Aluminium and manganese effects on beans

Abstract

Thirty eight bean (Phaseolus vulgaris L.) cultivars were grown in nutrient solution under a factorial treatment using 4 levels of Al (0, 6, 12, 18 and 24 ppm) and 4 levels of Mn (0, 30, 60, 90 and 120 ppm) to study their behavior in presence of Al and Mn. By applying regression analysis to dry matter yield data it was possible to classify said varieties to Al effect in a. Tolerant – cultivars whose maximum yield appeared in the presence of the element at 1416 ppm: Jalo, Mulatinho Paulista, Ricobaio 1014 and Roxo 760; b. Moderately sensitive – cultivars whose minimum yield occurred in solutions having between 14 and 15 ppm of Al: Jamapa and Porrillo Sintético; c. Sensitive – cultivars whose yield showed a minimum when the nutrient solution had between 2 and 9 ppm of Al: Carioca, Costa Rica, Costa Rica 1031, Cuva 168 N, Goiano Precoce, Rico Pardo, Rio Tibagi and Tambá. Mn toxicity regression analysis allowed the following classification: a. Moderately sensitive – cultivars showing minimum yield when the nutrient solution contained from 102 to 118 ppm of Mn: Carioca, CR 911, Cuva 168W, Rico Pardo and Rio Tibagi; b. Sensitive - cultivars showing minimum yield when the nutrient solution presented from 72 to 99 ppm of Mn: Costa Rica 1031, Goiano Precoce, Jamapa, Porrilio Sintético and Rosinha. The remaining cultivars could not be classified because the estimated values of Al or Mn levels which would allow for maximum of minimum growth fell outside the experimental concentration (0 > Al > 24 and 0 > Mn > 120). For this reason it was not possible to draw safe conclusions on the data obtained.