Abstract The supply of sulfur (S) fertilizers, such as phosphogypsum, to new agricultural frontiers has been hindered by the high cost of freight. However, this problem could be resolved by utilizing deposits of rock in the affected regions. Accordingly, a greenhouse study was designed to evaluate the effect of S source and rate on soybean yield. Five S rates (0, 50, 100, and 200 mg kg−1) and five S sources (S-phosphogypsum, S-Niquelândia rock, S-Araripina rock, S-Grajaú rock, and S-Sulfurgran [90% S0 + 10% bentonite]) were applied to soybean grown in two soil types (Typic Ultisol and Typic Oxisol), which differ in clay content. Regardless of soil type, the application of P-phosphogypsum resulted in a higher grain yield. However, application of the other S sources also improved grain yield as well as total dry weight; S application, in general, improved soybean yield components (number of grains per pod, number of pods per pot, and weight of pods per pot), photosynthetic rate, chlorophyll content, and the S levels of leaves and grains as well as the available sulfate (SO42-) levels in the soil. Therefore, for soybean grown in Typic Ultisol and Typic Oxisol, different S sources effectively improve a variety of variables that ultimately improve grain yield.

中文翻译：

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硫源和硫磺用量对亚热带土壤大豆产量和产量构成的影响

摘要 高昂的运费阻碍了硫（S）肥料（如磷石膏）向农业新领域的供应。然而，这个问题可以通过利用受影响地区的岩石沉积物来解决。因此，设计了一项温室研究来评估硫源和用量对大豆产量的影响。五种 S 比率（0、50、100 和 200 mg kg−1）和五种 S 源（S-磷石膏、S-Niquelândia 岩石、S-Araripina 岩石、S-Grajaú 岩石和 S-Sulfurgran [90% S0 + 10% 膨润土]) 应用于生长在两种土壤类型（典型 Ultisol 和典型氧化土）中的大豆，这两种土壤类型的粘土含量不同。无论土壤类型如何，磷石膏的施用都会导致更高的谷物产量。然而，其他硫源的应用也提高了谷物产量和总干重；S应用，一般来说，改善大豆产量成分（每荚粒数、每盆荚数和每盆荚重）、光合速率、叶绿素含量、叶片和籽粒的 S 水平以及有效硫酸盐 (SO42-) 水平在土壤中。因此，对于在 Typic Ultisol 和 Typic Oxisol 中生长的大豆，不同的硫源有效地改善了各种变量，最终提高了谷物产量。