Figure 6

Effects of companion cropping with potato onion and potato onion root exudates on soil available sulfur content.
(A) Effects of companion cropping with potato onion on the available sulfur content of tomato rhizosphere soil. (B) Effects of inoculation with V. dahliae on the available sulfur content of tomato rhizosphere soil. (C) Effects of potato onion root exudates on soil available sulfur content. The data are presented as the means ± SD, n = 3. The small letter “a” above the column represents no significance between the two groups of mean values (p > 0.05).