Methods of corn planting
Sowing
The natural conditions of China's corn-producing areas vary greatly, according to the length of the local frost period, soil texture, soil fertility, planting month, choose the appropriate varieties, forage corn and horse-tooth hybrids with high yields. Also pay attention to the breeding of good seeds, the appropriate arrangement of seed field area.
Temperature: corn sowing period by temperature, humidity, the optimal temperature for seed germination is 25 ~ 30 ℃. The daily average of 18 ℃ or more during the pulling period. From tasseling to flowering daily average 26 ~ 27 ℃. Spring sown corn in 7.6cm within the upper layer stabilized at 15 ℃ for the best sowing period. North China summer sown corn in wheat or pea harvest in time to sow. Sowing depth, according to soil moisture for 2.5 - 10cm, to 5 a 6cm is most suitable.
Soil: corn in sandy soil, loam, clay soil can grow. Corn suitable soil pH 5 ~ 8, to PH 6.5 ~ 7.0 most suitable. Poor salinity tolerance, especially chloride ions are harmful to corn. Corn root system is developed, adaptability is also strong, it is not strict on the requirements of the soil type, but the corn plant is tall, root system, it has to draw a lot of water and nutrients from the soil, so generally we have to choose the terrain is relatively flat, the soil layer is deep, the texture of the loose, good permeability, fertility more than medium, water retention, fertilizer retention of better plots, in order to obtain a higher yield.
Reasonable spacing: 3 to 4 kg of seed per acre, 4000 to 6000 plants per acre. Planting method of forage corn. Single sowing, from planting to harvesting is easy to operate mechanically. Intercropping with soybeans, sock-feeding beans, peas, and hairy-leafed camas can increase protein yield per unit area.
Seeds: the corn seeds we planted are hybrid seeds, in common parlance, is a one-year seed (can not save the seed), mainly the use of its hybrid advantage, to improve the yield of corn, quality, and its resistance to disease and resilience, selecting the seed do not choose the next year's seed, the main thing is that the germination is low.
Nutrition: the role of basal fertilizer is mainly to fertilize the ground, improve the physical properties of the soil, loosen the soil, conducive to microbial activity, timely supply of nutrients to the seedling, promote root development, and create good environmental conditions for the cultivation of strong seedlings.
Management
The corn plant is tall, with high seed and stem yield, requiring fine management. Fertilizer, irrigation, chemical hoeing and pest control are key technical measures in the management of high-yield corn cultivation. To obtain high-yield and high-quality corn, before sowing each mu of 2000?3000kg of high-quality stable fertilizer as a base fertilizer. At the time of sowing, apply 4?5kg/mu of sulfuric acid, 15?20kg/mu of calcium superphosphate, and 2-3kg/mu of chlorinated trees as seed fertilizer, and then apply nitrogen fertilizer during the period of nodulation, tassel production, male pumping, and blossoming and grouting. The whole life cycle of nitrogen 10-20kg/mu. N: P: K for 1: 0.5-0.8: 0.8. Corn likes semi-arid climate, but is very sensitive to water. A corn plant in the flowering period consumes about 2kg of water per day, 3?4m3 of water per mu per day, and 250?350m3 of water during the whole reproductive period. Different fertility of corn with different water needs. 10 days before to 10 days after staminate extraction is the most water demand in the life of the corn, the most sensitive period of water, known as? critical period of water demand? Irrigation is required during this period. Corn life in general to watering 3?4 times, according to different regions, the specific situation varies. Irrigation methods, China is now mostly furrow irrigation, border irrigation, the recent development of the use of sprinkler irrigation, drip irrigation, the latter two methods, both water saving, and irrigation uniformity. Corn does not tolerate flooding, in the high water table and southern rainfall areas, pay attention to drainage or take the ridge, the field of cultivation to prevent flooding.
Maize planting environment
Temperature
Maize is a warm crop, the whole life cycle requires high temperature. The biologically effective temperature for corn is 10°C. Seed germination requirements 6?10 ℃, below 10 ℃ germination slow, 16?21 ℃ germination flourish, germination optimal temperature of 28?35 ℃, 40 ℃ or more to stop germination. Seedlings can tolerate short-term -2 - -3 ℃ depending on the temperature. The nodulation period requires 15?27 ℃, the flowering period requires 25?26 ℃, the grouting period requires 20?24 ℃. Different corn varieties of temperature requirements are not the same, China's early maturing varieties require cumulative temperature 2000 - 2200 ℃; medium maturing varieties 2300 a 2600 ℃; late maturing products and 25OO - 28OO (3000) ℃. Most of the world's corn production areas are concentrated in July isotherms of 21 - 27 ℃, frost-free period of 120?180 days range.
Light
Maize is a short-sun plant and can flower and fruit under short-sun (8--10 hours) conditions. Spectral composition has a great impact on the development of corn, according to research in the daytime blue and other short-wave light corn development, while the morning or night to red and other long-wave light development. Corn for C4 plants, has a strong photosynthetic capacity, light saturation point is high, the general photosynthetic intensity of corn for 35--80mgCO2/dm2?leaf? hours.
Moisture
Corn's plant is high, the leaf area is large, so the water demand is also more. The optimal amount of precipitation during the growth of corn is 410?640mm, in drought affects the yield and quality of corn. It is generally believed that areas with less than 150mm in summer are not suitable for growing corn, while too much precipitation affects light, increases disease, collapse and weed damage, and also affects corn yield and quality. Although corn needs more water, but the relative water demand is not too high, transpiration coefficient of 240?370, lower than barley (280 a 400), oats (340 a 500), purple flower first clear (831), clover (797), water consumption is more economical. Corn has a strong root system that fully utilizes the moisture in the soil. In high temperatures and dry air, the leaves curl upward, reducing the transpiration area, so that water absorption and transpiration are properly balanced.
Soil
Corn is not very strict on soil requirements. Loose soil, deep soil, organic matter-rich black calcium soil, chestnut calcium soil and sandy loam, out in the range of 6 a 8 can be planted corn. Corn seedlings can grow in soil containing NaCl 0.21%, greater than plant death. Corn plants contain 16 kinds of elements, except C, H2O2 from CO2. and are to be absorbed from the soil. Those needed in larger quantities are N, P, K, S, Ca and Mg, and those needed in smaller quantities are Fe, Mn, Zn, Cu, Ba and Cl2. Corn from 10 days before pumping male to 25?30 days after pumping Hua is corn in the fastest accumulation of material, the most fertilizer absorption stage, this stage of absorption accounted for the total absorption of fertilizer 70?75% of the N, 60?70% of the P and 65% of the K. Each production of 100 pounds of maize kernels need to be NI.75 a 2.22kg, H2PO40.59 - 0.85kg and K2o1.5?1.84kg. The ratio of the three elements is 2.6:1:2.
Maize cultivation technology
A, cultivation season
To spring corn (January 25 ? February 10) the highest yield; followed by autumn planting (August 25 ? September 10); again winter planting (October 20 ? January 10); the most inferior is summer planting (April 25 ? May 10). In short, the choice of the best sowing date of corn, according to the use of corn and land use, stubble arrangement to determine. Feed corn is suitable for spring and fall planting.
Second, the selection of land, land preparation and the application of adequate fertilizer
1, the selection of land
Corn is a preferred fertilizer, good temperature and heat, oxygen demand, afraid of waterlogged crops, too acidic, too viscous and infertile soils will make the corn grow poorly. Therefore, it is best to choose a convenient drainage and irrigation, easy to manage, PH6.5?7 between the fertility of more than medium loam or sandy loam is appropriate.
2, land preparation and base fertilizer
A good ground preparation is a prerequisite for the preservation of seedlings. After selecting the ground for deep plowing and harrowing, generally to do two plows and two harrows, the cultivation layer is more than 30 cm deep, in order to achieve? The ground is flat, the soil is fine, the moisture is sufficient, the fertilizer is high? The quality of land preparation is required. After the ground according to the double row planting spacing of 120?140 cm line ditching, and per mu of rotted farmyard manure 1000 kg, 50 kg of soybean cake and 50 kg of calcium superphosphate to do the basal fertilizer in the ditch; in order to drainage and irrigation, combined with the ground should also be ditching for the beds, repair the four sides of the drainage ditch. Requirements to achieve bed flat ditch straight, ditch ditch, drainage and irrigation smooth.
Third, seed treatment and sowing
1, the selection of good seed
Suitable for local seed should be high-yield and stable yield, good quality, disease resistance and anti-pouring, but also suitable for the market demand, the market is good. Currently feed corn selection? Yedan 4? The current feed corn selection is the Yedan 4, the Yedan 13. Yedan 13? The current feed corn choice is? Zhongdan 321? and other varieties. The choice of fresh corn is? Sweet glutinous 1? and Suyu No. 1. Suyu 1? and other specialized varieties. Generally, the amount of seed per mu of live field 1500?2000 grams.
2, seed treatment
3?4 hours of sunshine before sowing, generally with 50?55 ℃ warm water soaked seeds 10?15 minutes, cooled down and then soaked 6?8 hours, and then rinsed with water 1?2 times can be sown.
3, sowing specifications
The yield of corn comes from the use of light energy and ground power, within a certain range, the larger the leaf area coefficient, the higher the utilization of light energy, the higher the yield, therefore, reasonably dense planting in order to be high yield. Planting density must be considered from the variety, sowing period, soil fertility, cultivation conditions and other factors. There are two types of corn plant type: spreading type and compact type. Spreading varieties should be sparsely planted, generally mu planting 3000?3500 plants. Compact varieties should be densely planted, generally mu planted 4500?5500 plants. Corn seeding methods mainly have two kinds of row spacing and wide and narrow rows. Equal spacing planting specifications is 75 centimeters between rows, compact varieties spacing in 17?20 cm, spreading varieties spacing in 25?30 cm. Wide and narrow rows of planting specifications is 140 cm wide rows, narrow rows of 40 cm, compact varieties spacing 15 cm or so, spreading varieties spacing 20 cm or so. At present, the province to promote the planting of fresh corn plant type for compact, suitable for dense planting, general mu planting 3500?4000 plants. Planting method mainly using wide and narrow rows of planting, wide rows of 70 centimeters, narrow rows of 40?50 centimeters, 30 centimeters between plants.
4, sowing
The province planted corn due to higher temperatures, generally take live cultivation, and less use of seedling transplantation. The specific method is to start the bed planting, bed width 120?140 cm (wrapped ditch), bed height of about 20 cm or so, open two rows on the bed spaced 50?60 cm shallow ditch, will have been treated with a good seed per point double sown in the ditch (according to the plant spacing), the side of the sowing side of the cover soil, cover soil 1 inch and tread solidly.
Fourth, the law of fertilizer
Corn on nitrogen, phosphorus, potassium demand is the most, the whole life cycle of the three elements of the absorption of nitrogen is the most, followed by potassium, phosphorus is less. Therefore, the fertilization of corn to increase the main application of nitrogen fertilizer, with the application of phosphorus and potassium fertilizer. Generally speaking, the seedling stage (1?6 leaves) growth is slow, the plant is small, the absorption of nutrients is also less, this time the amount of fertilizer should account for about 10% of the amount of fertilizer. The jointing to flowering (7?16 leaves) growth is very fast, this is the male and female spike formation and development period, the absorption of nutrients fast, the number of plants need nutrients critical period, at this time to supply sufficient nutrients, can promote spikes, spikes big. At this time the amount of fertilizer should account for about 60% of the total amount of fertilizer, later (after 17 leaves) absorption rate gradually slowed down, absorption is also reduced. The amount of fertilizer applied should be about 20% of the total fertilizer. Nitrogen, phosphorus, potassium application ratio is generally about 3:1:2.8. Phosphorus and potassium fertilizers should be applied in the early stage. If the amount of fertilizer is insufficient, it should be used mainly in the pulling and flowering period.
V. Field management
1, seedling management
Corn seedling is rooting and leafing and stem, node, leaf differentiation and formation of nutrient growth period, most of the root system is formed at this time. The main goal of seedling management is: to promote the development of the root system, cultivate strong seedlings, so that the seedling full, seedling flush, seedling strong, for the fertility of the ear grain stage to lay a good foundation.
(1) set seedlings, between seedlings: master? To the weak and strong, between the dense storage thin, directional, stay even, stay strong seedlings? The principle of the seedling is generally carried out in 5 real leaves, each hole to stay a strong seedling, at the same time to check the seedling seedling, with the soil to move the seedling, and pouring enough root water to ensure that the seedlings survive. If the lack of seedlings is too much, can be used to replenish the seed solution.
(2) Plowing and weeding: corn seedling plowing can be carried out 1?2 times, and combined with fertilization, appropriate soil. The depth of the plowing requirements to achieve shallow seedlings, rows in the deep, shallow before the seedling, deep after the seedling, while paying attention to the prevention and control of pests and diseases.
(3) water and fertilizer management: in 5?6 leaves, the first application of seedling fertilizer, urea 7.5?10 kg per mu, in the middle of the bed furrow strip, and then cover the soil. Seedlings such as water shortage, should be timely irrigation, preferably furrow irrigation. In the case of rainy days, wet soil and waterlogging, attention should be paid to open deep ditches to drain the water and improve soil aeration conditions.
2, the management of the spike period
The spike period field management objectives are: attack culm, attack spike, strictly prevent the lack of water off the fertilizer, so that the plant is neat, short and thick stem nodes, leaf blades wide and thick, the root thickness is more than the amount of male and female spikes develop well.
(1) water and fertilizer management: in 8?9 leaves, the second fertilizer, that is, the application of straw tapping fertilizer, the amount of fertilizer accounted for about 25% of the total amount of fertilizer, 10 kg of composite fertilizer per acre plus 7.5 kg of potassium chloride, fertilizer mode for strip application. In 14?15 leaves (big trumpet period), the third fertilization, that is, the application of tapping spike fertilizer, the amount of this fertilizer accounted for about 35% of the total amount of fertilizer, per mu of compound fertilizer 20 kg plus 10 kg of potassium chloride, combined with the large cultivation of soil application. In 9 leaves and 15 leaves, respectively, an extra-root fertilizer, mu with 50 grams of rare earth or 800?1000 times potassium dihydrogen phosphate spray. Corn from nodulation to tassel plants began to enter the vigorous growth, water needs, especially before and after the male is the critical period of corn water needs, this time the lack of water, stunted, male and female flowering is not coordinated, affecting the pollination, resulting in baldness, lack of grains or empty stalks, so this period should maintain the soil water retention in 70?80%. In areas with a lot of rainfall, attention should be paid to ditch drainage. Trumpet to tasseling period is the harmful period of the corn borer, should be sprayed 500?800 times trichlorfon or insecticide double + Bt powder mixed spraying, control of corn borer.
(2) plowing cultivation: in order to prevent soil crusting, eliminate weeds, improve the growth function of the root system, and promote the root system of more and deeper rooting, the spike period should be according to the soil and weed conditions of plowing, cultivation. Generally, 1?2 times of mid-tillage is carried out before pulling out the male, and 2?4 inch deep mid-tillage is carried out between the rows to cut off some of the hairy roots, stimulate the development of more new roots, and enhance the ability of drought resistance and resistance to fall. Before the male pumping? The big trumpet? period, then shallow plowing 1 time, and cultivate high soil ridge.
3, spiking and fruiting period of management
This period is to determine the number of effective fruit spikes, the number of fruit per spike and grain weight of the key period, at this time, the main grasp of the appropriate amount of supplemental fertilizer (10 kg of urea), drought and flooding, artificial pollination work such as assisted pollination. Spike flowering and grouting should be timely irrigation, keep the soil moist, to meet the plant's water requirements, but irrigation should not be irrigation, to irrigation running water is good. Pay attention to drainage on rainy days, so as to avoid waterlogging and hypoxia root injury. Corn flowering, in case of bad weather, should be artificial pollination 2?3 times, generally in the morning on sunny days 9?11 a.m., can reduce the lack of grain and baldness.
Six, pest control
In principle, prevention is the main, integrated prevention and control, in the management of early detection and early control. Corn diseases are mainly large and small leaf spot disease, rust, blight and so on. Pests are mainly corn borers, stick insects, corn aphids, cotton bollworms, small tigers and so on. Pharmaceutical control, large and small leaf spot disease, rust can be 50% carbendazim 500 times, blight can be 5% wellbutrin 500 times liquid spray. Corn borer, stick insects can be 10% cypermethrin 2000 times plus Bt powder 800 times, corn aphids can be 20% Conforto 3000 times, cotton bollworm can be Bt powder 800 times plus Tianli powder 800 times spray.
VII, harvest
According to different cultivation purposes, the harvest period of corn is different. Fresh sweet glutinous corn full life span of spring and fall planting 80?85 days, summer planting 70?80 days, winter planting 90?100 days. Generally 16?22 days after pollination harvest, summer planting 16 days, winter planting 22 days, after harvesting the fruit should be supplied to the market in a timely manner.