How to distinguish the big trumpet stage and the small trumpet stage of maize seed production?

In production, bell-shaped period is often used as a sign of maize growth process and field fertilizer and water management. ?

The trumpet stage of maize means that the plant has 12- 13 visible leaves and 7 spreading leaves, and the heart leaves are trumpet-shaped. Big trumpet stage means that most of the leaves are visible, but not fully developed, and the heart leaves are clustered, flat and hollow, shaped like a big trumpet; Big horn stage (leaf age index is 55%-60%,11-0/2 leaves spread), the big horn stage of maize is from jointing stage to heading stage, which is the stage of simultaneous vegetative growth and reproductive growth. The growth of roots, stems and leaves is very vigorous, the volume expands rapidly, and the dry weight increases sharply.

Extended data:

Superficial application

The big trumpet stage is the period when corn needs fertilizer most and the fertilizer intensity is the greatest in its life. At this stage, top dressing should be strengthened to prevent fertilizer loss. Fertilization should be widely carried out according to soil fertility and seedling conditions, with 30-35 kg urea per mu, which should be applied after deep digging and covered with soil after fertilization. Corn fields with good growth can be applied less or moderately slowly; On the contrary, it should be applied more and applied in advance; If the growth is too poor, potassium dihydrogen phosphate or high-efficiency concentrated humic acid liquid fertilizer 120- 150g 2-3 times per mu should be applied, and sprayed every 5-7 days/time, with obvious effect.

2. Tillage and soil cultivation

There is a strong demand for nutrition, water, light and oxygen at the big horn stage of maize. Intertillage can loosen soil, improve ventilation and water and fertilizer supply, thicken soil layer at the base of plants, promote root growth and prevent plants from lodging. At the same time, it can remove weeds and save water and moisture. Therefore, intertillage is an important measure for the management of corn in the big trumpet period. It is not advisable to raise the soil too early in the big bell mouth period, and the height of raising the soil is 6- 10 cm. After cultivating the soil, spray water with corn bran or ethyl tamoxifen per mu. It is required to spray evenly without leakage. If it rains within 8 hours after spraying, reduce the dosage and spray again as appropriate.

water

The big horn period of corn is in the high temperature season, and the water demand and evaporation of plant growth are increasing day by day, which is the key period of corn water demand. Generally, the small bell mouth period and the large bell mouth period should be watered separately, and the small bell mouth period should have a small amount of water, which can be ditched alternately, and the large bell mouth period should have sufficient water. At the same time, we should always pay attention to the weather, so that waterlogging can be discharged and drought can be watered.

4. Pest control

During this period, corn borer, armyworm, cotton bollworm and leaf spot will occur to varying degrees, so it is necessary to investigate the occurrence of pests and diseases in the field at any time. If there are pests, it is best to wash the heart with toxic soil made of phoxim or diphacinone. In case of diseases, apply 600 times of Antaisheng or bactericide solution +300 times of potassium dihydrogen phosphate or other foliar fertilizers for foliar spraying, and spray the liquid evenly.

References:

Field management methods to ensure high and stable yield of maize