The application of boron fertilizer can promote the increase of rapeseed, especially the application of boron fertilizer in the soil with serious boron deficiency, and the yield increase is more remarkable. The practice of many years has proved that the increase is 20%, and the increase is more than 30%. The application methods of the boron fertilizer include base application, foliar application, pouring, seed treatment and compound application. Currently, boron fertilizers sold in various places mainly include borax and boric acid, but mainly borax.
The application of boron fertilizer into the soil before sowing or transplanting rapeseed can supply the whole growth and development needs of the crop, which is beneficial to meet the needs of boron in the whole growth period of rapeseed, long-term fertilizer effect, and saving labor, in the soil of severe boron deficiency, The effect of increasing production is particularly significant. Use 0.5 to 1 kg of borax per acre and mix with 15 kg of dry fine soil or organic fertilizer and chemical fertilizer as the base fertilizer to open the ditch or apply. At the time of application, since boron has an inhibitory effect on seed germination and radicle growth, direct contact of the boron fertilizer with the seed should be avoided. It is not advisable to deepen or apply boron fertilizer.
The boron fertilizer is mixed with human and animal manure or fertilizer aqueous solution, and is poured into the seeding hole as the base fertilizer during sowing or poured into the rapeseed seedlings in the early and middle stages of rapeseed for topdressing. The effect of applying boron fertilizer is better than that of dry application or leaf. The effect of surface spraying is better.
Soak seeds with 0.1% borax solution for 6 hours or 1 kg seeds with 4 grams of borax. However, since boron has an inhibitory effect on seed germination, it is prudent to use boron fertilizer for seed soaking, and it is generally not suitable for use. In addition, when transplanting rapeseed, the rooting with 0.1% boron-containing aqueous solution has a certain yield increasing effect. The above two methods have the characteristics of strict technical requirements, inconvenient operation, and labor-intensive, so they are rarely used in production.
Foliar application of foliar spray has the characteristics of fertilizer saving, fast crop absorption and flexible application period. The period of foliar application should be sooner rather than later. The effect of spraying boron fertilizer on the leaf surface after rapeseed is not significant. A 0.1% to 0.3% aqueous solution of boron fertilizer should be sprayed at the end of the seedling stage (before and after flower bud differentiation) and during the twitching period (15 to 30 cm high), which is a critical period for spraying boron. If borax is used, it is first dissolved in warm water at 40 ° C and diluted with water. If you use Speedo Boron, it can be quickly dissolved at any temperature. The dosage is such that the spray is uniform and the leaves are sufficiently wetted with water droplets. Generally, about 50 kg of fertilizer solution per mu is used in the seedling stage, and about 80 to 100 kg in the later stage. Spraying boron should be done in the evening or in the morning. Because the relative humidity is large at this time, the opening of the pores is beneficial to the absorption of rapeseed into the body. It should not be sprayed during dry and high winds. Spraying should be re-sprayed within 36 hours after spraying. Although foliar spray has a significant yield-increasing effect, in areas with severe boron deficiency or soil, such as less spraying times, boron is often unable to ensure the requirement of boron in rape in time, so the spraying effect is lower than that of basic boron fertilizer. .
Combined with the application of boron fertilizer and organic fertilizer and nitrogen and phosphorus fertilizers, the synergistic potential of fertilization can be exerted. Apply 1000-2000 kg of high-quality farmyard manure per mu to base fertilizer. In medium and low-yield soil, the application of nitrogen fertilizer is 0.5 kg per mu, and the appropriate amount of nitrogen fertilizer is 12.5-17.5 kg [nitrogen-boron fertilizer ratio (25-35):1]; the suitable amount of phosphate fertilizer is 6 kg (phosphorus). The ratio of boron fertilizer is 12:1).
The appropriate amount of boron fertilizer depends on the type of soil and the condition of boron deficiency. Generally speaking, the upper limit of boron fertilizer should be applied to the land with serious boron deficiency in sandy soil, and the lower limit of boron fertilizer should be applied to the land with less boron deficiency.