Designing ex-situ conservation strategies for seeds storage of Piper aduncum and P. hispidinervum through cryopreservation and low-temperature techniques

Abstract

Piper aduncum and Piper hispidinervum are species found primarily in the Amazon region, and have been highlighted by the fact that they contain, in their essential oils, significant amounts of dillapiol and safrole. The aim of this work was to assess the seed behavior of P. aduncum and P. hispidinervum and to develop strategies for medium-to long-term storage of the species at sub-zero and cryogenic temperatures. In the first experiment, seeds were desiccated and their water content was determined. Then, the seeds were kept at −20°C for up to 90 days. In the second experiment, seeds were stored for up to 24 h in liquid nitrogen (LN; −196°C), with and without the use of cryoprotectants. Finally, for assessing the efficiency of these techniques, seeds were stored at −20°C and in LN for up to 360 days. The germination rate was more than 90% for both species when stored at −20°C or LN, without compromising their viability and development. The results suggest that P. aduncum and P. hispidinervum have seeds with orthodox behavior, which can be stored for the medium to long term at sub-zero and cryogenic temperatures without the need for use of cryoprotectants. ARTICLE HISTORY

Tolerance to Desiccation and Cryopreservation of Seeds of Seven South American Ilex Species

“…Dehydration must be sufficient to avoid lethal intracellular freezing during cooling in LN but not so intense to induce extended desiccation injury. In optimal cases, no significant differences are observed in the survival rates of desiccated control and cryopreserved material (Da Silva et al, 2017;Endoh et al, 2018;Michalak et al, 2015b;Pammenter and Berjak, 1999).…”

Diaspore dispersal season influences root growth and seed traits, but not germination responses, of sympatric Piper species in a seasonal forest

“…2005; Silva et al . 2017) to desiccation have been recorded in Piper , which is a common occurrence among species with drupe‐type fruits (Hong & Ellis 1996). In the case of P. caldense and P. vicosanum , two explanations are possible.…”

“…The difference in seed viability over time among species may be related to variations in sensitivity to desiccation. Both species with seeds sensitive (recalcitrant; Garwood & Lighton 1990) and tolerant (orthodox; Daws et al 2005;Silva et al 2017) to desiccation have been recorded in Piper, which is a common occurrence among species with drupe-type fruits (Hong & Ellis 1996). In the case of P. caldense and P. vicosanum, two explanations are possible.…”