Breeding cut flower cultivars of Leptospermum using interspecific hybridisation

Abstract

Leptospermum scoparium Forst. has an ideal form for a cut flower, but its use is limited by a short vase life. Flowers on cut stems typically wilt within 4-6 days of harvest. A breeding programme was initiated to develop cultivars with improved characteristics for commercial cut flower production, focusing on increasing postharvest life. A survey was conducted of 38 cultivars of L. scoparium as well as 16 other species of Leptospermum, 3 of the closely related genus Kunzea, and 1 intergeneric hybrid between L. scoparium and K. sinclairii. The vase lives of the L. scoparium cultivars studied varied from 1 to 6 days, with a modal value of 4 days. L. scoparium ‘Crimson Glory’ has been successfully hybridised to L. rotundifolium ‘Jervis Bay’. The F1 progeny of this cross lasted from 4 to 9 days in a vase with a modal value of 6.5 days. Other heritable characters included differences in leaf and flower dimensions and the accumulation of the blue anthocyanidin moiety delphinidin in the petals. © 1995 Taylor & Francis Group, LLC.