Field performance of highbush blueberries (Vaccinium × corymbosum L.) cv. 'Herbert' propagated by cuttings and tissue culture

'Herbert' highbush blueberry (Vaccinium × corymbosum L.) plants propagated by softwood cuttings (HT) and obtained by micropropagation (TC) of axillary (AX) and adventitious (AD) shoots of 1-year-old in vitro cultures or 11-year-old cultures (SH) were compared. Propagation methods exerted significant influence on nursery and field performance of blueberries. Cutting-derived HT plants grew more slowly, produced significantly less and shorter shoots and were more variable than micropropagated plants. However, the majority of HT plants developed flowers 1 year earlier, flowered more abundantly, bore significantly larger berries than TC plants. There was no clear difference between AX and AD plants. SH-derived plants had smaller berries with the fewest seeds compared to AX and AD-obtained plants. This reveals that culture age had more significant influence than shoot source for the variation observed among micropropagation systems. The present study underlines the necessity of frequent establishment of in vitro cultures of highbush blueberry and carry them out by limited number of passages.