Foliar fertilization is a common practice to supply crops with mineral nutrients, especially under conditions of limited soil nutrient availability. As compared to soil application, foliar feeding offers a range of potential advantages: Supplying nutrients directly to the foliage bypasses the soil. Therefore, foliar feeding may act much faster than soil application. Furthermore, leaf application may prevent nutrient losses by leaching or immobilization in the soil. Thus, foliar feeding offers the possibility to correct or prevent nutrient deficiencies in a fast and environmental friendly way. However, there are also some potential disadvantages and risks associated with foliar feeding. Underdosing of nutrients may compromise the correction of nutrient deficiencies, while overdosing may result in leaf scorch and subsequently in yield reduction. The rate of foliar absorption is furthermore affected by a range of other factors such as the prevailing environmental conditions, the type of fertilizer salt and, of course, by the type of crop. Optimization of foliar feeding thus requires some knowledge of the principles of foliar nutrient absorption and the controlling parameters. Although there has been considerable progress in the understanding of theseprocesses and many pervious concepts and theories had to be abandoned or at least modified, some of the old views are still sticking in the minds of researchers and users. In his outstanding keynote lecture given at the New Ag International conference in New Delhi, Prof Dr Thomas Eichert from Germany, the world leading scientist on Foliar nutrition, addressed some of the most important misconceptions ("myths") related to the foliar application of mineral nutrients. After Eichert's paper three other experts gave papers on foliar fertilizers.
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