when planted too tightly. The short stem has the raw lotus leaf on it, which is the main edible part and the assailation organ. Leaf circle, egg circle, inverted egg circle or oval shape, full edge, wave or jagged, light green, green or dark green; Flower stem leaves are generally handleless, holding stems or half holding stems. Complex flower sequence, full flower, crown yellow, petals 4, cross-shaped arrangement; Alien pollination, insect-borne flowers. Long-horned fruit, which contains 10-20 seeds, mature horned fruit is easy to crack and needs to be harvested in time. Seeds are nearly round, red-brown or tawny, with a thousand grains weighing 1.5-2.2 grams.types and varieties: according to morphological characteristics, biological characteristics and cultivation characteristics, cabbage can be divided into autumn and winter cabbage, spring cabbage and summer cabbage, including different types of varieties. (1) Autumn and winter cabbage: widely cultivated in southern China, many varieties. The plant type is upright or waist-to-waist, mainly cultivated in autumn and winter, according to the color of the leaf handle is divided into white terrier type and green terrier type. The representative varieties of white terrier type are Nanjing short-footed yellow, Chang-governor white-footed, Guangdong short-footed wuye, Hefei small leaf vegetables and so on. The representative varieties of the type of green terrier are Shanghai dwarf, Hangzhou early oil winter, Changzhou green terrier and so on. (2) Spring cabbage: plants more carried, a few erect or micro-beam waist. Strong winter, cold, abundant. According to the pumping morning and evening and the supply period is divided into early spring dishes and late spring dishes. The representative varieties of early spring vegetables are The bright white leaves of Nanjing, the white of Wuxi March and the late oil winter of Hangzhou of the Green Terrier, and the slow March of Shanghai. The representative varieties of late spring vegetables are The White Terrier's Nanjing April White, Hangzhou Silkworm Cabbage, and the Green Terrier's Shanghai April Slow and May Slow. (3) Summer cabbage, summer and autumn high-temperature season cultivation, also known as "fire cabbage", "fu vegetables", representing varieties of Shanghai fire cabbage, Guangzhou horse cabbage, Nanjing dwarf one and so on.growth and product formation: cabbage reproductive cycle divided into nutritional growth and reproductive long-term. Take autumn and winter cabbage as an example, nutrition and long-term include: (1) germination period: from seed germination to seed leaf development, real leaf revealed. (2) Seedling period: from the real leaf revealed to the formation of a leaf sequence. (3) Lotus period: plants exhibit 1-2 leaf sequence, is the main period of individual production formation. Reproductive life includes: (1) pumping pregnancy bud period: pumping flowers, issuing flower branches. Stem leaves grow on the main stems and side branches, and buds form at the top. (2) Flowering results period: buds grow up, flowering, strong.cabbage with lotus leaves as the product. Autumn cabbage generally 1.5-2 days differentiate a new leaf. Such as Hangzhou oil winter and other varieties of single plants, generally with 25-30 leaves, which mainly consists of the 9th-24 pieces of lotus leaf production. The growth rate of leaf area in seedling period is faster than that of leaf weight, while the growth rate of leaf weight in lotus stage is faster. By the later stage of growth, the growth of leaf weight is mainly the growth of leaf shank, which often accounts for 75-80% of the total leaf weight, and is the storage organ of nutrients. The yield per unit area is composed of the number of plants and the weight of a single plant, while the weight of a single plant is restricted by two factors: the number of leaves and the weight of the leaves. Most varieties are leaf heavy, leaf weight increase mainly depends on leaf area increase and leaf handle weight gain.cabbages enjoy a cool climate, with average temperatures of 18-20 degrees Celsius and sunny conditions. -2 to -3 degrees C can safely winter. High temperature growth and weakness above 25 degrees C, susceptible to viral diseases, only a few more heat-resistant varieties can be cultivated in summer. The seeds and green plants of cabbage germination are below 15 degrees C in temperature, and after a certain number of days to complete springing, the seedlings begin to differentiate the buds, while the leaf differentiation stops. Pumping and flowering under long sun and high temperature conditions. However, there are obvious differences in the requirements of different varieties for long sun.cultivation techniques: cabbage type, variety, adaptability, in China's Jiangjiang and Huai regions, in addition to winter and early spring line simple cover cultivation, can be cultivated in many dewy areas; In cultivation generally according to three seasons arrangements: (1) autumn, winter cabbage: seedling transplanted, harvest-based plants. South China is September-December seeding, the harvest in stages to February of the following year, Jiang, Huai area is from early August to mid-October to sow seeds, frozen before the harvest is completed. (2) Spring cabbage: late autumn sowing, small seedlings winter, the next spring harvest into plants; Early spring with cold beds to sow seedlings or after the spring after planting seedlings, can also be harvested and planted. (3) Summer cabbage: to cultivate and harvest vegetables mainly, early May to early August can be sown at any time, and constantly harvest. Cabbage is often rotated with melons, beans and field crops. Spring cabbage and eggplant, melon, beans, potato taro vegetables for seeding, summer cabbage and celery,artemisinin, carrots and other vegetables mixed, autumn and winter cabbage can be made with ball kale, broccoli, shoots, potatoes and other inter-species. The annual supply can be achieved by using different varieties to seed.cabbage in addition to early spring, summer and so on for the cultivation of vegetables and the use of live broadcast, the general line of seedling transplant. It is advisable to choose water-protected fertilizer, well-drained soil for seedling, before harvesting to early tillage and sunbathing Sowing should be well-homogened and appropriately sparsely sown. After the seedling and time seedlings, to avoid the growth of the seedlings, after the fertilization and watering, and pay attention to the seedling weeding and pest control. Generally transplanted 25 to 30 days after broadcasting. Planting fields in advance fertilization, tilling and , farming. Planting density varies according to variety, season and cultivation purpose, and most varieties are 20-25cm long. Planting depth varies according to climate, soil quality, early autumn should be shallow planting, to prevent deep planting rotten heart; The soil is loose, the planting can be slightly deeper, and the sticky soil should be shallow.cabbage root group shallow, weak absorption capacity, during growth should continue to supply fertilizer water. The pursuit of quick-acting nitrogen fertilizer many times is an important measure to promote the growth of cabbage and ensure its abundance. The principle of rational fertilization: First, to set the planting in time to catch fertilizer, promote the growth of seedlings, and second, to grow with the cabbage individual, increase the concentration and dosage of fertilizer. As for fertilization methods, periods, dosing, depending on the weather, seedlings, soil, etc. Watering is carried out in combination with fertilizer recovery. Water is essential for 3 to 5 days after planting, especially in summer and early autumn, and must be watered every morning and evening for 3 to 4 consecutive days after planting. Cultivated cabbage should be applied more
organic
fertilizer as a base fertilizer, during the growth of appropriate fertilizer, can also be combined with spray irrigation for leaf fertilizer.cabbage plants grow to a certain size and can be harvested at any time. Harvesting standards: the outer leaf color began to fade, the outer leaves of the base yellow, leaves from vigorous growth to closed growth, the heart leaves elongate to the outer leaves flat (commonly known as "flat mouth"). After planting autumn cabbage in Jiang and Huai areas, 30 to 40 days can be harvested one after another, and it takes 50 to 60 days to harvest the plants; It only takes 40 to 60 days to sow and harvest in southern China.the field should be strictly isolated from other vegetables and other varieties of cabbage, as well as from other cultivated crops with chromosomal base x 10 in the genus. The space isolation distance of the original plant field is at least 2000m, and the isolation distance of the production field shall not be less than 1000m. The main seeding methods are: (1) plant adoption method: autumn appropriate planting. Before harvesting, select the excellent plants with strong growth and characteristics of this variety as planting plants, and plant according to the line distance of about 45cm. Jiang, Huai area should pay attention to take appropriate coverage of cold-proof, weak cold-resistant long terrier cabbage, can cut off the upper part of the leaves, leaving only the leaf handle and heart leaves planted, and then appropriately covered with grass. The following spring to remove the cold cover, in the middle of farming, weeding, fertilization, flowers pay attention to the prevention and control of aphids, etc. , Jiang, Huai area generally from May to June to harvest seeds. (2) Semi-plant seeding method: Jiang, Huai area more than in early and mid-October sowing seedlings, pre-winter planting. The following spring, the strong were chosen to pick the species. The seed yield is higher and the cost is lower, but the quality is not as good as that of the plant. (3) Small plant seeding method: Jiang, Huai area in early February sowing, after seeding to go to miscellaneous once or twice, according to the seedling distance of about 20cm to retain seedlings, late May to early June harvest seeds. Spring cabbage left more combined with spring field production, to poor retention.Storage processing: (1) pickled cabbage: harvest fully mature plants, remove the roots and old leaves, wash, when the water evaporates and wilts slightly, add salt and dry kneading, code into a pottery bowl or large wooden barrel. One layer of vegetables, one layer of salt, until the code is full, press heavy stone. After a few days to let the juice leach, and then flip up and down again, such as the front pressure after about 25-30 days, can be eaten. Add 2.5-4kg of salt to every 50kg fresh dish. (2) Cabbage dry: harvest fully growing plants, root and old leaves, wash, boiling blisters after a moment on the shelf drying.pest control and control: common diseases are viral diseases, frost mold disease, white spot disease, root swelling disease and so on. The main pests are vegetables, vegetables, wild grasshoppers, vegetables, kale nightingach, yellow bar jump armor, vegetable powder butterfly and so on.。