Foliar fertilizers are effective, and scientific selection is key
After the pegging stage of autumn peanuts, drought weather and large day-night temperature differences affect pod development, causing pods to be not plump. If foliar topdressing is carried out multiple times after the pegging stage of autumn peanuts to supplement nutrients through the leaves and raise the nutritional level of the autumn peanut plants, the ability of the autumn peanut plants to resist drought and adapt to large day-night temperature differences can be enhanced, making the pods...
"In addition to bulk fertilizers, I buy some foliar fertilizers every year. Especially under low-temperature conditions, using foliar fertilizers to promote early maturity has a very obvious effect." On March 22, Li Xiangchen, a farmer from Xinmin Tun, Limin Village, Bin County, Heilongjiang Province, who was buying fertilizer for spring plowing, told reporters. Foliar fertilizer is fertilizer applied to the leaf surface of crops during crop growth. It can generally be divided into macroelement foliar fertilizer, microelement foliar fertilizer, humic acid foliar fertilizer and amino acid foliar fertilizer. In recent years, foliar fertilizer has gained increasing favor.
Li Xiangchen is a local large-scale grower and has planted more than 150 mu of rice. He also pays special attention to the use effects of various inputs. He told reporters that this year he plans to use more foliar fertilizer to replace part of bulk fertilizers, because the price of bulk fertilizers in Heilongjiang has risen by nearly 50%, and by comparison foliar fertilizer appears even more inexpensive and good-quality. He did the math: 1 small packet of 15 ml foliar fertilizer diluted with water can spray 2 mu of land, and the selling price is only 1.2 yuan. Spraying 150 mu once costs less than 100 yuan, which is much cheaper than bulk fertilizer, which this year sells for 180 yuan per 50 kg packet.
Fast effectiveness is also a major advantage of foliar fertilizer. "Especially for drought-affected rice, after spraying foliar fertilizer, the wilted leaves visibly perk up." Li Xiangchen said. According to tests, spraying a 1%-2% concentration urea aqueous solution on the leaves allows 1/3 to be absorbed after 24 hours; spraying a 2% concentration superphosphate extract can be transported to all parts of the plant after 5 minutes. This is also particularly useful at the seedling stage of plants. Generally, the root system is not well developed and has weak absorption capacity, making yellow seedlings and weak seedlings prone to occur, and the effect of foliar fertilization is relatively obvious.
Greatly improving fertilizer utilization is generally regarded as the more important significance of foliar fertilizer. At present, the average fertilizer utilization rate in China is less than 30%, and a large amount of fertilizer has not been effectively used. Moreover, excessive fertilizer enters the soil and causes soil compaction, and enters water bodies and pollutes the environment. Foliar fertilizer, however, is sprayed directly on the leaf surface, so the utilization rate is greatly improved.
Foliar fertilizer has obvious effects, so why has it not been promoted on a larger scale? Wei Xuetao, owner of Fengshou Agricultural Materials Store in Acheng District, Harbin, told reporters: "Although foliar fertilizer takes effect quickly, it lasts for a short time, and it must be sprayed about once every 7 days. It is troublesome to use, so many farmers are unwilling to buy it." However, experts from the Plant Protection Station of the Heilongjiang Provincial Agricultural Commission explained that foliar fertilizer can be sprayed together with pesticides, which greatly reduces the labor intensity of using foliar fertilizer.
The current chaos in the foliar fertilizer market is also the biggest bottleneck restricting its development. Liu Dongsheng, the relevant person in charge of Guangxi Beihai Penshibao Company, the earliest domestic enterprise to make foliar fertilizer, told reporters that because producing foliar fertilizer is relatively simple and the state has no strict standards for foliar fertilizer, many manufacturers emerge on the market every year, holding temporary registration certificates or having not passed national approval at all, making some money for two or three years and then leaving, which greatly disrupts market order. In Wei Xuetao's agricultural materials store are displayed dozens of brands of foliar fertilizer. Li Hongwu, Heilongjiang manager of Penshibao Company, pointed to these products and said: "Farmers cannot distinguish these brands. They buy them with a try-and-see attitude. If they do not work, they will think that foliar fertilizer products of this type are all useless. This is extremely unfavorable to the development of the foliar fertilizer industry."
That foliar fertilizer is inexpensive and efficient has become the consensus of more and more people, but at the same time relevant personnel from the Ministry of Agriculture also pointed out that because foliar fertilizer is sprayed on the leaf surface during crop growth, it can only play a temporary role in supplementing nutrients. For macroelement fertilizers such as nitrogen, phosphorus and potassium, crops have large requirements, and pure foliar fertilizer is not enough; soil fertilization is also needed.