Growth characteristics and Management Countermeasures of garlic in April

The growth of this period is the combination of vegetative growth and reproductive growth, and the early stage is dominated by the rapid growth of vegetative body. with the large growth space and accelerated growth of garlic, the vegetative growth of garlic has been fully developed. the number of leaves, the assimilation area of leaves and the number of roots reached the maximum in a lifetime. Garlic bolts grew mainly after the middle stage, and the bulbs were in the early stage of expansion. by the end of this period, the total root number could reach 120-150, the depth of penetration could reach 40-50 cm, and all the leaves of the plant were formed.

In this period, the growth of all parts of the plant is the largest, and sufficient water and fertilizer are needed to lay the material foundation for high yield and high quality. this period is also the most urgent period for fertilizer and water, and there are two periods of maximum efficiency for fertilizer. That is, the nutritious growth period (early April) is the period of maximum nitrogen fertilizer efficiency. The effect of applying nitrogen fertilizer in this period was the highest in the whole life, and the nitrogen deficiency had the greatest effect on the yield, and the earlier the nitrogen deficiency, the greater the effect on the yield. The bolting extension period of garlic (late April) is the maximum efficiency period of potash fertilizer. the results show that the response of garlic to potash fertilizer is that potassium deficiency has a great effect on yield in the later growth stage, and the later the effect is, the greater the effect is. At the same time, it was reported that there was a significant positive correlation between garlic maximum leaf width, pseudostem diameter (leaf sheath) and garlic bolting and garlic head weight. In order to obtain high yield of garlic and garlic bolts, it is necessary to cultivate plants with thick leaf sheaths and broad leaves, which is also the peak period of garlic diseases and insect pests.

The following management should be done well in production:

Re-application of seedling fertilizer

In the first ten days of April, topdressing with nitrogen and sulfur should be combined with watering to improve soil fertilizer supply and accelerate the ability of root system to absorb fertilizer, so as to meet the nutrient requirements of exuberant growth of garlic. 40% nitrogen and sulfur fertilizer can be applied to 70kg / mu, which can be sprinkled or flushed. At the same time, it is proved that the effect of applying nitrogen and sulfur fertilizer in this period is better than that of urea.

Prevent ground maggots and garlic mites

The damage of garlic maggot larvae has occurred in early April, so it is necessary to combine watering and irrigation to control both garlic mites and nematodes. The effective drugs are phoxim and its mixture or chlorpyrifos plus chlorpyrifos, which has a good effect on killing maggots and mites. The use of highly toxic and residual pesticides is prohibited in order to ensure the food safety of garlic bolts and garlic heads from the source.

To prevent the apprentice from growing strong:

With the increase of air temperature and the sufficient supply of fertilizer and water, the growth rate of garlic plant is obviously accelerated, and it is easy to grow, which makes the garlic plant taller and the leaf sheath thinner. At this time, garlic nutrition agent should be sprayed in time to increase the thickening agent of garlic leaf sheath, so as to coordinate the relationship between vegetative growth and product organ growth, and restrain the excessive growth of vegetative body. In order to meet the requirements of high yield of garlic for plant type, to achieve the management purpose of thick leaf sheath and wide leaves, and to lay a material foundation for the full growth of garlic head.

Strengthen the prevention and control of white rot

Garlic white rot mostly broke out 3-5 days after Qingming Festival watering. According to the study, in order to reduce the occurrence of white rot, the best control period should be spraying fungicide 2-3 days after watering to enhance plant disease resistance and inhibit pathogen activity, so as to achieve twice the control effect. According to the experiment, the more effective drug to control garlic white rot is Baihujing (author compound) 90 grams per mu, followed by prohydantoin, 100g / mu and 150g / mu.

Prevent leaf blight

Garlic leaf blight is the main disease of garlic leaves, which occurs from the middle of April to the first ten days of May, and the peak period is in the period of the most vigorous growth of garlic (late April). There are four main types of garlic leaf blight in the field. These four types will form dry blight spots on the leaf surface, and the control drugs are Baifujing, prohydantoin and so on, but the effect of Baifujing is better. Drug control should be started in the middle of April. It must be prevented once before watering the bulging head, and then be used continuously for 2 or 3 times according to the weather conditions.

Apply good head-expanding fertilizer

In late April (mostly around "Grain Rain"), 30% (14-0-16) sulfur-containing and high-potassium compound fertilizer can be applied with water to accelerate the expansion of garlic. At this time, the root system has gradually tended to senescence, the production should be based on root cultivation and root protection as the starting point, strictly prevent root injury affecting yield, watering and fertilization time should not be later than 5 days before the harvest of garlic bolts.