Fig. 4. Efficiency in use of the rhizobial symbiosis of six common bean recombinant inbred lines inoculated with R. tropici CIAT899 and grown under sufficient (white circle)versus deficient (gray circle) P supply. The equations inserted in the graphs describe the regression function under P-sufficiency (light gray text) and P deficiency (dark graytext), respectively. Data are means and standard deviation of four replicates calculated by difference between plants harvested at 15 and 42 DAT. *, **Significant differenceat P < 0.05 and P < 0.01, respectively.