How to plant high yield water chestnut? How to harvest? What are the storage methods?

Chestnut is also known as horseshoe, water chestnut, chestnut, black taro, Cardamine, pear and so on. It is a cluster aquatic herb belonging to the family Cyperaceae. It is eaten by underground bulbs with crisp meat, rich in starch, and can be used as fruits or vegetables. It can also be made into canned or starch, candied fruit, which is favored by consumers. How to plant water chestnuts with high yield? How to harvest? What are the storage methods?

I. Origin distribution of water chestnut

Water chestnuts are native to India. There are about 150 species of water chestnuts in the world, especially in tropical and subtropical regions. Cultivation has been recorded in China since the Western Han Dynasty. At present, there are more than 20 species and some varieties, mainly distributed in low-lying areas such as Guangxi, Jiangsu, Anhui, Zhejiang, Fujian, Guangdong, Hunan, Hubei, Jiangxi and Guizhou, and also in some areas of Hebei. Baihu Town, Lujiang County, Anhui Province is rich in high-quality water chestnuts, which is the largest "hometown of water chestnuts" in China. Qingshan Town, Lipu County, Guilin City, Guangxi is a nationally recognized "hometown of horseshoes". Lechang water chestnut in Shaoguan area of Guangdong Province is famous for its large size, thin skin, tender meat, sufficient moisture, sweetness, no residue and crispness and delicacy. In addition, Maoli Town, Shayang County, Jingmen City, Hubei Province is also a producing area of water chestnuts, which has been sold overseas and famous.

Second, the growth environment of water chestnut

Water chestnuts are born in ponds or cultivated in paddy fields. Bulbs, also known as fruit balls, are used for asexual reproduction. Like warm, wet and cold, it is suitable to grow in loam where the plough layer is soft and the subsoil is solid. In cultivation, a ploughing layer of 20 cm to 25 cm is required, which is not only conducive to the growth and development of the corm, but also does not cause the corm to drill deep, and the ontogeny is uniform and uniform, and it is also conducive to digging. The plough layer is too sticky, which is not conducive to the expansion of the corm, too much humus, lower sugar content of the corm and poor sweetness. It is suitable to grow in shallow water. In terms of nutritional requirements, it requires less nitrogen fertilizer and more phosphate fertilizer. Adequate light is required throughout the growing period.

3. Seedling raising techniques of water chestnut

1. Chestnut selection: water chestnut is propagated through stolons. Before sowing, one by one, the epidermis is undamaged, the lateral buds of the terminal buds are strong and sound, the skin is dark brown, the single corm weight is more than 15 grams, and the bulbs with the characteristics of the cultivated varieties are used as seeds. Before sowing, soak in the 500-fold solution of more than 50% carbendazim wettable powder for 24 hours to kill surface bacteria, and about 15 million 20 kilograms per mu of field need to be planted.

two。 Seedling raising time: the seedling raising time of water chestnut depends on the transplanting period. Because of the low temperature in the early stage, the early water water chestnut began to raise seedlings 40-45 days before transplanting (from late March to early April), and the late water water chestnut seedlings were raised 20-25 days before transplanting because of the higher temperature. In the middle and lower reaches of the Yangtze River, seedlings are usually raised during the Qingming Festival to Grain Rain. Indoor sprouting is carried out before breeding, and then planting and pseudo-planting are carried out in paddy fields.

3. Cardamine seed sprouting: the method of indoor sprouting is to spread a layer of straw of about 10 centimeters on the ground, arrange the seed shepherd buds upward on the straw, stack them with 3 or 4 layers, and cover them with straw once every morning and evening. 10 days later, when the buds grow to 3 centimeters, you can transplant the seedlings to the seedling field for planting.

4. Seedling field preparation: seedling fields should be ploughed, raked and leveled in places where drainage and irrigation are convenient and fertile and loose, and furrows should be left around them and ridges should be built, because during this period, the nutrition of water chestnut growth mainly comes from water chestnut bulbs, and seedling fields generally do not need fertilization.

5. Planting and seedling raising: the bulbs that promote budding are discharged into the seedling pond one by one, and the bulbs are pressed into the mud, the row spacing is 6 × 6 cm, the bud head is required to be up and up, high and low, and the water layer is kept at 1 cm in the field. After 15-20 days, when the seedling is about 10 cm high and has 5-6 leafy stems, it can be pseudo-planted.

6. False planting of water chestnut: false planting of water chestnut is to separate the seedlings, expand its row spacing, facilitate centralized fertilization and management, and mainly meet the needs of planting water chestnuts with rape stubble or wheat stubble in the south. The specific method of pseudo-planting is that 20-25 days after planting, the corms of 10 cm and 15 cm leafy stems are transplanted into the water chestnut seedling field and planted into the corms according to the row spacing of 30 cm × 40 cm, which is not only beneficial to rooting, but also expand the nutritional area of the seedlings.

7. Seedling management: the seedling field after the transfer of water chestnut seedlings had better maintain a shallow water layer of 2 cm to 3 cm, which can increase the soil temperature and promote the growth of seedlings. About 15 days after seedling transfer, 20 kg of N, P and K ternary compound fertilizer was applied per mu, which should not be concentrated near the root so as not to burn the root of the seedling. After 30-40 days, when the seedling height is 35-40 cm and the leafy stem is more than 0.5 cm in diameter, the seedlings can be planted in the field.

IV. Planting techniques of water chestnut

1. Soil preparation and fertilization: it is best to choose paddy fields with sufficient sunshine, loose topsoil, solid subsoil, about 20 cm plough layer, adequate water source, convenient irrigation and clean water. Before planting, the field should be ploughed about 15 cm deep, and then applied with base fertilizer. The reference standard of fertilization is to apply 3000 kg of rotten pig manure, 30 kg of calcium superphosphate, 10 kg of potassium chloride and 15 kg of ammonium bicarbonate per mu, and finally rake the soil into mud paste.

two。 Timely planting: the planting time of water chestnut in the middle and lower reaches of the Yangtze River can be arranged from late May to early June. Carefully dig out the seedlings before planting and wash off the soil. The best row spacing of water chestnut is about 30 × 50 cm, with 1 plant per hole and 2500 × 3000 plants per mu. The depth of planting water chestnut should be suitable, and the depth of buried water chestnut is 5cm and 7cm.

5. Planting techniques of water chestnut

1. Seedling stage: the period from living plant to tillering and pre-tillering is called seedling stage. Water chestnut is an aquatic crop, so the shallow water layer should be kept at 3-5 cm at seedling stage. Water chestnut began to grow 10-15 days after planting. When the old leaves of chestnut seedlings withered and died, the seedlings with yellowing stems, rotten seeds and withered leaves of weeds were put into the field, which was beneficial to the growth of new roots. At this time, urea can be applied once, generally 10 kilograms per mu of urea to promote early tillering of water chestnut.

two。 Vegetative period: weeding in the water chestnut field for 2 times in the tillering stage, combined with weeding for the second time, topdressing 5 kg urea per mu to promote the setting of water chestnut. From the Autumn Equinox to Cold Dew, during the period of vigorous growth of the bulb, it is better to deepen the water layer and keep the water layer within 6-9 cm. During this period, water chestnut stem blight and water chestnut white grain borer often occur. For water chestnut stem blight, 50% carbendazim wettable powder 500 × 1000 times liquid plus 70% methyl thiophanate 800 times solution 40 kg spray per mu. The control method of white grain borer is to spray 50 kg water with 98% Shamindan 100g.

3. Mature period: in the corm maturity period, that is, about 20 days before harvest, irrigation should be stopped, so that the leaves turn yellow, gradually dry up, ready for harvest. There is no other management during this period, as long as livestock harm is prevented.

VI. Harvesting methods of water chestnut

1. Harvest time: the harvest time of water chestnut can be from Frosts Descent to the Spring Equinox in the second year. The early harvested bulbs are tender, light-skinned and not resistant to storage. From the Winter Solstice to Lesser Cold, the color of the bulb skin changed to reddish brown, the taste was the sweetest, and the sugar content was the highest, so it was the most suitable for harvest at this time. After that, the sugar content of the corm gradually decreased, the epidermis thickened, the skin color deepened and became dark brown, and a layer of yellow clothing was produced under the epidermis, and the quality became worse, so the commercial bulbs should be harvested before overwintering.

two。 Harvest method: generally release the field water the day before harvest, because the bulbs are mainly concentrated in the soil layer of 9cm and 20cm, first remove the soil of the upper layer of 8cm, then pick out the soil of the lower layer, and carefully pinch out the bulbs with their hands (people call it "touching water chestnuts"). If you rush for seed stubble (such as rape stubble or wheat stubble), it should be drained 10-15 days before harvest and dug with a fork.

7. Storage methods of water chestnut

1. Vat storage: after the water chestnut is collected, it is spread out on the brick floor for 12-15 days, and after being properly dried, it is put into a large indoor pottery tank. The pottery jar should be placed in a dry and ventilated place with a storage capacity of about 80,100kg per cylinder, and the cylinder mouth full of water chestnuts should be capped. It should be noted that the water chestnut stored in the pottery jar has a strong respiration in the early stage of storage, and the cylinder head must be opened to facilitate ventilation and ventilation. In the cold and cold winter, the tank should be covered with a layer of straw to keep warm. In overcast and rainy weather, the cover should be opened in time due to high air humidity, and should be capped in time in hot and hot season to prevent dry rot caused by water evaporation in the water chestnut bulb. In the process of storage, the water chestnuts stored in the pottery jar should be checked every 25 to 30 days. According to this method, the shelf life of water chestnut can reach more than half a year.

two。 Kiln storage: if you use an old kiln for storage, 2.5% carbendazim or 40% thiophanate-methyl 400-500 times solution should be sprayed at the bottom and body of the kiln before storage. Spread a layer of fine soil at the bottom of the kiln, sprinkle a layer of dry fine soil on each water chestnut 20 cm thick, and spread a layer of soil on such a layer of fruit until 20 cm away from the kiln mouth. Fill the mouth with dry fine soil, and cover the top with 30 cm thick soil to form a steamed bread shape with high in the center and low around, covering the kiln mouth and pounding.

3. Sand storage: after the water chestnut is collected and dug, brick is used in the cool house or basement, and a buried pit is laid at the bottom of the pit with fine sand 5cm thick. Arrange the water chestnut bulb on the sand surface, cover the fine sand 3cm thick, and then discharge the water chestnut bulb. Such a layer is stacked with a height of no more than 1 meter. This method can also play a good storage and fresh-keeping effect.

4. Solution: remove sundries from the harvested water chestnut corms and quickly soak them in sodium hypochlorite solution for storage after cleaning. According to the experiment, when the temperature is 0 ℃ and the relative humidity is 90% 100%, the water chestnut bulb can be kept fresh for 10 months, and the storage period can reach 6-8 months under 5 ℃.

5. Storage: it is appropriate to choose the soil ground in the shady room, and its size can be determined according to the quantity of storage. First of all, spread a layer of dry fine soil on the ground, surrounded by a mat, or built into a pool with bricks, and then a layer of water chestnut dry fine soil, layer by layer.