Corn multi-ears refers to the phenomenon that there are two (excluding two) or more ears on a single plant of corn, and it is not normal or firm, and it becomes an ineffective panicle.

The phenomenon of multiple spikes (ineffective spikes) occurs frequently in corn production, and some farmers suspect that it is a problem of a certain corn variety. The multi-ear phenomenon has caused different degrees of loss to corn producers, and some farmer's individual fields have even been rejected.

Multi-ear form

(1) Finger spikes. At the same stem section (leaf) in the middle of the corn plant, a plurality of spikelets grow at the same time, which are shaped like fingers, and basically do not seed. People often call it "finger spike", and some people call it "banana ear".

(2) Single pole and multiple ears. In the middle of the corn plant, more than 1 to 2 spikelets were grown at different stem segments (leaves), resulting in multiple ineffective ears on the maize plant.

(3) Multiple poles and multiple ears. Additional plants were planted on the stem segments of the same maize plant, and multiple stems were produced at the stem nodes (leaves) of these tiller plants.

Cause of multiple spikes

(1) Causes of multiple spikes.

The multi-ear is determined by the biological characteristics of corn. In addition to the top 4-6 knots of common corn, there are axillary buds on each stem section, that is, the primordial of the ear, and the axillary buds on the main stem do not stretch will form tillers. The axillary buds on the long knot will differentiate into ears.

Under normal circumstances, only the upper one or two axillary buds can differentiate into the ear, but in the case of excess nutrients, 3 to 5 axillary buds will be stimulated to form a multi-ear phenomenon (some corn varieties, under suitable conditions) Axillary buds will develop into spikes simultaneously, often with 2 to 3 ears per plant, or even more.

In addition, the ear of corn is morphologically a metamorphic lateral stem, the stalk of the ear is a short stalk, and each section has a petal leaf with only a petiole (the leaves), and a certain number of axillary buds are lurking in the locust leafhopper. In the case of the death of the main axis and the accumulation of nutrients, these axillary buds may also germinate and develop into multiple spikelets.

(2) The cause of multiple spikes.

Under normal conditions, corn rarely produces multiple ears, producing multiple ears, which are related to the following factors:

1. Genetic characteristics. Some varieties are susceptible to external environmental conditions and produce multiple spikes. According to reports, hybrid corn is more likely to produce multiple ears than conventional corn.

2. Bad weather. The severe climate that easily leads to multiple spikes is mainly severe drought and low temperature.

Severe drought: The corn is native to the tropics and belongs to short-light crops. If it is severely droughted at the stage of male and female panicle differentiation, the main axis of the ear will stop developing, and the latent buds on the stalk (short stalk) will develop and form a finger. ear". When the "finger ear" is drawn, the tassels are in a loose powder phase, and at this time there is substantially no pollen supply and the fruiting is poor.

Low temperature and low light: The temperature is too low, the rain is continuous, and the light is insufficient, which will lead to insufficient organic nutrition of the corn plants, poor silking of the female silk, or improper germination of the tassels, which may affect the pollination and fertilization, resulting in the first ear not being able to form the ear.

Therefore, the excess nutrients supply the next ear development. If the second ear is still unable to normal pollination, the nutrient supply and the next ear development, even if the ear is normally developed, there is no pollen in the field. Therefore, it is impossible to form a multi-ear phenomenon.

3, big water and big fat.

Big fat and large water are one of the reasons for the formation of multiple spikes in corn. In the stage of differentiation of maize ears, if the water and fertilizer are sufficient, too many nutrient plants can not be consumed, which will cause the multiple axillary buds on the stem nodes to germinate and develop, and there is a possibility of forming multiple ears.

If the rain occurs during the loose powder period, the pollen rupture can not be pollinated normally, and it will also cause multi-filament empty rod phenomenon.

4, pests and diseases.

If corn is damaged by rough disease, the kinetin produced by the virus will break the hormone balance in the plant, leading to the loss of the ear position of the first ear, promoting the germination of other axillary buds and forming many spikelets. The earlier the disease occurs, the more obvious the multi-spot phenomenon. (Analysis of symptoms of early damage to corn rough disease)

In addition, the damage of corn borer, aphids and corn leaf spot will also affect the normal formation of corn ears, resulting in multiple spikes.

5. Improper cultivation and management.

The supply of fertilizer and water in the ear development stage of maize is too high, which promotes the development of multiple ear inflorescences to form multiple ears. The planting density is too large, causing the field to be closed, pollination is poor, the ear can not develop normally, and other axillary buds are matured to form multiple ears.

Multi-earth hazard

The multiple spikes of corn will seriously affect the yield and quality of corn, and some may even lead to harvest.

Prevention of multiple spikes

(1) According to local conditions, select corn varieties that are not prone to multiple spikes. Different regions, different plots, different planting seasons, different light, temperature, water and fertilizer conditions, different varieties, suitable planting areas are also different.

(2) Sowing at the right time and scientifically cultivating. According to the characteristics of corn varieties, local climate, planting season, plots, etc., determine the reasonable sowing period (avoiding adverse weather such as drought, low temperature and low light), sowing amount (reasonable close planting, keeping the plants ventilated and light, and improving light energy utilization) Rate), whether to cover the membrane, etc., so that the light, temperature and water and fertilizer indicators required for each stage of corn are satisfied.

(3) Focus on fertilizer and water management. According to the growth and development rules of corn, master the time of fertilization and the amount of fertilization, apply sufficient base fertilizer, lightly apply seedling fertilizer, and apply fertilizer.

Among them, compound fertilizer is used as base fertilizer, phosphorus and potassium fertilizer is applied early, and nitrogen fertilizer is applied in seedling stage, jointing stage and heading stage respectively. Supply plenty of water during the flowering period to prevent drought. Timely weeding and weeding to keep the soil loose.

(5) Strengthen pest and disease prevention and control. Timely prevention and control of corn mites, mites and corn leaf spot disease, corn rough disease and other hazards, to prevent the emergence of corn multi-ears due to pests and diseases.

(6) Remove the ineffective spikes in time. During the silking period, multi-spot plants should be found. The staff should be actively organized to remove excess ears early. Only 1-2 ears per corn are kept to avoid the consumption of nutrients, promote the normal growth of the ears and reduce losses.