Reproductive biology, phenology, pollen viability and germinability in Kersting's groundnut (Macrotyloma geocarpum (Harms) Maréchal & Baudet, Fabaceae)

• Published in: South African journal of botany 2021-03, Vol.137, p.440-450
• Main Authors: Kafoutchoni, Konoutan Médard, Agoyi, Eric Etchikinto, Dassou, Gbèwonmèdéa Hospice, Sossou, Hospice Samson, Ayi, Sergino, Ahanhanzo Glèlè, Corneille, Adomou, Aristide Cossi, Yédomonhan, Hounnankpon, Agbangla, Clément, Assogbadjo, Achille Ephrem
• Format: Article
• Language: English
• Subjects: Anther dehiscence; Forced self-pollination; Pollen tube growth; Protogyny; Stigma receptivity; Style movement
• ISSN: 0254-6299; 1727-9321
• DOI: 10.1016/j.sajb.2020.11.015

•Kersting's groundnut flowers are bisexual and incompletely protogynous.•The flowers are of ‘pre-anthesis cleistogamous’ type.•Spontaneous self-pollination occurs in the flower, facilitated by style bending.•Emasculation may be done on one-day buds to prevent unwanted self-pollination. Knowledge gap on the reproductive biology of orphan crops is a major challenge to their cultivar development and genetic improvement. This study described the reproductive organs and phenology, assessed receptivity of stigma versus anther dehiscence, and examined pollen viability and germination in Kersting's groundnut. Experiments were conducted on nine morphotypes in a randomized complete block design with three replications in a screenhouse. Phenological observations were made on 1026 flower buds. Anther dehiscence was determined through microscopic observations while receptivity of the stigma was assessed using the hydrogen peroxide test. Pollen viability was assayed using histochemical staining. In vitro germination and pollen tube growth were assessed for up to 72h. Flowers were bisexual and incompletely protogynous, and spontaneous self-pollination was favoured by style bending. Flowering and fruiting were classified into six developmental stages each. Timing of all stages differed significantly (P