Why are corn seedlings of different sizes on the same piece of land and of the same variety? How to prevent and cure it?

Before and after the Qingming Festival, plant melons and beans. After a while, it's time to plant corn, and careful farmers may notice that corn seedlings sometimes grow large and small after the emergence of corn every year. The productivity of corn per plant is high, and the yield is reduced by 150-300 grams without one plant. It is often said that "there is a shortage of a seedling in spring and a jin of grain in autumn". If there is a lack of seedlings, the yield will be reduced by 60-80 kg per mu. Therefore, ensuring the whole seedling is the premise of high yield of corn.

So why do corn seedlings grow in different sizes when sowing on the same piece of land and the same variety at the same time? The emergence of large and small seedlings of corn will affect the yield in the later stage, so try to avoid this situation and keep these aspects in mind!

1. Uneven soil moisture

When the weather is dry, it will cause uneven soil moisture. In this way, in places with better soil moisture, corn seedlings will emerge early, and in places with poor soil moisture, corn seedlings will emerge late, and sooner or later will lead to uneven growth of large and small seedlings, so when sowing, we must pay attention to soil moisture and make plans in advance.

Second, the depth of sowing is different

If the quality of soil preparation is poor, the soil will be uneven, and when mechanical sowing is used, the high places will sow deep, and the low places will sow shallow; in addition, if there are more crops in the field, they will be affected by mechanical sowing. It will lead to different depths of sowing. In the case of good soil moisture, the seedlings with deep sowing emerge late, and those with shallow sowing emerge early; in dry weather, those with deep sowing emerge early, and those with shallow sowing emerge late, which leads to the formation of large and small seedlings.

Third, the seeds are not graded or damaged

The quality of corn seed will also affect the emergence of corn, some corn seeds are not graded and selected, and the seed size is inconsistent, which will also lead to strong seedlings of large seeds and weak seedlings of small seeds, which will appear large and small seedlings from the seedling stage.

The seeds are damaged. The damaged seeds are easy to be infected with bacteria, grow and develop slowly, and easily grow into weak seedlings, resulting in large and small seedlings in the field.

Therefore, when buying seeds, we must observe the evenness of seeds and the damage rate of seeds, so as to prevent the large and small seedlings of corn from buying seeds.

4. the time of setting seedlings has been postponed.

After the emergence of maize seedlings, suitable time seedlings, fixed seedlings can avoid seedling crowding, compete with each other for glory, fertilizer and water, in order to cultivate strong seedlings. The interseedling work is generally carried out in the 3-4 leaf stage, because the maize is in the "weaning period" around the 3-leaf stage, which requires good light conditions, which is conducive to the production of more nutrients and supply the growth needs of seedlings.

If the plants are overcrowded and the roots are staggered in the seedling stage, there will be a competition for water and fertilizer. Moreover, the leaves of seedlings overlap with each other, which not only affects photosynthesis, but also prone to "seedling shortage". Seedling setting is usually carried out at 4-6 leaves. If the seedlings can not be carried out on schedule, the areas with more seedlings will form thin, weak and high seedlings, and finally large and small seedlings will appear. So how to prevent the emergence of corn seedlings?

The main results are as follows: 1. Select the improved varieties with high purity and high germination rate, grade the seeds, sow the seeds with full and uniform large seeds, and mix the seeds with chemicals.

2. Strictly control the sowing quality of the soil preparation, realize the high-standard operation, and ensure the whole seedling and the whole seedling in one sowing.

3. Sowing at the right time. If it is too late to water the soil moisture at the bottom when sowing, the watering head water after sowing requires shallow irrigation and irrigation evenly, which is an important measure to protect seedlings in arid areas.

4. Suppress after sowing. After sowing, if the soil gap is large, the seed is not easy to absorb water, which affects the whole maize seedling, and the suppression after sowing can increase the contact between the seed and the soil, strengthen the seed absorption of soil moisture, increase the moisture content of the lower soil and increase the moisture content of the sowing layer. to facilitate the emergence of seeds.

5. Prevent and control the harm of insects, birds and animals. After emergence, it is necessary to control underground pests in time so as not to cause lack of seedlings. 6. if it is found that there is a lack of seedlings and broken ridges, it is necessary to check the seedlings for replanting or transplanting in time.

7. if seed fertilizer is applied, seed fertilizer should be separated, and burning seeds and seedlings should be strictly prevented.

8. If the rainfall is large before emergence after sowing, when the ground is hardened, shallow ploughing should be carried out in time to cut through the hard crust of the surface, which can help the seedlings to be unearthed. But don't damage the buds when you loosen the soil.