Corn response to phosphogypsum, base saturation and lime application method

Abstract

The lime (L) and phosphogypsum (G) promote changes in the chemical attributes of the soil that can alter the development of corn. The objective was to evaluate morphological and yield components of corn after liming and G and to correlate them with yield. The treatments consisted of a 2 x 4 + 3 factorial, with two methods of application of L: surface (SL) and incorporated (IL) to obtain different levels of base saturation (BS): 44, 60, 70 and 90%. Three additional treatments were evaluated involving the use of L and G applied on the surface, being: BS 60% + 3.71 Mg ha-1 of G (60G50); BS 70% + 3.71 Mg ha-1 of G (70G50) and BS 70% + 7.42 Mg ha-1 of G (70G100). Plant height (PH), ear insertion height (EIH) and stem diameter (SD) were not influenced by the treatments. The SL increased the length of the ear (LE), number of grains per row (NGR) and mass of a thousand grains (TMG) up to BS of 72, 80 and 72%, respectively. Thus, there were no advantages of higher base saturation (BS 90%). The combination of L and G promoted improvements in ear diameter (ED), NGF, LE, TMG. The yield in IL was 445 kg ha-1 higher than SL, however when combining G and L the production increased 6 to 12% in relation to BS 44% SL. BS% levels in IL did not influence any response variable. Grain yield was positively correlated to ED, TMG, LE and PH.