随着科学技术的飞速发展,市场上叶面肥品种种类也越来越多,大多数含有作物所必需的营养元素,可防止作物因缺素而引起的各种生理性病害。有些叶面肥含有腐殖酸、生长调节剂、生理活性物质,对改善产品品质和提高产量有一定效果。但多数叶面肥并不含杀菌剂、杀虫剂,对由真菌、细菌、病毒引起的侵染性病害,没有直接的防治作用。然而有些叶面肥厂家和经销 With the rapid development of science and technology, there are more and more varieties of foliar fertilizer on the market, and most of them contain nutrients necessary for crops to prevent various physiological diseases caused by lack of nutrients. Some foliar fertilizer containing humic acid, growth regulators, physiologically active substances, to improve product quality and increase production have some effect. However, most foliar fertilizers do not contain bactericides and insecticides, and have no direct preventive and control effects on infectious diseases caused by fungi, bacteria and viruses. However, some foliage producers and distributors