Blackberry propagation by non-leafy floricane cuttings

Abstract

One- or two-node hardwood cuttings were taken from 9-year-old 'Triple Crown' and 'Siskiyou' blackberry (Rubus) plants on 5 Nov. 2009, 3 Dec. 2009, and 21 Jan. 2010. The response of cuttings with and without partially excised axillary buds to an application of cytokinin was compared with control cuttings with intact axillary buds and no cytokinin. Differences in root development were evident in the two cultivars tested. The cuttings of 'Siskiyou' and 'Triple Crown' callused on cut ends, but many of the adventitious roots developed from the base of the axillary buds. Shoots emerged from the bud in %90% of 'Siskiyou' cuttings stuck in November, December, and January. Rooting occurred in more than 90% of cuttings stuck in November and December but declined in cuttings stuck in January. In 'Siskiyou', bud excision had no effect on shoot and root emergence, but cytokinin treatment suppressed rooting in cuttings collected in November and January. Shoot emergence and rooting were poorer in 'Triple Crown' cuttings than in 'Siskiyou'. In 'Triple Crown' cuttings, partial excision of buds reduced shoot emergence only in January but had no effect on rooting at three sticking dates. Cytokinin treatment improved shoot emergence in November and December but reduced rooting in January. The enclosed system is a viable method for propagating 'Siskiyou' blackberry by non-leafy floricane cuttings.