Abstract
ABSTRACT: Corn and forage intercropping system has been commonly used for pasture establishment or renewal. In addition, the use of reduced doses of herbicides selective to corn has facilitated coexistence by reducing competitiveness against forage species. This study aimed to evaluate the effects of mesotrione underdoses in a corn and Urochloa brizantha intercropping on weed population dynamics, corn yield, and forage performance and nutritional quality. For this purpose, five mesotrione doses were tested (0.0, 9.6, 19.2, 38.4, and 57.6 g ha-1) in corn and forage intercropping and monocultures. Individual density and weed dry matter were influenced by mesotrione doses, intercropping, and precipitation distribution over the evaluated period in the intercropping and pasture. In intercropping, Alternanthera tenella and Commelina benghalensis were the most important species because they could not be controlled by the herbicide. After intercropping, A. tenella and C. benghalensis presented higher relative importance (RI) in the formed pasture during the rainy season, while Conyza bonariensis and A. tenella presented the highest RI during the dry season. Corn grain yield was not affected by the presence of grass, but forage yield was affected by the competition with corn. Mesotrione doses did not affect the yield and nutritional quality of the forage. The effects on mineral matter, crude protein, and acid detergent fiber in the forage were due to the coexistence with corn when compared to the control grown in monoculture.
Highlights
Areas cultivated in the integrated crop-livestock system (ICL) have increased in Brazil especially in the Cerrado region in the form of intercropping, rotation or succession of crops between forage species and food crops, mainly soybean and corn
Considering the evaluations performed at 43 and 109 days after application (DAA) of mesotrione (Table 1), the occurrence of 20 weed species was observed in the intercropping distributed into nine botanical families
Considering the entire weed evaluation period (43, 109, 178, and 344 DAA), ALTTE response to mesotrione underdoses is supported by the results obtained by Timossi (2009), who did not observe control of this species when tested mesotrione associated with atrazine
Summary
Areas cultivated in the integrated crop-livestock system (ICL) have increased in Brazil especially in the Cerrado region in the form of intercropping, rotation or succession of crops between forage species and food crops, mainly soybean and corn. Considering the evaluations performed at 43 and 109 DAA of mesotrione (Table 1), the occurrence of 20 weed species was observed in the intercropping distributed into nine botanical families.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
