Rape cultivation: what is rape "flowering but not fruitful"?

What is rape "flower but not solid"? Is there any way to prevent it? Please introduce rape "flower but not solid", also known as atrophy not solid. That is, from the onset of the disease to maturity, the plant still flowers one after another, but it cannot bear fruit normally. The main cause is a physiological disease caused by planting rape in boron-deficient soil. It mainly occurs in cabbage varieties, but it has also been found in cabbage in recent years. After the disease, the yield is generally reduced by 2~ 30%, and serious harvest is even rare, which is a problem worthy of attention in rape production. The role of boron on rape: rape is a crop that needs more boron. Boron can promote the germination of pollen, so that pollen tubes quickly enter the ovary, which is conducive to the formation of seeds. The most obvious characteristic of boron deficiency is "flower but not fruit". When boron is seriously deficient, rape can be diseased at seedling and bolting stage, and the diseased plants will wither and die. Boron deficiency is moderate or slight, and the disease occurs after flowering, and the diseased plants cannot set seeds normally. Boron fertilizer can effectively prevent rape from "flower but not fruit". After experiment, double low rape planted in boron deficient area can increase yield by 10%~20% by applying boron. Compared with Zhongyou 821, the double low rape has stronger ability of absorbing boron and higher boron requirement. When the water-soluble boron in soil is lower than 0.5PPm, the boron deficiency symptoms will appear in different degrees and the yield will be seriously reduced. When the water-soluble boron reaches or slightly exceeds 0.7PPm, the yield will be significantly increased. Introduction of boron fertilizer: boron fertilizer belongs to a trace amount of efficient fertilizer. Compared with nitrogen, phosphorus and potassium fertilizer, rape needs relatively little, and the boundary between proper amount and excessive amount is very small. Excessive amount often produces poison. Borax (sodium salt of boron) is the most commonly used boron fertilizer in rape production in China at present. It is low in price and convenient to use. It contains 11% boron and has less effective components than boric acid, but the effect is the same. In addition, there are boron-containing compound fertilizers, such as phosphorus boron fertilizer. Because these elements are essential elements for rape growth and development, they have significant effects on rape yield. The method of applying boron fertilizer to rape: in order to prevent rape from "flower but not fruit" and ensure high yield of rape, on the basis of applying boron fertilizer at the bottom, spraying boron fertilizer outside the root has good effect at bolting stage and when the bolting height is about 3 cm. The spraying concentration is 0.1%~0.3%, that is, 0.1~ 0.3kg borax is added with 100kg water to prepare boron-containing aqueous solution, which is evenly sprayed on rape leaves. Boron spraying should be carried out in the evening or morning of sunny days. Because the relative humidity is high at this time, the stomata open to facilitate the absorption of rape into the body. It is not suitable for spraying when it is dry and windy. Re-spraying in case of rain within 36 hours after spraying. The most critical period of boron spraying in winter rape is seedling stage and bud stage, because boron spraying in seedling stage can promote root growth and facilitate flower bud differentiation; boron spraying in bud stage can promote stem extension, not cause leaves to change from green to red due to boron deficiency, weaken photosynthesis, especially can ensure normal development of reproductive organs such as flower buds, and avoid "flower but not fruit". Therefore, spraying boron once at seedling stage and budding stage can significantly increase yield. Although foliar boron spraying had significant yield increase effect, the effect of boron spraying was lower than that of base fertilizer application because boron spraying could not meet the boron requirement of rape in time in areas or soils with severe boron deficiency. Click for more rape cultivation techniques Click for more vegetable cultivation techniques