PRIMOCANE MORPHOLOGY AND LEAF SURFACE CHARACTERISTICS OF GREENHOUSE-GROWN RED RASPBERRY CULTIVARS

Abaxial and adaxial surfaces of the distal leaflet of the third leaf f rom the apex, and primocane morphology of the following internode, of six greenhouse-grown red raspberry (Rubus idaeus L.) cultivars ('Algon quin', 'Chilliwack' 'Comox', 'Haida', 'Meeker', and 'Tulameen') were e xamined. Scanning electron micrographs revealed tangled, woolly pubesc ence, irregularly shaped cells, and stomates on abaxial leaf surfaces. 'Algonquin' exhibited the densest pubescence, and 'Haida' the sparses t. Smooth-walled, uniserate trichomes were present on adaxial surfaces . 'Chilliwack' displayed greatest trichome abundance. Trichomes were l ess commonly seen on the adaxial leaf surface of 'Algonquin', 'Haida', and 'Meeker'. Relative abundance of spines on 3-month-old primocanes was dense for 'Tulameen', moderate-dense for 'Meeker' and 'Comox', mod erate for 'Chilliwack', sparse-moderate for 'Algonquin', and sparse fo r 'Haida', Spine length was greatest for 'Tulameen', and was greater i n 'Meeker' than in 'Haida'.