IN VITRO PROPAGATION OF BLACKBERRY AND RASPBERRY AFTER COLD STORAGE OF ENCAPSULATED SHOOT TIPS

Abstract

The paper deals with in vitro propagation of shoots of blackberry and raspberry developed from encapsulated shoot tips stored at 5°C for up to 3 months. Shoot tips of blackberry ‘Cacanska Bestrna’ and raspberry ‘Meeker’ were initially encapsulated in calcium alginate beads and stored at 5°C in darkness. A maximum of 18.8 and 6.3% of encapsulated shoot tips of blackberry and raspberry, respectively, survived one month in cold storage and formed shoots, while only few shoots of the raspberry ‘Meeker’ developed after 2 months. Multiplication index of blackberry shoots decreased gradually from the 1st to the 5th subculture, after which it increased again, without reaching the value of the 1st subculture. In comparison with the control, no marked differences in the rate of rooting and acclimatization were observed, although raspberry shoots performed worse than blackberry ones. In both cultivars, shoots from stored encapsulated explants maintained their normal morphology. These results suggest that the storage of encapsulated shoot tips neither reduces the subsequent shoot multiplication rate and rooting potential, nor influences morphology and viability of cultures.