Two common problems in garlic cultivation

In recent years, there are many problems caused by continuous cropping, poor management and unscientific fertilization in Jinxiang, Juye, Cangshan, Zhongmou and Kaifeng, the main producing areas of garlic. It can be summarized in nine words: "yellow leaves, dry tips, dead seedlings, low yield". The author now introduces the causes of the two headache problems in garlic cultivation in recent years to the majority of agrotechnical extension workers and garlic growers.

Problem 1: garlic looked normal years ago, a little yellow leaf dry tip occurred, but after turning green, the garlic seedling seriously yellowed, the yellow leaf dry tip increased rapidly, and the phenomenon of dead trees appeared after rinsing the fertilizer. This phenomenon is most common in the main cultivation areas of garlic, and it has become more and more serious in recent years. There are many reasons for this phenomenon. The main reasons are as follows:

1. In order to save fuel, the quality of rotary tillage is not high, in order to save fuel, the quality of rotary tillage is not high. In order to save fuel, the quality of rotary tillage is not high, and the thickness of rotary tillage is often only more than ten centimeters. Attach importance to chemical fertilizer and despise organic fertilizer, which leads to soil consolidation, acidification and salinization. The suitable soil pH value of garlic is 6.0, and the pH value of acidified soil is often lower than 6.0, which is not conducive to the growth of garlic. In addition, excessive use of chemical fertilizer caused serious damage to soil microbial balance, lack of beneficial bacteria, aggravation of soil-borne diseases and weak stress resistance.

two。 The base fertilizer has too much nitrogen, slightly burns roots, and behaves normally at low temperature before turning green; after turning green, the ground temperature rises rapidly, the ability of damaged roots to absorb water and nutrients is weak, and the injured roots are more stimulated after washing inferior fertilizer, resulting in garlic seedlings yellowing quickly, dry tips aggravating, and heavy dead trees.

3. The insufficient supply of nutrients and over-wet soil during the withdrawal period could lead to the dry tip of yellow leaves of garlic before the year. Around the middle of November, garlic cultivated with plastic film began to withdraw from its mother, during this period, the root system continued to increase and elongate, the aboveground parts continued to differentiate into young leaves, the leaves gradually widened and lengthened, and the nutrition of the seed valve was gradually absorbed. Garlic transition from "heterotrophic growth" to "autotrophic growth". At this time, the root system is short and few, if the lack of nutrient supply or the soil is too wet to cause poor air permeability and weak root absorption of water and nutrients, it will cause the nutrition of garlic "green and yellow", imbalance between supply and demand, and the appearance of yellow leaf dry tip.

4. Suffer from frost injury in winter or late spring cold after a year.

5. Harm to underground pests such as garlic maggots. During the growing period of garlic, it may be damaged by garlic maggots except in winter, especially in years with high temperature, when some garlic farmers apply undermature organic fertilizer, it will lead to a large number of garlic maggots. Garlic maggots eat the pseudostems of garlic plants, causing tissue decay, yellowing of leaves and death of heavy plants.

6. Leaf and stem diseases, such as purple spot, leaf blight, blight, bacterial soft rot and so on.

7. Herbicide damage.

8. If it is dry in spring, it will also cause yellow leaves without watering.

Problem 2: there is no breakthrough in output, and the proportion of garlic is reduced. The author believes that the main causes of this problem are soil problems, seed problems, scientific fertilization, and whether the control of diseases and insect pests (including leaf diseases, soil-borne diseases and underground pests) is effective or not. Of course, the cause of climate is also the biggest aspect, but the climate is not transferred by human will, and cannot be controlled by man. To sum up, the following aspects are the main reasons for the lack of a breakthrough in output and the reduction in the proportion of garlic:

1. Continuous cropping problem: there is no deep ploughing of the soil for many years, the lower part is too hard, the air permeability is poor, and the repeated cropping leads to the aggravation of soil-borne diseases, which will lead to poor root growth. If the roots are not deep and the leaves are not luxuriant, of course the yield will not go up.

two。 Fertilization problems: heavy base fertilizer, light topdressing, excessive use of chemical fertilizer, serious shortage of bio-organic fertilizer or bacterial fertilizer. Because of the high nutrient concentration of chemical fertilizer, the large amount of fertilizer used in successive years, the cost remains high, but it brings a series of damage to the soil, such as soil consolidation, acidification, salinization, pH reduction and so on. At the same time, the root system is poor, the disease is serious, and there is no breakthrough in yield.

3. There is a serious lack of medium and trace elements.

4. The use of a large number of available fertilizers on the base fertilizer has the advantages of low utilization rate, serious loss and leaching, and early senescence in the later stage, which affects the yield. Because the seedling stage does not need much nutrients, the quick release of available fertilizer years ago also led to the green and prosperous growth of garlic seedlings, inadequate preparation for entering the cold winter, once the cold current comes, there is no doubt that it will freeze. Before overwintering, it is most ideal for seedlings to grow to 5 leaves, 1 heart to 6 leaves.