The top of the corn ear, the seed granules or the unrooted kernels, called bald tops, also known as "difficult to sharpen", is a common phenomenon in corn production, which generally leads to a 5% to 10% reduction in corn production, and even more than 30%. . Therefore, effective measures should be taken in production to reduce and prevent the occurrence of baldness. Corn baldness The main reasons for the baldness of corn are as follows: Genetic characteristics of the variety. Order popcorn wire drawn from different bracts, filaments out of the top of the latest, to coincide with insufficient field pollen or shedding if the top end of the filament withdrawn, easily lead to poor pollination top filaments, forming bald. Rainy weather. Corn loose powder, if you encounter rain and other natural disasters, can not easily lead normal corn tassel loose powder, Ear silking poor, even spinning, filament easy leggy, aging, it can also cause baldness corn. Drought and water shortage. Corn life requires a lot of moisture. According to research, the greater the soil moisture, the smaller the chance of corn being bald. In particular, when drought occurs during the tasseling period, pollen viability will be weakened or even lost. After the filament is delayed or extracted, it is easy to lose vitality and shorten its life span, resulting in a decrease in seed set rate and formation of baldness and even empty poles. The density is not reasonable. Corn is a high-stalk crop that requires adequate lighting and ventilation. If the density is too large, it may cause the individual's nutritional dysplasia, the field is closed, and the permeability is poor, so that the top grain of the ear does not get enough nutrients, and some pollen is difficult to fall on the stigma during pollination, forming baldness. Lack of nutrition. When the corn is late in growth, the grain stops growing in the middle of the growth, and the top of the ear increases and becomes bald. Zinc deficiency in corn is commonly known as “flower white seedlingsâ€, that is, there are pale yellow or white streaks between the veins, the stems are weak, the males are slender, the silking is delayed, the ear is poorly developed, and bald or thin rods are formed. Pests and diseases. The pests and diseases that cause the baldness and grain loss in corn are mainly large and small spotted diseases and corn borer. Especially the tops of tassels and ears are vulnerable to corn mash, causing insufficient powder source and filiform damage, thus forming bald granules. Prevention For the baldness of corn, the following control measures can be taken: Choose a good variety. There are three types of corn: compact, semi-compact and flat. It should be combined with local natural conditions and planting system, and the appropriate variety types should be selected to maximize the yield increase of fine varieties. Sowing at the right time. Corn is warm, not resistant to low temperatures, and requires a relatively high temperature during the entire growth period. If the seeding is too early, the emergence period is long, the emergence rate is low, the seedling is weak, and the physiological disease is serious; when the planting is too late, it affects the late corn filling, which leads to late maturity. Spring corn is generally suitable for planting at a temperature of 5 cm above 12 °C, and summer corn is no later than the end of June. Check seedlings to replant. After the emergence of corn, timely seedling replanting can be re-bred along the wind direction at the edge of the plot to ensure that the top pollen of the ear is not missed. Practice has proved that, after taking the measure bald rate of 3% to 5% or less, while the average rate bald plots up to 10% to 15%. Reasonable close planting. Appropriate increase of planting density is one of the measures to increase corn yield. The density can be determined according to climatic factors, irrigation conditions, soil fertility and variety types, so that individuals in the group can receive light, ventilate and transmit light, increase corn seed setting rate and reduce Bald. Generally, 3000 to 4000 plants per mu are suitable. Rational fertilization. On the basis of the application of the base fertilizer, based on the principle of light, medium and heavy, and after the seedlings, apply appropriate amount of compound fertilizer to promote the vegetative growth of corn; apply high-nitrogen compound fertilizer in the big bell period to ensure the reproduction at the end of the season. Growth does not de-fertilize; from the heading to the filling stage, proper root dressing is carried out. In fertilization, attention should be paid to the application of zinc fertilizer to promote grain fullness and reduce baldness. Interlaced to help the pollination. When the tassel has just extracted the top leaves and has not been loosened, it will be separated or detached, reducing the water and nutrient consumption of the plants, improving the ventilation and light transmission conditions of the upper part of the corn, improving the photosynthetic efficiency, reducing the damage of the corn mash, promoting the large grains and the fullness of the seeds. It is not advisable to go to the male, especially the 4 to 5 rows around the cornfield should not go to the male, so as not to affect the pollination and cause empty spikes. At the same time, continuous artificial pollination of 2 to 3 times during the silking of the ear can significantly increase the seed setting rate of the corn. Prevent disease and cure insects. Prevention and treatment of large and small leaf spot disease can be controlled in the early stage of the disease with carbendazim, bacteriostatic or powder rust. The control corn borer can be applied to the heart leaf and leaf axils by mixing zinc sulphur or carbofuran into the poisonous sand during the big bell period. YT-H711 YT-H711 Shenzhen Sunshine Technology Co.,Ltd , https://www.yatwin.com
Causes and control measures of corn baldness