Effect of root pruning radius and time on root biomass and horizontal distribution in Helianthus tuberosus

Studying the effects of the root pruning radius and time on root biomass and horizontal distribution in Helianthus tuberosus clarified the influence mechanism of cutting the roots regarding tuber yield from the change in root biomass and horizontal distribution under different cutting root treatments. The results showed that the biomasses of the main root, root, primary root, rhizome, and fibrous root were significantly higher than that of the root that was not cut (P<0.05), and the biomasses of the main root, root, primary root, rhizome, and fibrous root showed a decreasing trend with an increase in the root cutting radius. The root, main root, primary root, rhizome, and fibrous root biomass showed first an increase and then a decrease that was aligned with the cutting root time delay. The root, main root, primary root, rhizome, and fibrous root biomasses decreased gradually with an increase in the distance from the main root center under the root cutting treatments. The effect of root pruning time and radius on the root, main root, primary root, rhizome, and fibrous root biomasses decreased as the distance from the main root center.