Chemical and biological attributes of soil and soybean yield in integrated systems in the Cerrado of Northeast Brazil

Authors: SILVA, ALCILANE ARNALD - State University Of Piaui; LACERDA, JULIAN JUNIO DE - State University Of Piaui; CARVALHO, SUZANE PEREIRA - State University Of Piaui; FERREIRA, RUBENS DE SA - State University Of Piaui; DE BRITO, RAMILOS RODRIGU - State University Of Piaui; VOGADO, RENATO FALCONER - State University Of Piaui; NETO, RAIMUNDO BEZERR - Embrapa; SAGRILO, EDVALDO - Embrapa; Cavigelli, Michel; DE SOUZA, HENRIQUE ANTUNE - Embrapa

Submitted to: Soil Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/28/2024
Publication Date: 6/20/2024
Citation: Silva, A.O., Lacerda, J. ., Carvalho, S., Ferreira, R., De Brito, R.E., Vogado, R.E., Neto, R.A., Sagrilo, E., Cavigelli, M.A., De Souza, H.S. 2024. Chemical and biological attributes of soil and soybean yield in integrated systems in the Cerrado of Northeast Brazil. Soil Research. 62. Article eSR23120. https://doi.org/10.1071/SR23120.
DOI: https://doi.org/10.1071/SR23120

Interpretive Summary: Corn intercropped with forage grasses in tropical locations can increase the yield of a succeeding soybean crop and improve soil chemical and biological properties compared to monoculture corn. Since these systems have not been evaluated in the Cerrado of Northeast Brazil, this study was conducted to fill that gap. Corn was grown in monoculture and intercropped with six different forage grasses followed by two successive soybean crops. Results showed that soybean yields were, on average, 15% greater following the corn+forage grass intercropped systems than following monoculture corn. Soil chemical and biological properties after soybean harvests were also improved following various intercropped systems compared to the corn monoculture. Results will be of interest to farmers, scientists, policy makers and all those interested in improving the productivity and sustainability of cropping systems in this region.

Technical Abstract: For the Cerrado of Northeast Brazil, little is known about the effects of forage grasses intercropped with maize (Zea mays) on soil chemical and biological attributes and on a succeeding soybean (Glycine max) crop’s yield and nutrition. This study evaluated these effects in the Cerrado of Piauí, Brazil. In the 2016/2017 cropping season, maize (M) was grown in monoculture and intercropped with the forage grasses Zuri (Megathyrsus maximus cv. Zuri), Massai (Megathyrsus maximus cv. Massai), Tanzania (Megathyrsus maximus cv. Tanzania), Tamani (Megathyrsus maximus cv. Tamani), Marandu (Urochloa brizantha cv. Marandu) and Ruziziensis (Urochloa ruzizinesis). In the 2017/2018 and 2018/2019 cropping seasons, soybean was grown on the same plots. Soil chemical attributes were evaluated in the 0-0.1, 0.1-0.2 and 0.2-0.4 m depths and biological attributes in the 0-0.1 m depth. Soybean leaf nutritional status was measured in stage R2 and soybean grain yield was estimated at the end of each cropping cycle. The data were subjected to analysis of variance and the means were grouped by the Scott-Knott test. In the 2017/2018 cropping season, highest soil potassium concentrations in the 0-0.1 m depth were observed following M+Zuri and M+Massai. Soybean grown after M+Zuri, M+Tanzania, M+Marandu and M+Ruziziensis had the highest Ca and lowest Al concentrations in the 0.2-0.4 m depth. In the 2017/2018 cropping season, soybean grown after monoculture maize, M+Tamani and M+Marandu promoted the highest soil basal respiration, whereas in the 2018/2019 cropping season, soybean following M+Zuri, M+Tanzania and M+Ruziziensis had the highest values. Intercropping maize with forage grasses of the genus Urochloa increased the soil humic substances and carbon concentrations, whereas intercropping maize with species of the genus Megathyrsus improved the soil chemical and biological attributes. Intercropping maize with forage grasses increased the cumulative average of the succeeding soybean grain yield by 15% over two seasons.