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

Braz J Biol. 2023 Dec 18:83:e277798. doi: 10.1590/1519-6984.277798. eCollection 2023.

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.

MeSH terms

  • Atrazine*
  • Crotalaria*
  • Herbicides* / toxicity
  • Zea mays

Substances

  • Herbicides
  • Atrazine
  • tembotrione
  • metolachlor
  • acetochlor