Uptake and translocation of imidacloprid via seed pathway and root pathway during early seedling growth of corn

Pest Manag Sci. 2020 Nov;76(11):3792-3799. doi: 10.1002/ps.5930. Epub 2020 Jun 17.

Abstract

Background: A systemic seed treatment can be taken up into shoot tissues during early corn seedling growth. However, the pathway that a systemic compound is taken up, either from seed or root uptake to shoot tissues is not fully understood. To study the single contributions of seed pathway and root pathway for the uptake and translocation of imidacloprid seed treatment, two methods were developed: A seed treatment method and a growing media/hydroponic solution delivery method. The seed treatment method employed a live and dead seed separated with plastic wrap to provide a barrier. The growing media/hydroponic solution delivery method quantified the capacity for uptake by seeds and roots.

Results: The seed pathway transported 1.9-2.5 times more imidacloprid into shoot tissues when compared to the root pathway at the same dosage rate. The higher amount of imidacloprid taken up and translocated by the seed pathway was attributed to the fact that the corn seeds were in direct contact with high provided concentrations of imidacloprid. However, the root pathway showed 7.9-9.5 times higher capacity for transporting imidacloprid into shoot tissues when compared with the seed pathway. Whenever imidacloprid was taken up by seed or root, amounts of imidacloprid were measured in both tissues of seed and root.

Conclusion: The seed pathway transported more imidacloprid than the root pathway during early seedling growth since corn seeds were contacted by higher concentrations of imidacloprid. Both seed pathway and root pathway were occurring concurrently during early seedling growth of corn. © 2020 Society of Chemical Industry.

Keywords: corn; imidacloprid; seed treatment; translocation; uptake.

MeSH terms

  • Germination
  • Neonicotinoids
  • Nitro Compounds
  • Plant Roots
  • Seedlings*
  • Seeds
  • Zea mays*

Substances

  • Neonicotinoids
  • Nitro Compounds
  • imidacloprid