Soil chemical attributes, nutrient uptake and yield of no-till crops as affected by phosphogypsum doses and parceling in southern Brazil

This study evaluated soil chemical attributes, leaf nutrient concentrations and grain yield of corn (Zea mays), barley (Hordeum vulgare), common bean (Phaseolus vulgaris) and wheat (Triticum aestivum) as affected by phosphogypsum (PG) rates and split application to a Typic Hapludox under no-till from Southern Brazil. A Randomized complete block design was used, with factorial treatment structure (5 x 2) consisting of increasing PG rates (0, 3, 6, 9 and 12 Mg ha−1) either in single or split (half dose, two consecutive years) application. PG rates have reduced concentrations of Al3+, increasing Ca2+, SO42- and pH values in soil layers up to 0.8 m. Leaf concentrations of Ca (between 28 and 42%) and S (between 6% and to 50%) increased in all crops, while leaf levels of Mg decreased on corn (−16%), bean (−22%) and wheat (−14%) by PG rates. Compared to the control, PG rates between 4.0 and 6.1 Mg ha−1 promoted increases of 11%, 10% and 10% on corn, barley and wheat yields, respectively. There was no effect of PG on common bean's yield. Phosphogypsum was effective for improving soil fertility, plant nutrition and crop yields. Applying the PG annually at one-half rate gave best overall results.