Brazilian Journal of Biology (Dec 2023)

Selectivity of herbicides used in corn on Crotalaria ochroleuca G. Don

  • P. V. Silva,
  • B. F. Schedenffeldt,
  • E. S. Medeiros,
  • D. Z. Molina,
  • M. K. Pagliarini,
  • P. A. V. Salmazo,
  • M. Mauad,
  • P. A. Monquero,
  • F. C. Munaro,
  • L. Y. Shirota,
  • G. P. Silva,
  • M. S. Monteiro,
  • R. D. C. Dias,
  • R. P. N. Borges

DOI
https://doi.org/10.1590/1519-6984.277798
Journal volume & issue
Vol. 83

Abstract

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Abstract In the cropping systems that integrate the corn crop, the insertion of Crotalaria ochroleuca G. Don is predominantly intercropped. In this context, there is a need to observe herbicides that present selectivity for this sunn hemp species. The objective of this study was to evaluate the selectivity of pre and post-emergent herbicides on C. ochroleuca. Two field experiments were conducted in randomized blocks with four replications, involving the pre-emergence and post-emergence application of different herbicide treatments. For the pre-emergent ones, amicarbazone, atrazine and flumioxazin provided phytotoxicity higher than 90% and, consequently, low plant biomass. On the other hand, acetochlor and s-metolachlor did not cause phytotoxicity and did not affect the dry mass of crotalaria. In post-emergence, atrazine + mesotrione showed phytotoxicity >95%, followed by nicosulfuron and 2.4-D with phytotoxicity between 50-60%, whereas tembotrione did not cause injury to the plants. Thus, it was found that among the pre-emergent, acetochlor and s-metolachlor were selective, and for the emerging powders, only tembotrione was the most selective for all parameters analyzed.

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