A low-cost aeroponic phenotyping system for storage root development: unravelling the below-ground secrets of cassava (Manihot esculenta)

Selvaraj, Michael Gomez; Montoya-P, Maria Elker; Atanbori, John; French, Andrew P.; Pridmore, Tony

Abstract

© 2019 The Author(s). Background: Root and tuber crops are becoming more important for their high source of carbohydrates, next to cereals. Despite their commercial impact, there are significant knowledge gaps about the environmental and inherent regulation of storage root (SR) differentiation, due in part to the innate problems of studying storage roots and the lack of a suitable model system for monitoring storage root growth. The research presented here aimed to develop a reliable, low-cost effective system that enables the study of the factors influencing cassava storage root initiation and development. Results: We explored simple, low-cost systems for the study of storage root biology. An aeroponics system described here is ideal for real-time monitoring of storage root development (SRD), and this was further validated using hormone studies. Our aeroponics-based auxin studies revealed that storage root initiation and development are adaptive responses, which are significantly enhanced by the exogenous auxin supply. Field and histological experiments were also conducted to confirm the auxin effect found in the aeroponics system. We also developed a simple digital imaging platform to quantify storage root growth and development traits. Correlation analysis confirmed that image-based estimation can be a surrogate for manual root phenotyping for several key traits. Conclusions: The aeroponic system developed from this study is an effective tool for examining the root architecture of cassava during early SRD. The aeroponic system also provided novel insights into storage root formation by activating the auxin-dependent proliferation of secondary xylem parenchyma cells to induce the initial root thickening and bulking. The developed system can be of direct benefit to molecular biologists, breeders, and physiologists, allowing them to screen germplasm for root traits that correlate with improved economic traits.

Citation

Selvaraj, M. G., Montoya-P, M. E., Atanbori, J., French, A. P., & Pridmore, T. (2019). A low-cost aeroponic phenotyping system for storage root development: unravelling the below-ground secrets of cassava (Manihot esculenta). Plant Methods, 15(1), https://doi.org/10.1186/s13007-019-0517-6

• Journal Article Type: Article
• Acceptance Date: Oct 31, 2019
• Online Publication Date: Nov 9, 2019
• Publication Date: 2019-12
• Deposit Date: Nov 13, 2019
• Publicly Available Date: Nov 13, 2019
• Journal: Plant Methods
• Print ISSN: 1746-4811
• Electronic ISSN: 1746-4811
• Publisher: BioMed Central
• Peer Reviewed: Peer Reviewed
• Volume: 15
• Issue: 1
• DOI: https://doi.org/10.1186/s13007-019-0517-6
• Keywords: Aeroponics; Auxin; Cassava; Dripponics; Semi-aeroponic; Root bulking; Storage root; Tuber crops
• Public URL: https://hull-repository.worktribe.com/output/3135842
• Additional Information: Received: 16 April 2019; Accepted: 31 October 2019; First Online: 9 November 2019; : Not applicable.; : All authors agreed to publish this manuscript.; : The authors declare that they have no competing interests.