Spraying Technology and Foliar Application Result in a Smooth Layer of the Spray: a Literature Review

Abstract

Using of foliar fertilizer application is an important issue in many crops plantation in different countries. Various studies have been conducted on this method, especially with fruits and horticulture. Few studies were performed on essential crops such as maize compared to the orchards. Concerning crops, most of these studies were performed using foliar spraying with phosphorus, and potassium, and a few attempts were carried out with foliar fertilizer during the season at different concentrations starting from the first stage of the plant. The foliar application may be sprayed with a suitable concentrate depending on the type of crop planted, growth stage, leaves age, and physicochemical properties of the sprayed liquid. As reported in the current literature, there are previous studies on this application with insufficient knowledge of mechanisms and factors governing the nutrient uptake by leaves that still need to be improved. The insufficient information about the effect of foliar fertilizer at different application rates is one of the reasons that the study focused on it, which was probably the leading cause of sometimes controversial effects with foliar fertilizers being reported. Most previous studies revealed that is necessary to apply foliar fertilizer on the plant leaves at a proper concentration and application rate compatible with the age of the crop applied. The results also indicated that a suitable concentration of foliar fertilizer no doubt leads to improved fertilizer effectiveness and can even increase plant growth activity, especially when spraying with modern technology. For an optimum both of the crop vegetative growth and yield response to foliar fertilization, it is possible to diagnose the optimum growth stage of the plant and leaf age for the starting of foliar fertilizer application related to metrological conditions such as the air temperature, and relative humidity at the time of spraying. It is necessary to recommend the crop growth stage before foliar application at a known application rate and concentration to a crop to achieve maximum efficiency at low cost as possible.