Fig. 4

Relationship between the severity of B toxicity-induced leaf necrosis and leaf B concentration for a set of current Australian barley varieties. Symptoms were assessed visually three times during the growth of plants to full maturity and an average score determined (0 = no necrosis; 6 = severe necrosis). The penultimate leaves from five tillers were sampled at mid-grain fill for each measurement of leaf B concentration. HvBot1 allele type for each variety is indicated (closed circles = Clipper; open circles = Sahara (single-copy); open squares = Sahara (multi-copy); open upward triangles = Alexis; open downwards triangles = Morex). The dashed line indicates a weak positive, linear correlation between the two parameters (R² = 0.235)