Consórcio de plantas de cobertura em segunda safra para sistema plantio direto no ecôtono Amazônia-Cerrado

Abstract

Integrated agricultural production systems aim to improve crop cultivation, as is the case with the no-till system (SPD), which seeks to directly sow seeds on crop residues without using primary and secondary soil preparations. The protection provided by crop residues helps prevent erosion and nutrient loss due to leaching and solar exposure. To bring about improvements, the idea of intercropping various plants has been considered, taking advantage of the positive aspects of each plant. In this way, each crop contributes a better quantity of macronutrients to the soil, effectively recycling nutrients for future crops. Therefore, the objective of this study was to evaluate the use of intercropping with forage plants in the second crop for no-till farming in the northern region of Mato Grosso, Brazil. The experiment was conducted at Santana Farm in the municipality of Sorriso, MT, Brazil, using a completely randomized design with six replications. The treatments included corn cultivation in monoculture (control); corn intercropped with Ruzigrass; corn intercropped with Ruzigrass and Crotalaria spectabilis; grain sorghum with Estilosante cv. Bela; BRS Ponta Negra sorghum; Ruzigrass with Crotalaria spectabilis; and a six-way polyculture (Ruzigrass with Crotalaria spectabilis, forage turnip, buckwheat, pigeon pea, and niger). Laboratory analyses were conducted at the Brazilian Agricultural Research Corporation (Embrapa) Agrossilvipastoril in Sinop, MT, Brazil, between March 2021 and March 2022. The treatments involving grass (corn + grass, corn + grass and Crotalaria, grass + Crotalaria, six-way polyculture) showed higher crop residue production and macronutrient contribution compared to the other treatments. Single-crop corn yielded better results in grain productivity compared to the other corn treatments, with average stem diameter, plant height, and ear height of 16.54, 1.73, and 72.49, respectively. The presence of grass in intercropping with corn can potentially harm cereal productivity. The presence of crop residues positively contributed to soil protection and the supply of N, P, and K.