Mass Propagation of Highbush Blueberry Using Short Cut Dormant Shoots

Abstract

In order to produce a mass propagation method of highbush blueberries (Vaccinium corymbosum L.), short cut (2 to 3 cm) one-year-old dormant shoots were used. Sprouting of axillary buds on the dormant shoots was promoted at about 20°C in a dark chamber. Sprouting of axillary buds was inhibited especially in ‘Blueray’ as compared with ‘Dixi’ under the dark condition. The axillary buds of both cultivars sprouted rapidly under lighting for 16 h per day using fluorescent lamps. Application of 300 ppm and 600 ppm 6-benzyladenine did not promote the sprouting of axillary buds of short cut dormant shoots. When new shoots on the short cut dormant shoots grew to 1 cm under the 16-h lighting condition and the dark condition, after sprouting of axillary buds on the dormant shoots was promoted under 16-h lighting, the short cut dormant shoots were inserted into propagation beds (1 : 1 mixture of peat moss and Kanumasoil). The bases of new shoots were buried so they were not exposed. About 90% of cuttings rooted. Roots were formed almost at the basal parts of the current shoots. This propagation method could obtain a 3 times greater number of rooted cuttings than the customary method.