Q: Under what circumstances should the crop be sprayed with fertilizer? Cao Yiping (Professor, China Agricultural University): Foliar fertilization is an auxiliary way of crop fertilization. Although crops rely primarily on roots to absorb the nutrients they need from the soil, stems and leaves can also absorb nutrients. Spraying fertilizing solutions on the foliage is also called root fertilization, but it cannot replace root fertilization. Under normal circumstances, on the basis of soil fertilization, the use of foliar fertilization to help the crop supplement some of the micro-nutrients or growth regulators, etc., which is necessary to increase crop yield and improve quality. In addition, under certain special circumstances, such as the fertility or the results of field crops in the reproductive growth stage in the late growth period, the carbohydrates required for development are used in large quantities in fruits and other parts, resulting in decreased root activity and decreased nutrient absorption. It needs to be supplemented by foliar fertilization; in the case of drought in the topsoil and no irrigation conditions, the effective nutrient transport in the rhizosphere soil is poor; or in the plots of stagnant water, crop roots cannot absorb nutrients normally due to lack of oxygen. Under special circumstances, it is necessary to give full play to the role of leaf nutrition and fertilization. Q: What are the advantages and disadvantages of foliar fertilization? Cao Yiping: The main feature is that leaf nutrition provides faster nutrients than roots, but the amount of fertilizer is limited and the effect is short-lived. The efficiency of leaf nutrition is related to the structure of the leaves. The permeability of the leaves of different types of crops to mineral nutrients varies greatly. In particular, the horny thick leaves have low permeability. Leaves of crops such as olives, citrus and coffee. Liquid fertilizer droplets do not easily infiltrate the leaves, and liquid fertilizer droplets fall off the surface of the leaves and cause loss. The advantages of foliar fertilization are: the direct supply of nutrients is fast, avoiding the fixation and degradation of nutrients in the soil, and the nutrient utilization efficiency is higher than that of soil fertilization. The disadvantage of foliar fertilization is that the fertilizer effect is transiently limited. It is an auxiliary fertilization method. Q: What skills do you need to master when fertilizing leaves? Cao Yiping: 1. The first type of fertilizer is mainly used to supply micronutrients, but the combination of a large number of trace elements is conducive to the absorption and utilization of nutrients. The specific determination of which fertilizer species depends on the actual needs of the crop, depends on the type of restrictive nutrients in the soil; selecting a good formula fertilizer can improve the targeted application of foliar fertilizer. Do not choose the kind of "full nutrition" Shiquan rehydration, the price is expensive and untargeted, but the effect is not good. 2. The concentration of leaf fertilizer should be mastered. If the concentration is too high, the leaves will be damaged, and the fertilizer effect will be reduced. Low concentration does not work. 3. Spraying time and weather conditions should be selected. 4. Spraying frequency is usually sprayed 2 or more times. Dog Jerky,Chicken Jerky For Dogs,Duck Jerky For Dogs,Jerky Treats For Dogs Jiangxi Welton Pet Products Co., Ltd. , https://www.weltonpetcare.com