Our research project is part of a long-term experiment, installed in 2002/2003, at the College of Agricultural Sciences, UNESP, Botucatu (SP-Brazil). Since its deployment, 15N persistence and distribution within soil-maize/forage-soybean system and the activity and microbial communities in relation to soil N cycle have never been evaluated. Thus, following the experiment, which should probably be the only one in the State of São Paulo with more than 17 years of evaluation, our aim is to evaluate the effect of surface application of lime and/or gypsum in long-term on the chemical, physical and biological soil attributes, root growth, plant nutrition and yield of maize intercropped with Urochloa ruziziensis and soybean in succession, as well as N- (15NH4)2SO4 efficiency in the soil-plant system. Fieldwork from this proposal has been conducted since October 2016, when limes and/or gypsum doses were last applied. The soybean sowings occurred in the first half of October of each year and the maize intercropped with Urochloa ruziziensis always sown in March of each year. This crop sequence will be carried out during the 2016/2017, 2017/2018, 2018/2019, 2019/2020. The experimental design will be in randomized blocks with 4 replicates. The treatments are 1: without application of lime and gypsum (Control); 2: Lime application (13,040 kg ha-1); 3: Gypsum application (10,000 kg ha-1); 4: Lime and Gypsum application. Following evaluations will be carried out: mineral nutrition, grain yield of crops, root growth of the crops, 15N recovery in the soil-plant system, chemical, physical and biological attributes of the soil and fractionation of organic matter.
|Datum van beschikbaarheid||23 apr 2021|