Corn is one of the most grown field food crops by our farmer friends. Compared with previous years, this year's corn prices are also relatively high, and the corn purchase price on the current market is generally around 1-1.45 yuan / catty. Under the circumstance that grain prices are relatively high this year, if our peasants can seriously plant and manage corn and strive to make it harvest an additional two or three hundred catties per mu of land, this will bring everyone two or three hundred yuan more income.
Then, many people have to ask: how can we increase the yield and income of corn on the basis of not spending more money? Today, the agricultural technology basket will introduce you to how to improve the yield of corn from the scientific and reasonable fertilization and watering of corn. Because, corn has different growth characteristics at different growth stages, and the specific requirements for water fertilizer and effective use in different growth periods are not the same, and many of our farmers and friends usually do not pay attention to this, even if there are two similar corn fields, if anyone can carry out more scientific and reasonable field water and fertilizer management according to the different needs of different growth stages of corn, then whose corn will be able to obtain better growth and obtain higher yield quality.
First, the growth and development of corn is divided into 3 stages, what are the characteristics of the demand for water and fertilizer at different growth stages?
In general, the whole growth period of maize can be divided into three main growth stages, and the demand and demand ratio of three nutrients of maize in these three different growth stages of moisture humidity, nitrogen, phosphorus and potassium are very different, and maize is also very different in terms of growth and development characteristics, field management direction and demand in these three different growth stages. As long as you firmly grasp the contents of the agricultural technology basket to everyone, you know in which direction the high yield of corn should be worked.
The first major growth stage is the seedling stage of maize (pre-growth stage)
The seedling stage mainly refers to the growth stage of maize from seedling emergence to jointing. The water demand of corn at the seedling stage is relatively small, and the water demand at the seedling stage only accounts for about 18-20% of the water demand during the entire growth period of corn; The demand for fertilizer nutrients in maize at the seedling stage is also relatively small, and the demand for the three basic nutrients of nitrogen/phosphorus/potassium at the seedling stage accounts for about 2.5%, 1.1% and 3% of the total nitrogen/phosphorus/potassium demand of maize during the entire growth period, respectively.
The second major growth stage is the panicle stage (mid-growth period) of maize.
The panicle stage mainly refers to the growth stage of maize from jointing to male extraction. The demand for water in maize at the ear stage is relatively large, and the water demand at the panicle stage can account for about 37-38% of the water demand during the entire growth period of maize; Maize has the largest demand for fertilizer nutrients at the panicle stage, and the demand for the three basic nutrients of nitrogen/phosphorus/potassium at the panicle stage can account for about 51%, 63% and 95% of the total nitrogen/phosphorus/potassium demand of maize during the entire growth period, respectively.
The third major growth stage is the flowering stage of maize (late growth stage)
The flowering stage mainly refers to the growth stage of corn from male extraction to maturity. Maize has the greatest demand for water at the flowering stage, and the water demand at the panicle stage at the flowering stage can account for about 43-44% of the water demand during the entire growth period of maize; The demand for fertilizer nutrients in maize at the panicle stage is relatively large (more than the demand at the seedling stage, but less than the demand at the panicle stage), and the demand for the three basic nutrients of nitrogen/phosphorus/potassium at the flowering stage can account for about 46%, 35% and 2% of the total nitrogen/phosphorus/potassium demand of corn during the entire growth period, respectively.
In addition, corn from the specific growth period can also be divided into more detailed, in this agricultural technology basket also give you a brief introduction, in order to facilitate everyone to understand and understand (Note: more than half of the local corn seedlings appear the following characteristics, it means that corn entered the corresponding growth period):
(1) Maize seedling stage (seedling height of about 2 cm); (2) Maize three-leaf stage (the third leaf exposes the leaf center); (3) Maize jointing period (basal stem nodes are 2-3 cm elongated and male panicles begin to elongate); (4) Maize small trumpet mouth stage (female panicle elongation and male spike floret differentiation); (5) Maize large trumpet mouth stage (male panicle panicle axis 0.5-1 cm and female panicle flower differentiation) ;(6) Maize pumping male stage (male panicle tip exposes the leaf top about 3-5 cm) ;(7) Maize flowering stage (male panicle pollen begins to scatter) ;(8) Maize silk stage (female panicle filament extends about 2-3 cm outward from the bracts) ;(9) Maize filling stage (also called corn grain formation stage, the seed of the panicle begins to form and begin to be filled) ;(10) Maize milk ripening stage (the grain in the panicle begins to be rapidly grouted and weight-filling, at this time the grain inside the grain is like a paste) ;(11) Corn wax ripening period (the grain on the panicle is close to the heaviest). , the grain becomes harder); (12) Maize maturity (the grain on the ear of the fruit is sufficiently hard and bright, the milk line inside the corn kernel disappears and a black layer appears at the base of the grain).
Second, the growth characteristics and management priorities of the three different growth stages of maize
Maize in the seedling stage (pre-growth), panicle stage (middle growth) and flower grain stage (late growth) three growth stages, because the growth and development direction of each growth stage is different, so it is necessary for our farmer friends to grasp the key management direction of each growth stage. Among them, the three-leaf stage of the corn seedling stage is the first key turning point of maize growth, the jointing period of maize is the second key turning point of maize growth, and the maize extraction stage is the third key turning point of maize growth.
First, the growth direction and field management focus of maize at the seedling stage (late stage).
When the corn is in the seedling stage growth stage from emergence to jointing, the characteristics of the growth of corn seedlings at this time are that the growth rate of new roots is relatively fast, the growth of aboveground stems and leaves is relatively slow, and the direction of corn growth is mainly based on "rapid rooting and gradual distribution of stems and leaves", so the key direction of our farmers' management in the corn seedling stage should be to "promote seedlings, strong roots, and strong trees".
In general, after sowing corn, it is first necessary to maintain a humidity of not less than 60% in the field, so as to facilitate the germination of corn seeds as soon as possible and ensure the growth of seedlings. Secondly, corn cannot be sown too deeply, because the time for deeply sown corn seeds to germinate will be relatively late, and the corn seedlings that sprout late and emerge late are not as robust as the corn seedlings that sprout early and emerge early. Third, when the corn grows to the 3-leaf stage, it will enter the turning point of nutrient supply (from seed "breastfeeding feeding" to root absorption and growth), when the main nutrients required by the corn seedlings are no longer provided by the seeds (the seed nutrients are exhausted), but rely on the new roots of the seedlings to absorb and supply, at this time, it is necessary to avoid excessive humidity or excessive drought in the field (the corn seedling stage focuses on flood prevention and water accumulation), otherwise it is easy to cause the corn seedlings to die or grow too weakly.
In addition, at this stage of corn from emergence to jointing, it is necessary to ensure that there is sufficient supply of nitrogen fertilizer to promote the growth of seedlings, so if the corn has the problem of weak and slow growth of seedlings during this period, we can apply some nitrogen fertilizers such as urea/ammonium carbon or spray some urea water to promote its vigorous growth.
Second, the growth direction and field management focus of maize at the ear stage (middle stage).
When maize enters the panicle growth stage from jointing to male extraction, at this time, maize will enter the growth stage with the most vigorous growth, the fastest growth rate, the largest demand for water and fertilizer, and the most critical management in the entire growth period. At this growth stage of the ear stage, not only the stem nodes are rapidly elongated and thickened, and the leaves are large and rapidly increased and enlarged, but also the male and female ears of corn will also be vigorously differentiated and rapidly formed.
Therefore, in the maize panicle stage when the stem and leaves are vigorously growing and the male and female ears are vigorously developing, the focus of our farmer friend management at this time should be to strengthen the management of water and fertilizer in the field and ensure that the supply of water and fertilizer nutrients is sufficient, so as to ensure that the corn can quickly increase the fat leaves, promote the formation of a strong and solid stalk of corn, promote the better and more adequate differentiation of corn to form male and female ears, and then lay the material foundation for the next multi-fruit high-quality large fruit ears of corn.
Third, the growth direction and field management focus of maize at the flowering stage (late stage).
When corn enters the growth stage of the ear stage of male to mature, at this time, the plants and stems and leaves of corn begin to stop growing, and the corn will gradually decline and age according to the order of first drawing male ears and then extracting female ears, male flowers scatter powder female flowers pollination, forming stick ears to conceive seeds, filling and increasing weight and maturing, gradually shifting the focus of growth and development to reproductive growth, at the same time, the root system and stems and leaves of corn will gradually decline and age, and the nutrient manufacturing and absorption capacity will gradually deteriorate.
Therefore, during the corn ear stage, the focus of our farmers' field management should be put into ensuring field humidity, increasing the supply of fertilizer nutrients, protecting roots and leaves, promoting the enlargement of stick ears and promoting the increase in grain weight, and preventing crop lodging and premature aging.
Third, the focus of field fertilization management of maize in 33 different growth stages
Under the premise of ensuring the effective water supply in the field (note that corn requires the most water during the extraction period, and ensuring sufficient water supply during the filling period will be more conducive to corn full filling), according to the characteristics of different growth stages of corn, scientific and reasonable fertilization of corn, different proportions of fertilizer in the key period of corn growth "fed" to the "mouth" of corn, which is the simplest and most effective way to enhance corn growth and improve corn yield.
From the perspective of maize fertilizer needs, corn needs to ensure sufficient phosphorus and nitrogen at the seedling stage to promote root and long seedlings, maize needs to supplement nitrogen to promote stems and leaves during the jointing stage, corn has the largest demand for nitrogen fertilizer and potassium fertilizer in the small trumpet mouth stage to the male stage, corn has the largest demand for nitrogen, phosphorus and potassium, the fastest nutrient absorption speed, the best fertilization effect, and the foliar spraying of zinc, boron and potassium dihydrogen phosphate during the growth period of corn can obtain better yield and income increase effects.
In the bottom fertilizer management before corn sowing, the agricultural technology small back basket recommends that everyone use 1500-2500 kg of decomposed farm manure + nitrogen, phosphorus and potassium ternary compound fertilizer of 40-50 kg per mu of land.
In the root topdressing management of corn, if you want to save trouble, then you can concentrate on topdressing once when the corn grows to the big horn mouth stage of 10-12 leaves (nitrogen, phosphorus and potassium compound fertilizer 40-50 kg or urea 30-40 kg), if you want to increase the yield and income of corn topdressing better, then the agricultural technology small back basket recommends that everyone in the corn jointing pregnant panicle stage and the ear grain stage respectively, the first time appropriate more topdressing, the second time appropriately less topdressing.
In the management of foliar topdressing of corn, the small back basket of agricultural technology recommends that everyone spray once with foliar fertilizer once in the jointing stage, horn mouth stage and grain filling stage of corn. During the jointing stage, 50-80 grams of potassium dihydrogen phosphate + 8-10 ml of 0.01% brassicalin endolipid can be sprayed once per mu of land, so as to promote root and leaf, robust growth and stress resistance; During the flared period, 80-120 g of urea + 80-100 g of potassium dihydrogen phosphate + 15-20 g of boric acid + 20-25 g of chelated zinc can be sprayed once per mu of land, so as to promote the growth of strong trees, enhance leaf photosynthesis ability, enhance corn drought resistance/ flood resistance / disease and pest resistance / lodging resistance; During the maize filling period, potassium dihydrogen phosphate + chelated zinc was sprayed once (with progeria plus a handful of urea sprayed together), so as to promote faster and fuller grouting of maize and prevent maize from reducing yield due to premature defertilization or lack of grain at the bald tip.
Note that for corn planting land that lacks zinc in the field, the agricultural technology basket recommends that you must pay attention to the spraying of zinc-containing foliar fertilizer once at the seedling stage and the jointing stage of corn, because the seedling stage and the jointing stage are the stages with the best zinc supplementation effect during the growth period of corn.