highly significantp < 0.001
Our Pearson correlation analysis revealed a highly significant positive correlation for root length, perimeter and volume of the SR, R 2 = 0.95 ( p < 0.001), R 2 = 0.97 ( p < 0.001) and R 2 = 0.87 ( p < 0.001), respectively (Fig. 6 a–c).