Abstract
Cassava, which produces edible starchy roots, is an important staple food for hundreds of millions of people in the tropics. Breeding of cassava is hampered by its poor flower production, flower abortion, and lack of reproductive prolificacy. The current work determined that ethylene signalling affects floral development in cassava and that the anti-ethylene plant growth regulator silver thiosulfate (STS) mitigates the effects of ethylene on flower development. STS did not affect the timing of flower initiation, but improved early inflorescence and flower development as well as flower longevity such that flower numbers were increased. STS did not affect shoot and storage root growth. Studies of silver accumulation and treatment localization support the hypothesis that the beneficial effects of STS are confined to tissues of the shoot apex. The most effective timing of application was before inflorescence appearance extending to post-flower appearance. Based on this work a recommended protocol for STS use was developed. This work has the potential to improve methods for enhancing cassava flower development in breeding nurseries and thereby synchronize flowering of desired parents and enable the production of abundant progeny of desired crosses.
Highlights
Cassava (Manihot esculenta Crantz) is a crop grown in tropical regions for its high-starch storage roots
Preliminary trials with a wide range of plant growth regulators (PGRs), including the cytokinin benzyl adenine, abscisic acid, jasmonic acid, and salicylic acid, indicated that the anti-ethylene agent silver thiosulfate (STS) was uniquely effective in improving cassava flowering (Supplementary Table S1; Hyde et al 2016)
We found 1-MCP to be ineffective in preliminary trials (Supplementary Table S1, worksheets PGR4 and 5)
Summary
Cassava (Manihot esculenta Crantz) is a crop grown in tropical regions for its high-starch storage roots. It ranks as the fourth largest source of energy in human diets in the tropics, after maize (Zea mays), rice (Oryza sativa) and wheat. An obstacle to cassava breeding is that many genotypes with valuable agronomic characteristics flower extremely late, have poor flower development, and abort before viable seed is produced (Adeyemo et al 2017, 2018; Ceballos et al 2017). Floral initiation occurs at the apical meristem and stimulates forking (production of 2–4 branches), thereby producing an axil where the flower structure develops; such forking occurs
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
