Physiological responses to humic substances as plant growth promoter

Humic substances (HS) have been widely recognized as a plant growth promoter mainly by changes on root architecture and growth dynamics, which result in increased root size, branching and/or greater density of root hair with larger surface area. Stimulation of the H+-ATPase activity in cell membrane suggests that modifications brought about by HS are not only restricted to root structure, but are also extended to the major biochemical pathways since the driving force for most nutrient uptake is the electrochemical gradient across the plasma membrane. Changes on root exudation profile, as well as primary and secondary metabolism were also observed, though strongly dependent on environment conditions, type of…

• CN
  Conselho Nacional de Desenvolvimento Científico e Tecnológico
• FC
  Fundação Carlos Chagas Filho de Amparo à Pesquisa do Estado do Rio de Janeiro