A Method for Determining Aluminum Response of Barley in Nutrient Solution in Comparison to Response in Al‐Toxic Soil1

Abstract
A method was developed to screen barley populations for Al response in nutrient cultures. Thirty varieties and selections were grown in tanks of nutrient solutions containing either O or 4 ppm Al at initial pH 4.8. Aluminum tolerance ratings obtained by this method were in good agreement with those obtained previously in pots of acid, Al‐toxic soils in the greenhouse and in field plots. In general, Al injury was characterized by an increase in the number of roots and a decrease in root length and root weight per plant. Highly significant (1% level) correlation coefficients were found between root length and weight (r=0.93); root weight and number of roots (r=−0.76); and root length and number of roots (r=−0.83). The correlation coefficient between root weight in solution and in soil (r=0.75) was also significant at the 1% level. The method presented is satisfactory for screening barley varieties for Al tolerance.