Effective micropropagation of kale (Brassica oleracea convar. Acephala var. sabellica): one of the most important representatives of cruciferous crops

Kale (Brassica oleracea convar. acephala var. sabellica) is one of the oldest Brassica vegetable varieties with the highest nutritional value and stress resistance. This work aimed to establish an efficient kale micropropagation protocol. Shoot tips were used as explants during axillary shoots multiplication. The most effective cytokinin (6 and 10 shoots per explant after the 1st and 2nd passage, respectively) was 2.5 mg dm−3 6-benzylaminopurine. Rooting was the most effective on MS medium supplemented with 1.0 mg dm−3 indole-3-acetic acid (IAA; 95% rooted shoots). The highest survival rate during acclimatization to ex vitro conditions occurred when plantlets were planted in a soil and perlite mixture. No changes in DNA content were detected using flow cytometry. This paper additionally emphasizes problems associated with the abnormal development of some multiplied Brassicaceae shoots. Nevertheless, the results confirmed that kale micropropagation was successful without any phenotypic aberration.