Fig. 9. Nodule development after root infected with Rhizobium leguminosarum bv. viciae
3841 and grown for 14 days in FP media containing various concentrations of nZnO. Bacteroid
numbers per 0.1 mm2 in nodule, in most mature infected zone. Asterisks indicate
significant differences from the control (⁎⁎⁎: p b 0.001).