Factors influencing phosphorus placement and effects on yield and yield parameters: A meta-analysis

As phosphorus (P) is a finite, non-renewable resource, it should be used as efficiently as possible. Different placement methods (broadcast, band, deep band, and others) can optimize the P supply for plants. Therefore, this meta-analysis evaluated 39 studies involving four major crops wheat (Triticum aestivum L.), maize (Zea mays L.), soybean (Glycine max L.), and oilseed rape (Brassica napus L.) concerning the effectiveness of different P placement methods on yield, yield parameters, and P uptake. Most authors indicated yield advantages in wheat and maize when P fertilization was applied in bands. This was confirmed by the meta-analysis indicating that especially P application in the deep band leads to yield advantages in wheat and maize. Phosphorus placement's influence on yield, yield components, and P uptake was affected by external factors, such as the site, the year of cultivation, and the crop variety. In the case of oilseed rape (Brassica napus L.), band application advantages were also demonstrated. Broadcast P was the best overall application for soybean. Further research is needed to better understand the interactions between pH, soil P content, P placement, and yield effects.