Resumo

MARTINEZ VILLEGAS, Ylvi María et al. In vitro culture of pitayo (Stenocereus stellatus [Pfeiffer] Riccobono). Rev. Chapingo Ser.Hortic [online]. 2011, vol.17, n.3, pp.95-105. ISSN 2007-4034.

The pitayo (Stenocereus stellatus) is a cactus native to Mexico that is prized for its fruits, which have unique organoleptic characteristics. It is propagated by cuttings taken from mature, usually wild plants, causing deforestation of natural areas. The objective of this study was to identify the optimum ctyokinin type and dose, plus sucrose concentration, to obtain a greater number of pitayo plants in vitro. Seeds from ripe fruits were used to obtain seedlings to initiate plant growth. For shoot multiplication, seedlings measuring 2 to 3 cm in height and divided into 1-cm sections were used. MS medium with 3 % sucrose was used. Three cytokinins (kinetin, 6-benzyladenine, and 2-isopentenyladenine) at five concentrations (2.2, 4.4, 8.8, 17.6 and 35.2 µM) were evaluated. For shoot growth, MS medium with sucrose (1, 2, 3, 4 and 5 %) was used. In plant acclimatization, the effect of the sucrose concentration used for in vitro shoot growth was assessed. It was found that the concentration of 17.6 µM 6-benzyladenine caused shoot formation in all explants, with eight shoots per explant. The shoots achieved the greatest height when grown in 3 and 4 % sucrose. Over 92 % of the plants transplanted to substrate survived acclimatization.

Palavras-chave : Cactaceae; cytokinins; tissue culture; plant multiplication; pitayo.