Does high summer heat cause poor pollination in corn? Leaf curling and head smut control measures

In the process of growing corn, various problems always arise, so if we want to ensure a high corn yield, we must pay close attention to the growth of the corn. So does high summer heat cause poor pollination in corn? What are the control measures for corn leaf curling and head smut?

I. Does high summer heat cause poor pollination in corn?

As for whether high-temperature weather affects corn pollination, I believe many friends know the answer and have more or less encountered such a situation, especially in summer corn planting areas, where the pollination period happens to fall during the dog days (in most areas). If it is around noon, the temperature can exceed 35 degrees (and in some areas can even reach 40 degrees), and when corn pollinates under such high-temperature conditions, it will be affected to some extent.

Corn pollen is on the tassel at the top of the plant. When the pollination period arrives, it falls off automatically, and then part of it lands on the ear of corn, and finally it grows into a corn cob.

When the temperature is higher than 35 degrees (or even higher), it is not conducive to pollen formation. For example, the tassel cannot flower, which blocks pollen shedding, or the development of the ear is blocked and becomes abnormal, delaying silking of the ear. Under such circumstances, poor pollination occurs, resulting in either no kernels or shriveled kernels.

When high temperature lasts too long, the pollination period may be shortened. In that case, the situation of no cob formation will increase, and the impact on the final yield is still quite large.

When high-temperature weather occurs during corn pollination, what should we do?

For particularly severely affected plots, artificial supplementary pollination measures can be adopted. There are 2 methods:

1. Collect pollen manually, then put it in a container and sprinkle it on the ears that have been poorly pollinated. However, when doing this, you need to pay attention: first, sprinkle lightly; second, choose the morning, avoid rainy days, and carry out artificial pollination in windless weather. However, the workload is very heavy. It is fine for small plots, but for farms, cooperatives, and large-scale growers, it is not very suitable because the labor burden is too heavy.

2. Directly shake the corn plants to let the pollen fall for pollination. A rope can be used to help, but also note that the shaking amplitude should not be too large, and then, as above, choose the morning and windless, rainless weather to carry it out.

In addition, some friends have also reported that when the field temperature is too high, irrigation can be used to lower the temperature and reduce the problem in the field. This method can also be tried, and it can also alleviate part of the drought. However, the issue of easy lodging must also be taken into consideration.

II. What are the control measures for corn leaf curling and head smut?

1. Corn leaf curling

Some varieties are more sensitive to climate change. If there is alternating dry and wet conditions formed by drought and rainfall, or alternating cold and hot conditions formed by high temperature and relatively low temperature, corn leaves will curl. This kind of curling generally occurs from the large trumpet stage to the tasseling stage.

This situation mainly occurs in individual varieties. In mild cases, only the top leaves curl and bend slightly to the side. In severe cases, when bending to the side, the top leaves almost touch the ground, forming an arch shape, while the plant remains completely upright, and the tassel begins to shed pollen normally and the ear begins to silk normally, without affecting normal flowering and pollination. In addition, some varieties are more sensitive to climate due to genetic reasons, and sometimes also show brief leaf twisting and side bending. This situation generally unfolds naturally within a week and also does not affect normal flowering and pollination, so there is no need to worry.

2. Head smut

Preventive measures:

① Choose varieties resistant to head smut.

② Sow late at the appropriate time.

③ The main source of pathogens in the soil is still that diseased plants in the field were not cleaned up in time, and were not cleaned up before the pathogens matured.

④ Manure carrying pathogens means that the cattle, sheep, and other livestock we raise eat plants carrying head smut pathogens. The pathogens survive after passing through the digestive tract, and finally return to the field with the manure. Therefore, diseased plants must be deeply buried or burned, and must never be fed to cattle, sheep, and other livestock.

⑤ Be sure to choose coated seeds, and be sure to choose seeds with high-quality coating.