Demucilaging Freshly Stored Seeds of Cocoa (Theobroma cacao L.) Improves Seedling Emergence and Growth

Abstract

Fresh seeds of cocoa (Theobroma cacao L.) are covered by a large amount of mucilage, which plays important ecological roles. However, for stored seeds, mucilage can adversely affect germination. This study investigated the effect of mucilage removal (demucilaging) and seed storage of freshly extracted cocoa seeds on seedling emergence and growth. The study showed that demucilaging cocoa seeds confers several advantages over mucilage intact seeds provided the seeds have been stored for at least three days before sowing. Demucilaging increased germination rate (T50) and percentage germination and presence of mucilage increased days to seedling emergence and cessation of germination when seeds were stored for over two days. For up to 21 days of seed storage, there was generally no difference in many traits for demucilaged seeds. Demucilaged seeds had 80–100% germination after 21 days of storage, and rate of germination increased with increasing duration of seed storage. Intact mucilage seeds maintained 80–100% germination for only 2 days after seed extraction and rate of germination decreased with increasing seed storage duration. We conclude that (i) if seeds are sown on the day of extraction demucilaging before sowing would be superfluous and (ii) demucilaging and storage can provide advantages to smallholder farmers when environmental or socioeconomic conditions preclude immediate sowing.