China. Water chestnut I. Cultivation history and the current situation of water chestnut, the ancient name of peony, eider gromwell, also known as wu yao, the south called horseshoe, ground chestnut. Scientific name (Heleahat is tube ro sa ashulus) ancient times it is listed as aquatic fruits, Ming ancient book Wang Xiang Jin "Qunfang Spectrum" and the water chestnut, rhombus, lotus, gravy with melon class, classified as ze food class, melon fruit class. Water chestnut has a long history in Shaoxing, according to the book of the Han Dynasty: "Wang Mang end, the south of the famine, the people into the wild swamps, digging shells Common Gromwell and food". And the south to Jiang, Zhejiang mainly, and Zhejiang especially to Shaoxing, Shengxian, Zhuji and other places for the main place of origin, can be seen 2000 years ago, Shaoxing has been widely cultivated. Shaoxing history of water chestnut cultivation is widely distributed, according to the post-liberation statistics, especially in Jianhu, Anchang, Tao Yan, Lizhu for more than an area of more than 5,000 acres, the acquisition in the sixties is also as high as more than one hundred and thirty thousand quintals. Local farmers tend to plant rice before, after planting water chestnut, planting the latest but not the fall off. If you can plant early in time, the yield is high, and if you plant late, the yield is low. Before and after the winter is digging young water chestnut, general mu yield 20-25 quintal, high up to 30 quintal or more. Second, the main characteristics and economic value of water chestnut is an annual herbaceous plant, belongs to Salixaceae. The ground is clustered slender tubular metamorphic stems, hollow with nodes, leafless. Flower spikes are gathered at the end of the stem like a fist. Flowers brown. Fruit for the underground bulb, a weight of more than 10 to 20 grams or so, the bulb tip with about 1 cm long main bud, around with side buds 3-4. Shaoxing water chestnut has two varieties of big red robe, purple wupi. The former meat crispy moisture, suitable for raw food, or processed into water canned horseshoes. The latter type of meat hard, less water, but high starch content, should be processed into horseshoe powder, white crystal, smooth and delicate, comparable with the lotus root powder, diamond powder, known as "three yuan, the first" by overseas Chinese. Mostly used for summer cakes and cold drinks food ingredients. Water chestnut is cold and slippery, taste sweet and cool, have peace in the gas, appetizing food, heat and thirst and other effects. Shaoxing folk will water chestnut and sugar cane old man **** cooking is a good medicine to clear the fire detoxification, applicable to dry throat, indigestion, fecal dryness and other diseases. Whenever the lunar New Year, shaoxing countryside also use water chestnut burn lotus root with red dates, commonly known as "rich", in order to take the next year auspicious meaning. Water chestnut per 100 grams of edible part, containing 15 grams of protein, fat 0.1 grams, sugar 2l grams, calories 9l kcal, and contains iron, phosphorus, calcium and other trace elements, so the right amount of food can be hungry, but also beneficial to the body. Third, the conditions and cultivation techniques in the cultivation management, Shaoxing farmers choose a large garden whole, the main buds full of undamaged as the seed water chestnut. Seedling beds should be covered with river mud 4?inch. According to about 2 inches of plant row spacing to seed water chestnut sown into the seedbed, the top buds face up. After sowing, put up a trellis to cover the shade, and cover it early and harvest it late. About ten days before transplanting, the seedling length of 3-4 inches, go to the shed refining seedlings. Before transplanting, the field is y turned and fertilized, and then planted 3000-4000 plants per mu. Just transplanting water should be shallow, about l inch or so, in the tillering stage of irrigation water deep to 2-3 inch or so. To the cold dew stop irrigation. To the winter to spring period for the harvest season. Shaoxing rural harvest in winter called winter touch, spring harvest called spring touch. Often digging with an iron hoe while picking by hand, because water chestnut grows in different depths, often a picking is not clean, so there is a "nerd according to the water chestnut" argument. In order to maintain the quality of water chestnuts, when harvesting, pick off the young, broken skin, with soil pile on the soil indoors. The height and width are not more than 3 feet, and the pile is sealed with mud around the surface, so that it will not dry out and freeze, and heat and deteriorate. This can be stored to the following year in April and May, some according to this method to stay in the seed, to the seedling only when the seal. In recent years, Shaoxing water chestnut planting area has been sharply reduced, only Tao Yan, Yuebei and other places still have pieces of planting, the rest are just some sporadic cultivation, the county's annual planting area of about 900 acres, with a total output of about two million pounds or so.