Single superphosphate fertilizer distribution among seeder-fertilizer rows

The objective was to verify the uniformity of single superphosphate distribution among seeder-fertilizer rows and its consequences on crops. The experiment was installed in the municipality of Tibagi—PR, involving the following crop rotation in the same area: black oat ( Avena strigosa ) in 2012, corn ( Zea mays ) in the 2012–13 season, wheat ( Triticum aestivum ) in 2013, soybeans (Glycine max) in the 2013–14 season, black oat in 2014 and corn closing the cycle in the 2014–15 season. The experimental design was used in randomized blocks, considering the number of rows of the seeder-fertilizer (ranging from 11 for corn to 27 for wheat) as treatments; with three replicates. During the experimental period, 250 kg ha −1 of single superphosphate were distributed per crop at sowing, with a mean deviation of up to 14% and variation in the fertilizer mass among the seeder-fertilizer rows in up to 52%. The variables evaluated were initial population and income components. It was concluded that it is not possible to correlate the variation of fertilizer distribution among rows of the seeder-fertilizer with the variables that presented significant differences in the crops through three agricultural seasons. This fact may be related to the alternation of the highest and lowest doses of simple superphosphate. Due to the succession of seeder-fertilizers used over the years to crops seeding, there was a compensation for the random variation of fertilizer among rows and crop spacings along the crop seasons.