Abstract
Fundamental aspects of foliage production of kudzu-vine are evaluated in this paper, including time of current year's stem emergence from buds at the nodes of overwintering stems, the number of current year's stems produced per node of overwintering stem (NCPN), the difference in the contribution of left, middle and right buds to the emergence of current year's stem and percentage mortality of current year's stem. Current year's stem emergence commenced in early April and terminated in early June, although about 80% of the total number of current year's stems emerged by the end of April. NCPN decreased gradually from 0.61 in May to 0.15 in October in the overwintering stems with one vascular bundle ring (one-ring overwintering stems). In two-ring overwintering stems, NCPN did not show a distinctly seasonal change, ranging from 0.11 to 0.18. NCPN for overwintering stems with more than three vascular bundle rings was even lower. Nodes of overwintering stems were classified into seven types on the basis of which of the three buds produced a current year's stem. The left and right buds made a greater contribution than the middle one to the production of current year's stems. In one-ring overwintering stems, percentage mortality of current year's stems started increasing from July and reached the highest value (22.2%) in the final examination. Percentage mortality was generally lower in two-ring overwintering stems than in one-ring stems. No dead current year's stems were observed in the overwintering stems with more than three vascular bundle rings. From these results and the fact that the nodes of one-ring overwintering stems were 76% of the total number of nodes examined, it is concluded that the emergence of current year's stems occurs mainly on buds of one-ring overwintering stems and that the left and right buds play a more important role than the middle one in the current year's stem-emergence.
