CALLUS INDUCTION FROM ENDOSPERM CULTURE OF BLACKBERRY

The endosperm from self-pollinated seeds was aseptically excised about 28 days after pollination, placed for 5 min in a solution of 1% citric acid to avoid oxidation and then transferred on MS medium supplemented with 3% sucrose, 0.7% agar Bacto-Difco, different combinations of various growth regulators (IAA, NAA 2,4-D, 2iP, BA, Zea, GA₃) and with or without 400 mgl^-1 casein hydrolysate, totalling 28 media.

Callus induction was strongly influenced by genotype and by the presence of casein hydrolysate instead of glycine.
Only from ‘Hull Thornless’ and ‘Thornfree’ endosperm callus proliferation occurred on different media.

Casein hydrolysate addition to the medium appeared essential for callus proliferation.
It occurred in 4 out of 8 media enriched with this compound while never occurred in the 20 media in which this compound was lacking.