ACCUMULATION OF NITRATE AND CHLORIDE BY BURLEY TOBACCO

Abstract

Experiments were conducted to study the NO3− and Cl− interactions during uptake by burley tobacco (Nicotiana tabacum L., cult Ky 14) and the effects of their interactions on plant composition over long growth periods. Results indicated that NO3− or Cl− inhibited the absorption of the other anion by burley tobacco plants but did not influence the composition of cations. Positive linear relationships were found between NO3− and Cl− levels in solution, and the NO3− and Cl− contents in the plants in the laboratory and greenhouse studies. The inhibition of NO3− by Cl− during accumulation was also evident for tobacco plants grown under field conditions for longer periods. The interaction between NO3− and Cl− appears to be competitive during accumulation by burley tobacco. Competition between NO3− and Cl− during accumulation is proposed to be localized in the leaf cell rather than at the root–media interface.