The lack of boron in vegetables often leads to the phenomenon of "flowers without fruit", the most typical of which is rape. Boron fertilizer is an indispensable trace element in rape. Generally, when the available boron content in soil is less than 0.3 mg/kg, boron deficiency symptoms are easy to occur, resulting in large-scale production reduction. However, the effective application of boron fertilizer will provide a lot of effects on the yield increase of rapeseed, so many farmers and friends are using boron fertilizer, but the misunderstanding must be well understood in order to apply boron fertilizer well.

Myth 1: Boron fertilizer can increase yield, and it is believed that the more boron fertilizer applied to rape, the better.

As we all know, boron fertilizer is a trace element, not a large number of elements such as nitrogen, phosphorus and potassium. The amount of boron fertilizer needed for rape growth and development is not much, but it is also essential. Therefore, the dosage should be strictly controlled. Appropriate amount can promote the growth and development of rape, but excessive amount will seriously inhibit the seed development and root growth of rape and reduce its stress resistance, which will have a more serious impact when fertilizer is damaged. Generally speaking, the dosage of boron fertilizer is 0.5- 1 kg per mu, and the concentration of spraying fertilizer is 0.2%-0.4%.

Myth 2: Boron fertilizer can promote flowering, and it is considered that applying boron fertilizer at flowering stage has the best effect.

In fact, this statement is not accurate Boron fertilizer is not only effective at flowering stage, but also exists at all stages. Generally speaking, spraying boron fertilizer at seedling stage and bud stage has the best effect. The application of boron fertilizer in seedling stage is embodied in base fertilizer and foliar boron fertilizer, which can stimulate root growth. Spraying boron in bud stage can promote flower bud differentiation and stem elongation. The most important function is to ensure the photosynthetic efficiency of leaves and improve the yield-increasing effect. So in this way, the application of boron fertilizer at flowering stage is really late.

Myth 3: Boron fertilizer is widely available, and it is believed that as long as there is boron fertilizer, it will have an effect.

There are many kinds of boron fertilizers in the general market. Although some inferior boron fertilizers have the word "boron fertilizer", the net content is only a few tenths of a percent, or even none, so spraying has no effect at all. Compared with those high-quality boron fertilizers, it has high purity, good fertilizer efficiency and easy absorption, which saves a lot of trouble. Therefore, when buying, you need to go to a regular agricultural store to ask clearly.

In addition, the application method of boron fertilizer is nothing more than basic fertilizer application, foliar spraying fertilizer, mixed irrigation application and so on. There are borax and boric acid. Fertilization period is mainly from seedling stage to flowering stage, and it is used in sunny days.

Application of base fertilizer (suitable for land with serious boron deficiency): Before sowing or transplanting rape, apply about 0.5 kg of borax mixed soil or organic fertilizer near the root system of sowing area, transplanting area and hole, but try to avoid direct contact between seeds and root system, and carry out soil testing and fertilization if possible.

Foliar spraying: the period of spraying fertilizer should be sooner rather than later, and it is best to spray it once in the late seedling stage and bud stage of rape, with the concentration of 0. 1%-0.3% boron fertilizer water solution. Try to choose sunny evening or morning, when the stomatal opening is large. If it rains 1-2 days after spraying, spray it again.

Mixed application: boron fertilizer can also be mixed with compound fertilizer and organic fertilizer. In the growing period, it can be used as base fertilizer or topdressing combined with irrigation, and the effect is good.

To sum up, to avoid the above misunderstanding, we must follow a principle: the upper limit of boron application is seriously lacking, and the lower limit is normally needed. That is, the use of boron fertilizer in normal plots is based on the minimum amount of boron fertilizer, with topdressing as the main factor and base fertilizer as the supplement; However, in the low boron-deficient production areas, the highest boron fertilizer is the main fertilizer, and basic fertilizer is needed to raise the land, supplemented by topdressing.