under slow‑growth conditions

Abstract – The objective of this work was to evaluate in vitro storage of Piper aduncum and P. hispidinervum under slow-growth conditions. Shoots were stored at low temperatures (10, 20 and 25°C), and the culture medium was supplemented with osmotic agents (sucrose and mannitol – at 1, 2 and 3%) and abiscisic acid – ABA (0, 0.5, 1.0, 2.0 and 3.0 mg L-1). After six-months of storage, shoots were evaluated for survival and regrowth. Low temperature at 20oC was effective for the in vitro conservation of P. aduncum and P. hispidinervum shoots. In vitro cultures maintained at 20oC on MS medium showed 100 % survival with slow-growth shoots. The presence of mannitol or ABA, in the culture medium, negatively affected shoot growth, which is evidenced by the low rate of recovered shoots. Index terms: ex situ conservation, germplasm bank, micropropagation. Conservação in vitro de Piper aduncum e Piper hispidinervum sob condições de crescimento lento Resumo – O objetivo deste trabalho foi avaliar a conservação in vitro de Piper aduncum e P. hispidinervum, em condições de crescimento lento. Os brotos foram armazenados a baixas temperaturas (10, 20 e 25ºC), e o meio de cultura foi suplementado com agentes osmóticos (sucrose e manitol – a 1, 2 e 3%) e ácido abcísico – ABA (0, 0,5, 1,0, 2,0 e 3,0 mg L-1). Após seis meses de armazenamentos os brotos foram avaliados quant