Guanfacine and Clonidine Reduce Defoliation and Phytotoxicity Associated with Abscission Agents

  title={Guanfacine and Clonidine Reduce Defoliation and Phytotoxicity Associated with Abscission Agents},
  author={Jacqueline K. Burns and Luis Pozo and Rongcai Yuan and Brandon Hockema},
  journal={Journal of the American Society for Horticultural Science},
Guanfacine and clonidine were combined with ethephon or metsulfuron-methyl in the spray tank and applied as foliar sprays to Citrus sinensis L. Osb. 'Valencia', Citrus madurensis Loureiro (calamondin), and Prunus persica 'Elberta' to determine their effects on leaf loss, fruit detachment force (FDF), immature fruit loss, and twig dieback. In 'Valencia' orange, 'Elberta' peach and calamondin, guanfacine and clonidine effectively reduced ethephon-induced defoliation in all three tree species… 

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