Effects of volatile organic compounds (VOCs) emitted by Suillus bovinus (Sb) on the growth of Pinus massoniana. Seedlings grown in the absence of S. bovinus VOCs acted as controls (NM). a Number of branches, b root length, and c fresh weight of P. massoniana. n = 10. Data shown are mean values ± the standard error. * P < 0.05, ** P < 0.01. P. massoniana seedlings grown in the d absence and e presence of S. bovinus VOCs for 28 days. Scale bars: 2 cm.