Reasonable planting density of the latest Maize

Corn planting density is one of the factors that directly affect corn yield. Practice has proved that corn yield increases with the increase of density in a certain range, but when the density reaches a certain value, the increase of density will make the yield decrease, so the appropriate density is the factor that determines the yield.

1. Adapt to local conditions. Select varieties suitable for local planting density, as improved varieties under different conditions also has its relativity, only according to local climatic conditions, geographical conditions, water and fertilizer conditions to select varieties suitable for dense planting.

2. Variety characteristics. Different types of varieties have different density tolerance, compact hybrid has strong density tolerance, yield is stable when density increases, suitable planting density is larger, flat type has poor density tolerance, density increase range is small, if density increases, yield will be reduced.

(1) flat-type mid-late maturing maize hybrids. This variety has high plant height, wide leaves and many leaves. The average angle between leaves above ear position and main stem is more than 35 degrees, and the average angle between leaves above ear position and main stem is more than 45 degrees. It is suitable to keep 3000~3500 seedlings per mu, suitable for spring sowing, which can make full use of light and heat resources to increase effective accumulation and improve yield.

(2) early-maturing and density-tolerant maize hybrids with vertical leaves. The plant type of this variety is compact, the leaves are upward, the angle between each leaf above ear position and main stem is less than 25 degrees on average, and the angle between each leaf below ear position and main stem is less than 45 degrees on average. The density of seedlings per mu is 4500~5000. Suitable for sowing after harvest.

③ Intermediate type. The angle between leaf and main stem of these varieties is between compact type and flat type, most of them belong to middle early maturity and density tolerance varieties, the density of seedlings per mu is between 3500~4500, suitable for wheat ridge interplanting or rape stubble sowing.

3. Choose reasonable density according to variety characteristics, yield level, soil fertility and fertilizer level.

① In the middle yield field of 400~500 kg/mu, the suitable density of flat-type maize hybrid is about 3000 plants/mu, and that of compact hybrid is about 4000 plants/mu.

(2) The suitable density range of yield level of 500~600 kg/mu is: about 3500 plants per mu for flat-leaf maize hybrids, about 3700~4000 plants per mu for compact mid-late maturing large-ear hybrids, and about 4500 plants per mu for compact vertical-leaf mid-ear hybrids.

(3) The suitable density range of yield level above 650 kg/mu is: compact medium panicle type, 5000~5500 plants/mu, compact large panicle type, 4500~5000 plants/mu.

4. Densification and production increasing technology. According to the characteristics and production conditions of maize varieties, the planting density of existing density-tolerant varieties will be increased by 500~600 plants/mu according to local conditions, provided that density-tolerant varieties and plots with good water and fertilizer conditions are selected.

5. The ear number per mu of corn is one of the three elements that constitute corn yield. The density directly determines the yield of corn. Due to many factors that limit the final ear of corn in nature (such as diseases and insect pests, nutrient light, etc.), the ear rate of planting density is generally 90%~95%. In order to ensure that the ear number per mu reaches the set target, the number of ears in the field should be increased by 5%~ 10%, so as to achieve the expected ear number index.