What is the reason for the lack of seedlings and the death of seedlings in field corn? Urgent! ! ! !

1, too high or too low soil moisture can easily lead to lack of ponds and seedlings. Too much soil moisture during sowing or rain after sowing leads to too much soil moisture, which causes seeds to swell and rot, leading to lack of seedlings and broken ridges; The soil moisture is too low to meet the water needed for seed germination, which leads to seed rot and poor field emergence.

2. The soil temperature is very low. Because of the continuous low temperature weather after sowing or sowing, the seed vigor is low, the germination is slow, and the soil is left for a long time, which is easy to cause seed rot, lack of seedlings and broken ridges; In addition, when corn is sown at low temperature of 10- 15, the soil moisture is large, which makes the seeds absorb the low temperature moisture in a short time, causing imbibition and chilling injury, which leads to the failure of normal germination and seedling formation. Normal seeds can not germinate even under suitable conditions after imbibition and chilling injury.

3. There is insufficient oxygen in the soil. Too deep sowing, too high soil moisture or hardening, poor soil permeability, insufficient oxygen affect seed metabolism, and poor seed germination leads to lack of seedlings.

4. The quality of soil preparation is poor, there are many clods in the ground, and there are many residual films, straws and weeds, which affect the emergence of seeds.

5, pests and diseases cause dead seedlings, and underground pests such as cutworms, white grubs, white grubs, and needle worms harm corn seedlings, resulting in dead seedlings and lack of basic seedlings in the field; The main disease of maize seedling is maize seedling blight, and its symptoms are as follows: most maize seedlings begin to get sick at the 2-3 leaf stage, the leaves of diseased seedlings turn yellow, the edges are scorched, and the leaves gradually dry up from bottom to top. When the seedlings were pulled out, the root system was stunted, the root hair decreased and the root system was brown.

6, the rational use of chemical fertilizers and pesticides, to prevent chemical fertilizers from burning seedlings or phytotoxicity.

7. After seed coating, it should be dried for sowing. At the same time, it should be noted that seeds with germination rate as low as 95% should not be planted singly, otherwise, once the germination conditions are not suitable, it will inevitably lead to different degrees of seedling shortage.