Why is kidney bean called kidney bean? I am stumped!

Kidney bean, whose scientific name is kidney bean, belongs to leguminous kidney bean. Kidney bean originated from Mexico and Argentina in America, and was introduced and cultivated in China at the end of 16. Kidney beans are rich in nutrition. According to the determination, every100g of kidney bean contains 23.1.3g of protein, 56.9g of carbohydrate and 76mg of calcium, which are rich in B vitamins, and fresh beans are also rich in vitamin C. From the nutritional point of view, the content of protein is higher than that of chicken, and the content of calcium is 7% of that of chicken. Vitamin B is also higher than chicken. Kidney beans can be used as raw materials for developing new varieties of nutritious staple food of grain beans. Kidney bean granules are full and fat, and can be cooked and stewed. Kidney beans also have high medicinal value. According to the records of ancient Chinese medical books, kidney bean is sweet in taste and warm in nature, and has the effects of warming the middle warmer, reducing qi, benefiting the stomach, stopping hiccups, tonifying kidney and benefiting qi. It is a good product for nourishing and dietotherapy. Kidney bean is also a rare food with high potassium, high magnesium and low sodium. Every100g contains 65,438+0,520mg of potassium, 65,438+0,93.5mg of magnesium and only 0.8-0.9mg of sodium, which is of great use in nutritional therapy. Kidney beans are especially suitable for patients with heart disease, arteriosclerosis, hyperlipidemia, hypokalemia and salt aversion. According to modern medical analysis, kidney bean also contains saponins, urease, various globulins and other unique components, which can improve human blood immunity, enhance disease resistance, activate lymphocyte T cells, promote DNA synthesis, and inhibit the development of tumor cells, so it has attracted the attention of the medical community. The urease content in it has a good effect on patients with hepatic coma. Kidney bean is a nutritious food, but its seeds contain a poisonous protein, which can only be destroyed at high temperature. Therefore, eating kidney beans must be cooked, eliminating unfavorable factors, seeking advantages and avoiding disadvantages, and giving full play to its nutritional value. Kidney beans have developed roots. The stem is trailing, semi-trailing or short. Primary true leaves are solitary and opposite; The true leaves of the future are trifoliate compound leaves, nearly heart-shaped. Racemes are axillary and butterfly-shaped. Corolla is white, yellow, lavender or purple. Self-pollination, a few can cross-pollinate. Each inflorescence has several flowers to more than 10, and generally bears 2 ~ 6 pods. Pod length 10 ~ 20 cm, straight or slightly curved, round or oblate in cross section, densely villous epidermis; Young pods have stripes of green, yellow, purple or different shades (magic beans are sold in supermarkets, and the skins are purple and dark red, etc. ), and it is yellow-white to yellow-brown when mature. With the development of pods, the vascular bundles at the back and ventral suture gradually developed, and the layers of thick-walled tissue in mesocarp and endocarp gradually increased, which reduced the quality of fresh food. Therefore, the harvest of tender pods should be timely. Each pod contains 4 ~ 8 seeds, kidney-shaped, with red, white, yellow, black and striped colors; 1000-grain weight is 0.3 ~ 0.7 kg. Chromosome number 2n=22. Kidney bean can be divided into three types according to the growth habit of stem: the stem of creeping kidney bean grows by left-handed winding, the terminal bud is leaf bud, and each leaf axil can form a lateral vine or inflorescence; The growth period is generally 100 ~ 120 days; There are many inflorescences, long flowering and pod setting time and high yield. Its dwarf variety (dwarf variety) grows for 4 ~ 8 days, the terminal bud is formed, and the inflorescence is no longer elongated. The lateral branches or inflorescences occur in the axils of each node, and the terminal buds also form inflorescences after the lateral branches grow for several days; The growth period is generally 50 ~ 60 days; Fewer inflorescences, fewer flowers and pods, and low yield. The harvesting period is concentrated, which is suitable for mechanized cultivation. The intermediate type between creeping species and dwarf species is semi-creeping species. In addition, according to the pod structure, it can be divided into hard pod kidney bean (the inner pericarp of the pod is leathery) and soft pod kidney bean (the pod is full and tender with little fiber). According to the purpose, it is divided into pod species and grain species. Bean is a warm-loving plant. The suitable temperature for growth is 15 ~ 25℃, and the suitable temperature for flowering and pod setting is 20 ~ 25℃. Low temperature below 10℃ or high temperature above 30℃ will affect the growth and normal pollination and pod setting. It is a short-day plant, but most varieties are not strict about the length of sunshine, and the cultivation season is mainly restricted by temperature. Cultivation in spring and summer in northwest and northeast China; Spring sowing and autumn sowing are carried out in North China, Yangtze River Basin and South China. Direct seeding or seedling transplanting can be used. The requirements for soil are not strict, and loam or sandy loam with pH of 5.5 ~ 7 is suitable. Soil with good drainage, loose soil and rich organic matter is beneficial to root growth and nodule formation. It is advisable to avoid continuous cropping and implement 2 ~ 3 years' rotation. It needs plenty of light, and it is easy to drop flowers and pods when the light is weak. Most vine varieties are cultivated in scaffolding, and the row spacing between plants is wider, generally about 7000 plants are planted per mu; The row spacing of dwarf plants can be smaller, generally about 15000 plants per mu. In order to keep the stem and leaf growing well and improve the pod setting rate, in addition to applying organic fertilizer as base fertilizer, more topdressing should be applied after flowering. Generally, young pods can be harvested about 10 day after flowering. The main diseases are Fusarium wilt, rust and anthracnose. The main pests are stem borers, bean stalk flies and so on. The young pods contain about 6% protein, 0/0% fiber/kloc and 0/~ 3% sugar. Dried beans contain about 22.5% protein and 59.6% starch. Fresh pods can be used as vegetables, dehydrated or canned. As for kidney beans, why are they called kidney beans? Just like your name. Why do you call it that? You can call it Zhang San, Li Si, Wang Lao Wu, or you can call it 1, 2, 3, 4, 5, 6, 7, or even A, B, C, D, E, F, G, whatever you want. It's just a code name. This is just a habit. That's all.