Autoria: SANTOS, I. R. I.; SALOMAO, A. N.

Resumo: Germination of Ipomoea cynanchifolia seeds after storage at different temperatures and scarification. Abstract ? Ipomoea cynanchifolia Meisn., Convolvulaceae, is a wild relative of Ipomoea batatas (L.) Lam. (sweet potato). In this study, seeds with 7.8% water content were stored in a germinator (25 °C), a freezer (-18 °C) and in liquid nitrogen (-196 °C) for seven days. After storage, seeds underwent a decontamination treatment for 15 min, followed by three rinses with sterile distilled water, and after that seeds were scarified, by means of a cut in the opposite pole to the hilum made with nail pliers. Non-scarified (control, ESC-) and scarified (ESC +) seeds were sown in Petri dishes between filter paper discs soaked with water equivalent to three times the mass of the discs, and taken to a growth room at 25 ± 2 °C, with a 12h photoperiod. Observations occurred daily and counts occurred at 3, 7, 15 and 30 days after sowing using botanic (radicle protrusion) or technological (formation of a normal seedling with a green hypocotyl, cotyledons and root) criteria. Regardless of the storage temperature, germination percentages of ESC- seeds were low, with highest percentage of germination (15%) for seeds stored at -196 °C. In contrast, germination percentages for ESC+ seeds were high, ranging from 97% to 100%. These results show the occurrence of dormancy in I. cynanchifolia seeds, the need for scarification to promote seed germination and seed tolerance to storage at temperatures below freezing.

Ano de publicação: 2019

Tipo de publicação: Folhetos

Unidade: Embrapa Recursos Genéticos e Biotecnologia

Palavras-chave: Criopreservação, Cryopreservation, Dormência, Escarificação