The latest course of Maize planting techniques and methods

Corn, the largest food crop in China, is a C-4 plant in biology, but the bracts use C3 model for photosynthesis, monoecious. The main producing area is located in the third largest corn belt in the world-the Songliao Plain Corn Belt in China. The total planting area of corn is about 1249.35 square kilometers, also known as maize, Baogu (Baogu stick), bracts and sticks. It is called corn in Cantonese and rye in southern Fujian. It is an annual grass of the family Gramineae. It is an important food crop and an important source of feed. It is also the food crop with the highest total yield in the world.

Maize variety selection

Knowing how to select good maize varieties is a key issue related to the increase of autumn yield and income. The following principles should be followed when selecting improved corn varieties:

1. Seed selection according to the conditions of heat resources: the local heat resources are related to the growth period of maize varieties. The maize varieties with long growing period have good yield performance and high yield potential, and the local heat and growth period should meet the needs of full maturity of the varieties. If the heat is sufficient, the corn varieties with longer growth period should be selected as far as possible, so that the production potential of the excellent varieties can be brought into full play. However, too much pursuit of high yield and the use of maize varieties with too long growth period will lead to the lack of full maturity and grain fullness, which will affect the nutrition and quality of corn. Therefore, the selection of maize varieties should not only ensure the normal maturity of corn, but also can not affect the timely sowing of the next crop. The topography is related to the ground temperature, and the hilly land temperature is high, so it is appropriate to choose late-maturing varieties or mid-late-maturing varieties with long growth period, mid-late-maturing varieties in flat land and mid-early-maturing varieties in depression.

2. According to the local production management conditions, the high yield potential of maize varieties is related to the production management conditions, the varieties with high yield potential need good production management conditions, and the varieties with low production potential need relatively low production management conditions. Therefore, the maize varieties with high yield potential and high yield potential can be selected in the areas with high level of production management, fertile soil and abundant water source. On the contrary, the varieties with lower production potential but better stable performance should be selected.

3. seed selection according to the previous planting: the yield and income of the variety of maize is directly related to the previous planting. If soybean is planted in the previous crop, the soil fertility is better, and high-yield varieties should be selected; if corn is planted in the previous crop with good growth and high yield, this variety can continue to be selected; if the previous corn is infected with a certain disease, the varieties prone to this disease should be avoided in seed selection. In addition, the same variety can not be planted in the same plot for three or four years, otherwise the land will be barren and the varieties will be degraded.

4. seed selection according to disease: disease is the nemesis of high yield of maize, which is mainly related to soil. The soil nutrients are not balanced and the soil temperature is abnormal, so the varieties which are not suitable for growing under this condition should be avoided in seed selection. For example, "Denghai 9" is only suitable for growing in plots with balanced soil nutrients and high maturity.

5. Seed selection according to seed appearance: the purity and quality of maize varieties directly affect the yield of corn. When the purity of first-grade corn seeds (purity 98%) decreases by 1%, the yield will decrease by 0.61%. The selection of high quality varieties is a favorable guarantee for high yield of maize. The high-quality seed bag is sealed at one time, with the name and detailed address and telephone number of the seed company; the production date, purity, moisture and bud percentage are clearly marked on the seed label; and the shape, size and color of the seed are neat and consistent.

6. Seed selection according to local precipitation and accumulated temperature: according to experience, the amount of snow in last winter is small, the winter is not cold, the next summer rainfall will be more, the accumulated temperature will not be high, and the varieties with too long growing period will not have enough accumulated temperature, which will affect the maturity. On the contrary, there is a large amount of snow in last winter, very cold in winter, less rainfall in the following summer and high accumulated temperature, so it is easy to choose varieties with strong drought resistance, and some mid-and late-maturing varieties can be planted in the depression.

First thing in the morning, three times before drought-resistant precision sowing.

Drought-resistant precision sowing and preservation of seedlings is the premise to achieve high yield. The technique of catching up with three times in the morning is to sow seeds early by grabbing the soil moisture at the right time, before the early spring (making full use of anti-slurry water). Topdressing was long before the summer drought (so that the high efficiency period of fertilizer and water needed for corn coincided with the peak of the rain and heat period in July and August), and the corn matured before frost (making full use of effective accumulated temperature to promote early ripening and yield increase).

1. The early sowing time is between April 15 and 25, and the best time is 20 days. According to the soil temperature index, the soil temperature of 10 cm can be sown when the soil temperature is stable between 7 and 8 ℃.

2. Seed drought resistance treatment: corn biological seed soaking agent and drought-resistant and water-retaining agent were used (refer to variety description).

3. Sowing quality: ensure appropriate depth, consistent soil cover, improve the uniformity of seedling emergence, and achieve the whole seedling. With the increase of yield, the effect of sowing technology on yield was gradually enhanced. Sowing techniques include selection of seed treatment, soil moisture preparation, reasonable density, sowing method, sowing amount and sowing depth, etc.

Corn sowing technology

The main results are as follows: 1. Seed treatment: the sunburned corn seeds absorb water quickly, germinate early, emerge neatly, the emergence rate is high, and the seedlings are stout.

2. Seed soaking and seed dressing: soaking seeds in clear water is mainly to supply water and promote germination. The main chemical agents for seed soaking are potassium dihydrogen phosphate and trace elements, but if the concentration of seed soaking is too high or the soaking time is too long, the seed is easy to be poisoned and the germination rate is reduced. Seed dressing with pesticides can control the harm of diseases and insect pests. Seed coating is to coat the seed with a potion. The coated seeds have the ability of disease resistance, insect resistance and promoting rooting and germination after sowing, and should be used symptomatically for local diseases and insect pests.

3. Prepare soil moisture carefully: soil moisture is the key to affect the quality of seed emergence. The soil moisture is good, the land is flat, the sowing depth is easy to be consistent, and the seedlings emerge neatly and evenly. An important part of preparing soil moisture before sowing is the adjustment of soil moisture. In Huang-Huai summer and interplanting summer corn areas, seasonal drought often occurs after wheat harvest, which worsens the soil moisture during sowing; therefore, watering wheat yellow water is often used to supplement soil moisture in production.

4. Reasonable close planting: the characteristics of varieties should be considered in reasonable density. Secondly, if the soil fertility and the amount of fertilizer application are large and reasonable, the suitable density is large. In areas prone to drought and no irrigation conditions, the planting density should be sparse.

5. The calculation of sowing amount: seed amount (kg) = sowing density × number of grains per hole × grain weight × area. We should focus on developing corn precision sowing technology and improving sowing quality.

6. Sowing depth: 5~6cm is generally suitable for sowing depth. In the clay with good soil moisture, it should be sown shallowly, and 4~5cm is suitable. The loose sandy loam should be sown deeply, and 6~8cm is suitable. If the soil moisture is large, it is not suitable for deep sowing, but the dry soil should be sowed properly.

7. Suppression after sowing: after covering the soil after sowing, it should be suppressed properly, when it is dry, it should be severely suppressed, and when the soil moisture is too much, do not suppress.

8. Suitable application of seed fertilizer: proper application of seed fertilizer can provide sufficient nutrients for seedling growth, promote seedling growth and enhance resistance to adverse factors such as drought, low temperature, disease and so on. Seed fertilizer includes a small amount of nitrogen fertilizer, phosphate fertilizer, potassium fertilizer and trace element fertilizer. The use of seed fertilizer should be controlled and isolated so as to avoid burning seedlings. General mu application of 5~8kg diammonium phosphate, the effect is good.

9. Post-broadcast management

If there is a lack of plants and few seedlings after sowing in ①, but there is no obvious phenomenon of lack of rows and broken ridges, two plants can be left near the holes of the missing plants to make up the density when the seedlings are fixed, and shade tolerant crops such as soybean and potato can also be planted in the areas with serious lack of rows and broken ridges. If only half of the seedlings emerge, you can sow intercropping crops. When the seedling is less than half of emergence, it is recommended to destroy the seed and rebroadcast.

② corn likes temperature and light. The lowest temperature of maize seed germination is 6 ~ 7 ℃, but the germination speed is very slow and it is easy to rot by bacteria and fungi in the soil. In some places, in order to avoid the effects of summer drought and poor pollination caused by the high temperature season, they sow seeds prematurely at the beginning of spring. because the soil temperature is low and the seasonal temperature is not stable, it often takes 20 days from sowing to emergence, such as overcast rain or cold wave. Often cause uneven emergence or mildew of seeds. Corn seeds germinated quickly and neatly at the temperature of 10-12 ℃, which was taken as the lowest temperature index for the beginning of sowing.

The low temperature resistance of ③ maize seedlings was stronger than that in the later growth stage. If the low temperature is 0 ℃, the seedlings will not freeze to death, but the seedlings will be damaged under the short-term low temperature of-2 ℃. If the temperature rises quickly and the seedlings are managed in time, the seedlings can return to normal growth in a few days. If the low temperature continues to grow, the seedlings will freeze to death. When corn grows 4-5 leaves, it can still resist slight frost, and then the cold resistance decreases gradually. The reason for the slow growth of seedlings caused by low temperature was the slowing down of root metabolism. When the temperature dropped to 4: 5 ℃, the root system stopped growing completely. In agricultural production management, ridging sowing to increase sunshine area or plastic film mulching to increase soil temperature is of great benefit to promote root development.

Reasonable close planting of corn

1. Enlarge the line spacing: change the traditional line spacing from 60,65cm to 120,130cm (also equal to interplanting). Concentrate the fertilizer and seedlings on the utilization area of 1 stroke 2. If the density is increased, 60000 ~ 62000 seedlings per hectare will be preserved, and the number of harvested plants will be 58000.

2. Enlarging the distance between plants: from the conventional ridge, using a distance to cover multiple plants (3 plants in 80cm or 4 plants in 100cm), 60000 ~ 62000 seedlings per hectare, and 5.8 ~ 60000 plants must be harvested.

Scientific fertilization technology

The combination of organic fertilizer and chemical fertilizer. 80 cubic meters of high-quality farm manure is applied per hectare, N 75% is required to be applied as base fertilizer, 25% as topdressing, and the depth of base fertilizer is 1520 cm (to avoid burning young roots with urea slow-release agent). The fertilization standard should be adjusted according to the local soil fertility, fertilizer and water conditions. The standard is 130% of the usual amount used all the year round (increase the regular dosage by 30%).

Control of diseases and insect pests

The seeds are coated with a coating agent, and the coating agent is selected according to the proportion of the ingredients needed locally. According to the instructions, the use must meet the dosage standard in order to effectively prevent and cure it. In order to prevent the occurrence of maize dwarf disease, Maize rough shrinking Ling was sprayed once at 6-8 leaf stage of maize.

Leaf spot was sprayed with 75% chlorothalonil 500 times 800 times or 50% carbendazim 500 times at the male ear stage of corn, and was sprayed again at intervals of 10 to 15 days. Timely release of Trichogramma to control corn borer, can also use 50% phoxim or 50% methamidophos, 50% 1605 0.5 kg mixed with arsenopyrite 50 kg, in the trumpet mouth period into the heart leaf.