Yield, yield components, soil fertility, and nutritional status of soybean as influenced by limestone and copper interactions

Continuous limestone application can inhibit the copper (Cu) uptake by plants. This experiment was carried out in greenhouse conditions using two soils (Typic Oxisol and Typic Entisol) with different clay and soil organic matter (SOM) levels to evaluate the effects of liming on Cu fertilization. The treatments consisted of two dolomitic limestone rates (0 and 7.5 g per pot, equivalent to 0 and 5.0 Mg ha(-1)) and five Cu rates (0, 2, 4, 8, and 16 mg kg(-1)). Regardless of the soil type, the limestone and Cu rate interaction did not affect the grain yield (GY), however, they did increase the productivity, shoot dry weight yield (SDWY), number of grains per pod, number of pods per pot, pod weight per pot, weight of 100 seeds, root volume, photosynthetic rate, and chlorophyll, and Ca, Mg, and Cu contents in the soil and leaves. It was concluded that for soybeans cultivated in Typic Entisol and Typic Oxisol, there was no association between 5.0 Mg ha(-1)of limestone and the Cu rates. However, in isolation, limestone and Cu rate caused a significant increase in the soybean productivity, physiological components, and yield characteristics.