Influence of 6-benzylaminopurine spray time after pinching on growth and flowering of Veronica dahurica Steven

Abstract

Veronica dahurica Steven (family Scrophulariaceae) is an ornamental plant from Korea. The aim of the present study was to produce multiple-branched plants by using 6-benzylaminopurine (BA) spray application at several time intervals after pinching. All 10 cm long plants were sprayed with 0, 500, 1000, and 2000 mg·L^-1 BA at 0, 7, and 14 days after pinching. Growth characteristics were examined 10 weeks after pinching and flowering time was recorded. The number of branches was highest in the group sprayed with 1000 mg·L^-1 BA at 0 d after pinching. The greatest plant height was observed in the group treated with 1000 mg·L^-1 BA 14 d after pinching and the minimum plant height was observed in the group sprayed with 500 mg·L^-1 BA at 0 d after pinching. The groups sprayed with higher BA concentrations and with longer intervals between pinching and spraying showed greater delay in the time to first flower. The flower length was decreased in the pinched and BA-treated group compared with the control. Thus, BA application and pinching could promote multiple branch induction and control flowering time in V. dahurica Steven.