The original small days in the portable space

Chapter 20 Corn
Although Aqi has a lot of food and seeds in her hands, she still hopes to achieve her expectations through hard work. It is winter now.Aqi has nothing else to do, so she just sits in the room all day and reads books, such as a complete collection of food, a complete collection of fruits and vegetables... and so on.

[-]. Land selection and land preparation
Corn has a well-developed root system and strong adaptability. The requirements for soil types are not strict, and it can be planted on fertile land and lean land.However, corn plants are tall, have many roots, and many branches. They need to absorb the most water and nutrients from the soil. Therefore, it is necessary to choose flat terrain, deep soil layers, loose texture, good permeability, and above-average fertility. Only dry land (field) or gentle slope land with better fertility can obtain higher yields.Before planting, the land should be plowed carefully to make the soil soft, finely crushed and leveled before sowing.

[-]. Selection
The selection of superior corn hybrids is one of the key measures to obtain high yields of corn.The production can be increased by 10%~20% without increasing the input.

玉米播种前要精选种子。选留籽粒饱满、大小均匀、颜色鲜亮、发芽率高的种子，去除秕、烂、霉和小粒。将经过粒选的种子晒1~2天，并药剂拌种或包衣，包衣剂可选用20%福克悬浮剂或选用5。4%11吡戊玉米种衣剂以控制苗期灰飞虱、蚜虫、粗缩病、纹枯病；玉米免耕栽培技术药剂拌种可选用辛硫磷或毒死蜱等以杀死地老虎、金针虫、蝼蛄、蛴螬等地下害虫。？
[-]. Sowing

1播种时间：当5—10厘米地温稳定在8—10℃时播种，根据不同播种期试验，以4月25日5月5日播种为最好，这期间播种，玉米出苗快、抗性好、产量性状优。

2墙种密度：根据品种熟期、类型、地力确定密度，一般玉米亩株数应在2600—3300株左右。耐密品种亩保苗3500—4500株。

3. Sowing method: There are two forms of ditching drill and digging soil and hole planting. The seed quantity per mu is calculated according to the number of plants per mu and the weight of 2 seeds for drill sowing. The seeder is properly adjusted. It is advisable to sow seeds with precision.The benefits of precision sowing are 3) plant saving; [-]) less involvement and less damage to roots during thinning; [-]) saving nutrient consumption.

4. Sowing depth: Determine the sowing depth according to the soil moisture. Generally, it is about 3 cm. The principle is that it should be shallow rather than deep. In case of drought, when the soil moisture is not good, you should dig deep trenches and cover the soil shallowly so that the seeds can fully receive the tide. Soil, if the water content of the soil is high, it should be dried according to the situation after sowing, and then covered with soil and vibrated to avoid soil moisture, which will cause compaction and form a hard shell, which will affect the emergence of corn and ensure the emergence of seedlings at one time of sowing.

[-]. Reasonable dense planting

采用宽窄行种植模式，宽行80厘米，窄行40厘米。种植密度应根据品种特性和地力水平而定。郑单958一般地力3500—4000株，亩，中高肥力4000~4500株庙；浚单20一般地力3500—3800株庙，高肥地3800—4200株庙；鲁单981一般种植密度3000株庙左右。（平均行距60厘米，株距7。5寸，密度约为4500株，亩；株距8。5寸，密度约为4000株庙；株距9，5寸，密度约为3500株/亩）
Five, field management

1. Break ground and introduce seedlings.When corn emerges, it is necessary to check the emergence of corn in time.Corn single-seed sowing cultivation technology Take out the unearthed seedlings from the film at 6-10 every morning, and seal the film mouth with soil. ?
2?Check the seedlings and supplement the seedlings.Check the seedlings and replenish the seedlings in time after the emergence of corn seedlings.When sowing in the field, spare seedlings should be sown on the field.300 plants per mu, used for transplanting seedlings.

3?Thinning and Dingmiao.After the 2-3 leaves of corn emerge, start thinning and remove the weak seedlings; when the 3-4 leaves of the seedlings are unfolded, the seedlings can be fixed, and the strong and uniform seedlings can be kept.The standards for strong seedlings are: wide leaves, many deep roots, flat and thick stem bases, solid growth, and dark green seedlings.

4?top dressing.When the corn enters the vigorous growth period, that is, from the jointing period to the big bell mouth period, the ear fertilizer should be topdressed.General mu topdressing urea 25 ~ 30kg.The topdressing method is: use a corn seeder to punch holes in the middle of each nest of corn, and apply fertilizer; or dissolve the fertilizer in 150-200kg of water to make liquid fertilizer, and use a pot to irrigate about 50ml per hole.Topdressing holes should be sealed with soil in time to prevent fertilizer loss.

5?Add zinc fertilizer and strong cable.During the jointing stage of corn, 0kg of zinc sulfate solution of 05%-0% was used for foliar spraying, and the whole growth period was sprayed twice.During the big trumpet mouth stage of corn, use 10ml of maize extinctin per mu and spray 50kg of water on the leaves to reduce the plant quotient and form healthy plants.

[-]. Pest control
1. Corn diseases: mainly corn head smut, which is a soil-borne disease caused by systemic infection at the seedling stage.Control methods: choose disease-resistant varieties, implement stubble rotation, remove diseased residues, etc.Seed coating can also be applied to prevent and control underground pests and disease infections. In areas with severe disease, fungicides such as Li Kexiu or Fenxiu Ning should be added.

2. Corn pests: mainly armyworms.corn borer. (I) Chemical control: 5% parathion granules can be applied to the heart leaves in the middle stage of the heart leaves to achieve the effect of one drug against double insects. (2) Biological control: Trichogramma and BT powder are used for control. ① Trichogramma is used to control corn borer. Release bees when the number of eggs of 1 corn plants in the field reaches 2-7000 pieces. For the first time, 8000-7 bees are released, and the second time is released every 12000 days. The number of bees released per mu is 13000-100. ② Sprinkle Suterin powder in the big trumpet mouth period of corn, mix 20 grams of BT powder per mu with 2 kg of sandy soil, and put 3-[-] grams per plant within the trumpet day, which can effectively control corn borer and armyworm.

[-]. Harvest

When the corn husks turn yellow (pale), only 80% of the yield per mu is formed, and 20% of the yield needs to be matured in about 15 days.When the ear grain milk line disappears and a black layer appears at the base of the middle grain, it is the best harvesting period for corn, and the yield is the highest.

Aqi looked at the book on growing food that she bought from the space, and while thinking about it, she always told everyone in the most vernacular language that it is not enough to plant the seeds, and there are many later things.

(End of this chapter)