Forrage species and off-season maize crop intercrops under no-tillage system after soybean culture in the medium Paranapanema

Abstract

The sowing of forage species under intercalary lines with off-season maize crop can contribute to reduce, in Medio Paranapanema, São Paulo state, the problems of continuous cultive of off-season maize crop and soybean, under no-tillage system, by two decades. This work is going to show the best forage specie in cultive with off season maize crop by nitrogen, the influence of the forage species in the soil and nutrient cycling, the effect of the intercrops under corn straw and weeds and the estimative of the grassland with forage in the system. Four experiments were conducted under no-tillage system fields in Campos Novos Paulista, Floríena, Plamital e Pedrinhas Paulista, and these experiments are going to conduct more than one agricultural year. The experimental units were set in a randomized block design, with four replications in subdivide plot. In the plots are going to study six forage species and off-season maize crop intercrops: 1- off season maize crop (alone), 2- off season maize crop + Brachiaria brizantha cv. Marandu, 3 - off season maize crop+ Brachiaira decumbens cv. Basilisk, 4 - off season maize crop + Brachiaira ruziziensis cv. Comum, 5 - off season maize crop + Panicum maximum cv. Tanzânia (under intercalary lines) and 6 - off season maize crop + Brachiaira brizantha cv. Marandu in total area. It was intercalaring off season maize crop and forage species lines with sowing machine with soybean spacing (around 0,45) and it was fertilized only the off season maize crop line. In the subplots are going to study four nitrogen rates ( 0, 30, 60 e 90 kg/ha), and these rates are going to supply in covering when the off season maize crop is going to have 4 until 6 leaves. It is going to study dry matter and nutrients accumulated, the weeds community and the corn and soybean grains productivity stability and mycorrhizal fungi in soil. The statistical studies will be done by variance analysis, polynomial regression and medium test with 5% significance. In addition it is going to study the economics benefits of the intercrops and the results will be shown to the scientific community, technicians and farmers. (AU)