Rapid and simple method for Al-toxicity analysis in emerging barley roots during germination

The results demonstrate the benefits of using filter-paper-based system for cultivation the germinating barley seeds for Al toxicity or Al tolerance analyses. Due to the high affinity of filter paper to Al monomeric forms, milimolar Al concentrations were required to cause similar Al toxicity symptoms of roots as micromolar Al concentrations in hydroponics: 1 mM Al had no effects on the emerging barley roots, 2 mM Al was moderately toxic but roots showed good recovery, 4 mM Al was highly toxic and 8 mM Al even lethal. Screening of eight barley cultivars revealed different rank of their tolerance to Al. The root growth inhibition positively correlated with the Al concentration in root tips.