Identification of candidate miRNAs related in storage root development of sweet potato by high throughput sequencing

Sweet potato is a tuberous root crop with strong environmental stress resistance. It is beneficial to study its storage root formation and stress responses to identify sweet potato stress- and storage-root-thickening-related regulators. Here, six conserved miRNAs (miR156g, miR157d, miR158a-3p, miR161.1, miR167d and miR397a) and six novel miRNAs (novel 104, novel 120, novel 140, novel 214, novel 359 and novel 522) were isolated and characterized in sweet potato. Tissue-specific expression patterns suggested that miR156g, miR157d, miR158a-3p, miR167d, novel 359 and novel 522 exhibited high expression in fibrous roots or storage roots and were all upregulated in response to storage-root-related hormones (indole acetic acid, IAA; zeaxanthin, ZT; abscisic acid, ABA; and gibberellin, GAs). The expression of miR156g, miR158a-3p, miR167d, novel 120 and novel 214 was induced or reduced dramatically by salt, dehydration and cold or heat stresses. Moreover, these miRNAs were all upregulated by ABA, a crucial hormone modulator in regulating abiotic stresses. Additionally, the potential targets of the twelve miRNAs were predicted and analyzed. Above all, these results indicated that these miRNAs might play roles in storage root development and/or stress responses in sweet potato as well as provided valuable information for the further investigation of the roles of miRNA in storage root development and stress responses.

Download Full-text

Compensation Response of Drip-irrigated Sugar Beets (Beta vulgaris L.) to Different Water Deficits during Storage Root Development

ACTA AGRONOMICA SINICA ◽

10.3724/sp.j.1006.2016.01727 ◽

2016 ◽

Vol 42 (11) ◽

pp. 1727

Author(s):

Yang-Yang LI ◽

Cong FEI ◽

Jing CUI ◽

Kai-Yong WANG ◽

Fu-Yu MA ◽

...

Keyword(s):

Beta Vulgaris ◽

Root Development ◽

Storage Root ◽

Sugar Beets ◽

Water Deficits ◽

Storage Root Development

Download Full-text

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

Plant Methods ◽

10.1186/s13007-019-0517-6 ◽

2019 ◽

Vol 15 (1) ◽

Cited By ~ 4

Author(s):

Michael Gomez Selvaraj ◽

Maria Elker Montoya-P ◽

John Atanbori ◽

Andrew P. French ◽

Tony Pridmore

Keyword(s):

Root Growth ◽

Root Development ◽

Low Cost ◽

Root Traits ◽

Suitable Model ◽

Root Initiation ◽

Storage Root ◽

Economic Traits ◽

Storage Roots ◽

Storage Root Development

Abstract 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.

Download Full-text

Sweetpotato root development influences susceptibility to black rot caused by the fungal pathogen Ceratocystis fimbriata

Phytopathology ◽

10.1094/phyto-12-20-0541-r ◽

2021 ◽

Author(s):

Camilo Humberto Parada Rojas ◽

Kenneth Pecota ◽

Christie Almeyda ◽

G. Craig Yencho ◽

Lina Quesada-Ocampo

Keyword(s):

Root Development ◽

Disease Incidence ◽

Black Rot ◽

Wild Relative ◽

Storage Root ◽

Storage Roots ◽

Ceratocystis Fimbriata ◽

Breeding Lines ◽

Below Ground ◽

Storage Root Development

Black rot of sweetpotato caused by Ceratocystis fimbriata, is an important reemerging disease threatening sweetpotato production in the United States. This study assessed disease susceptibility of the storage root surface, storage root cambium, and slips (vine cuttings) of 48 sweetpotato cultivars, advanced breeding lines, and wild relative accessions. We also characterized the effect of storage root development on susceptibility to C. fimbriata. None of the cultivars examined at the storage root level were resistant, with most cultivars exhibiting similar levels of susceptibility. In storage roots, Jewel and Covington were the least susceptible and significantly different from White Bonita, the most susceptible cultivar. In the slip, significant differences in disease incidence were observed for above and below ground plant structures among cultivars, advanced breeding lines, and wild relative accessions. Burgundy and Ipomoea littoralis displayed less below ground disease incidence as compared to NASPOT 8, Sunnyside and LSU-417, the most susceptible cultivars. Correlation of black rot susceptibility between storage roots and slips was not significant, suggesting that slip assays are not useful to predict resistance in storage roots. Immature, early developing storage roots were comparatively more susceptible than older, fully developed storage roots. The high significant correlation between storage root cross-section area and cross-sectional lesion ratio suggests the presence of an unfavorable environment for C. fimbriata as the storage root develops. Incorporating applications of effective fungicides at transplanting and during early storage root development when sweetpotato tissues are most susceptible to black rot infection may improve disease management efforts.

Download Full-text