ROLE OF BIOFERTILIZERS IN ACCUMULATION OF NICKEL IN SUNFLOWER (HELIANTHUS ANNUUS L.) AND THE EFFECT OF NICKEL ACCUMULATION ON ENDOGENOUS LEVEL OF HORMONES IN SUNFLOWER

Abstract

The objective of the study was to determine the effect of Biofertilizers i.e. Phosphate solublizing
bacteria (PSB), Effective Microorganism (EM) and Rhizobium in the uptake and accumulation of
nickel by different parts of sunflower (Helianthus annuus L.). The results revealed that all
biofertilizers has increased accumulation of nickel significantly as compare to control during both
stages. At different concentrations of nickel that were applied externally to the plants, different
fertilizers show different behavior. At lowest external concentration of nickel Rhizobium treated
plants has maximum accumulation while at highest external concentration of PSB and EM treated
plants accumulate maximum nickel. Translocation of nickel in treated plants was also increased as
compare to control plants during vegetative stage of development while insignificant during 50%
flowering stage. Accumulation of nickel was also increased as the external concentration increased.
In addition, effect of nickel accumulation on Gibberellins (GA) and Indole-acetic acid (IAA)
contents were also observed in leaves of sunflower at vegetative stage. Both GA and IAA contents
were affected by nickel accumulation.