Improved germination of threatened medicinal Prunus africana for better domestication: effects of temperature, growth regulators and salts

Abstract

Prunus africana is an endangered medicinal species and has been classified as a priority for domestication in Cameroon. However, the seeds rapidly lose their viability during storage at room temperature after 2–3 months. This study aimed to improve seed germination of P. africana by germinating at different temperatures (4 °C, 28 °C) using different concentrations of growth stimulators (sodium nitrate and gibberellic acid) and different concentrations of salts. P. africana seeds had 91.7% germination at 4 °C after 1 month of storage. Growth regulators considerably influenced germination after 6 months and reached 66.0% with 10 mM gibberellic acid and 100% with 10 mM sodium nitrate. Approximately three shoots per seed were developed, an indication of polyembryony. Histochemical analyses revealed the presence of protein-like bodies close to the embryo axis and accumulations of starch after 7 days of germination. After 14 days, amyloplasts and dark protein bodies of various sizes were observed. The outcome of this study will contribute to improve the germination of P. africana for better domestication and conservation.

Keywords

Conservation / Germination / Growth regulators / Histochemical analyses / Prunus africana / Temperature

References

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