Bioscience Journal (Aug 2018)

Boron alters cation exchange properties of corn roots but does not decrease aluminum toxicity

  • Julierme Zimmer Barbosa,
  • Antonio Carlos Vargas Motta,
  • Rangel Consalter,
  • Volnei Pauletti

DOI
https://doi.org/10.14393/BJ-v34n1a2018-36637
Journal volume & issue
Vol. 34, no. 4

Abstract

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Most studies that have registered amelioration of Al toxicity due to root cation exchange capacity (CEC) decrease with B application were conducted using eudicotyledonous species (high root CEC). However, the effect of B/Al interaction on the root CEC values in species with low root CEC such as corn (Zea mays L.) has been understudied. Thus, this study aimed to: (1) verify if B decreases root CEC and if it benefits the growth and nutrient uptake in corn plants under Al toxicity; and (2) verify which method of root CEC analysis better differentiates the effects of B and Al. Corn seedlings were grown in complete nutrient solution with the following treatments: 0, 50, and 200 mM of B versus 0 and 300 mM of Al. Root attributes showed correlations with nutrient depletion from the nutrient solution, but nutrient depletion generally varied with transpiration in two depletion tests. The addition of B or Al in nutrient solution decreased root CEC; however, B failed to decrease Al toxicity in corn plants. The four methods used to determine CEC of corn roots had contrasting results, particularly with respect to the effect of B in the presence of Al.

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