The effect of planting depth, disbudding, and root pruning on root weight and aconite alkaloid content of the tuberous root of aconite

The tuberous root of aconite, Aconiti tuber, contains tonic but poisonous aconite alkaloids, such as aconitine, hipaconitine and mesaconitine. The standardization of the cultivation protocols must be established, since the quality of the crude drug, especially the content of aconite alkaloids, is influenced by cultivation conditions. Here, we report the effects of planting depth, disbudding and root pruning on the content of the aconite alkaloids as well as on the weight of the root tuber of aconite. The daughter root tubers of shallow-planted plants showed a significantly higher content of aconitine, hipaconitine and sum of aconite alkaloids per unit weight than those of deeply planted root tubers (control group), while the average weight per root tuber was lower than that of the control group. The total weight of the daughter root tubers per plant of the disbudding group was significantly higher than that of other groups, including the root-pruning group whose average weight per tuber was the highest. In conclusion, disbudding is effective in achieving both higher content of aconite alkaloids and heavier total weight of the root tuber.