INTRODUÇÃOO Brasil é um dos países que tem maior área agrícola cultivada em sistema plantio direto (SPD), com 31,8 milhões de hectares, que correspondem a mais da metade da área agrícola do País (Febrapdp 2012). A acidez do solo é um dos fatores mais limitantes à produtividade das culturas, no mundo (Fageria 2001), sendo a calagem utilizada para a sua correção. , com incrementos de 9,3 %, para o milho, e 11,4 % e 11,3 %, respectivamente com e sem calcário, para a soja.
PALAVRAS-CHAVE:Zea mays L.; Glycine max (L.) Merrill; acidez do solo.Gypsum and lime increase soybean and maize yield and decrease drought stress During the maize and soybean cultivation process, water deficit occurs frequently and can reduce grain yield. Gypsum can be used to mitigate yield losses. This study aimed to evaluate the influence of gypsum application, with and without lime, on soil chemical properties and maize and soybean yield, in a no-till system. The experimental design was completely randomized, with six gypsum doses (0 t ha -1 , 0.5 t ha -1 , 1 t ha -1 , 2 t ha -1 , 4 t haand 8 t ha -1 ), lime application and four replications, for maize. For soybean, a 6 x 2 factorial scheme, with six gypsum doses (0 t ha -1 , 0.5 t ha -1 , 1 t ha -1 , 2 t ha -1 , 4 t ha -1 and 8 t ha -1 ), with and without lime application, and four replications was used. Soil chemical attributes and maize and soybean grain yield were evaluated. Gypsum increases the Ca 2+ levels, redistributes Mg 2+ to the 10-20 cm and 20-40 cm depth layers and decreases the Al 3+ contents in the 20-40 cm layer. Liming increases pH in the 0-10 cm depth layer and pH is not affected by the gypsum application. Gypsum increases maize and soybean grain yield, with response up to the 2 t ha -1 dose, with increments of 9.3 %, for maize, and 11.4 % and 11.3 %, respectively with and without lime, for soybean. KEY-WORDS: Zea mays L.; Glycine max (L.) Merrill; soil acidity.
