No matter which sowing method, fertilization and fertilization are basically the same in management. With a little management, there will be harvest, but to achieve high yield, we must really master the fertilization technology and skills of rape, supply the nutritional needs of rape at different growth stages in time and scientifically, promote normal growth and development, and lay a solid and effective premise for rape to achieve high yield.
Law of rape fertilizer demand: rape needs more fertilizer and has strong fertilizer tolerance, so the base fertilizer must be applied fully, mainly with high-quality agricultural fertilizer containing more potassium, with nitrogen fertilizer and phosphorus fertilizer.
In the application of nitrogen, phosphorus and potassium fertilizer, the total growth period of rape requires pure nitrogen 1 1~ 12 kg, pure phosphorus 6~6.5 kg and pure potassium 8~ 10 kg per mu. The actual dosage can be calculated according to the types of fertilizers with different nitrogen, phosphorus and potassium contents, and it is important to apply rape with high sensitivity.
Fertilization method of base fertilizer: all agricultural fertilizer, boron fertilizer and phosphate fertilizer containing more potassium are used as base fertilizer, two-thirds of nitrogen fertilizer is used as base fertilizer and one-third is used as topdressing.
Top dressing time:
It is mainly seedling fertilizer, which promotes bolting fertilizer when budding and supplements nutrient fertilizer when bolting and flowering.
Fertilization techniques of rape: ① applying base fertilizer: base fertilizer is the basis of cultivating strong seedlings. If the base fertilizer is insufficient, the nutrition is not comprehensive, the root system of the seedlings is weak, the growth potential is weak, the stress resistance is low, and the seedlings are vulnerable to diseases and insect pests, and the wintering freeze injury increases. Before sowing, apply 4000 kg of farm manure, 40-50 kg of phosphate fertilizer and 0/0-65438 mu of urea/kloc.
(2) Light fertilization and seedling raising: The seedling stage of rape is mainly a combination of thinning and fixed seedling, and intertillage weeding is done well to promote the growth of seedling roots and seedlings. If it is found that leaves turn yellow and weaken, nitrogen fertilizer should be applied in time to promote leaf color change and root growth, so that weak seedlings can become strong seedlings and improve stress resistance. At this time, it is advisable to apply less chemical fertilizer to avoid excessive growth, and it is advisable to apply 5-8 kilograms of urea per mu.
(3) Re-application of bolting fertilizer: The bolting of rape grows rapidly from germination, which is basically a critical period for fertilizer application. From then on, vegetative growth and reproductive growth go hand in hand, and pregnant buds need to branch and bloom, which requires sufficient nutrition to ensure. If the nutrition can't keep up, the nutrient accumulation in the plant is insufficient, the budding branches are few and the pregnant buds are sparse. In order to ensure rich nutrition and inconvenient topdressing at flowering stage, topdressing urea 12~ 15 kg, phosphate fertilizer 20 kg, potassium sulfate 8~ 10 kg, or high nitrogen NPK ternary compound fertilizer 20 ~ 25 thousand can be used this time.
(4) supplementary spraying bolting and flowering fertilizer:
During bolting and flowering, rape consumes a lot of nutrients. In order to prevent late abscission, delay premature senescence, promote pod setting and increase grain weight, 0. 1~0.3% potassium dihydrogen phosphate or other foliar fertilizers can be sprayed on the leaves to promote grain fullness and improve yield and oil yield.
⑤. Bottom application and spraying of highly sensitive boron fertilizer: Rape flowers are very sensitive to boron. When boron is deficient, rape will be stunted, the buds at the top of inflorescence will wither or fall off, and the pod development will stop, resulting in a sharp decline in yield. Therefore, boron fertilizer must be applied before sowing to supplement soil boron for rape growth. When bolting and budding, spraying 0.65 on the leaves.