Variation of carbon and isotope natural abundances (δ15N and δ13C) of whole-plant sweet potato (Ipomoea batatas L.) subjected to prolonged water stress

Carla S S Gouveia; José F T Ganança; Jan Slaski; Vincent Lebot; Miguel Â A Pinheiro de Carvalho

doi:10.1016/j.jplph.2019.153052

Variation of carbon and isotope natural abundances (δ¹⁵N and δ¹³C) of whole-plant sweet potato (Ipomoea batatas L.) subjected to prolonged water stress

J Plant Physiol. 2019 Dec:243:153052. doi: 10.1016/j.jplph.2019.153052. Epub 2019 Oct 3.

Authors

Carla S S Gouveia¹, José F T Ganança², Jan Slaski³, Vincent Lebot⁴, Miguel Â A Pinheiro de Carvalho²

Affiliations

¹ ISOPlexis Genebank, University of Madeira, Campus da Penteada, 9020-105, Funchal, Madeira, Portugal. Electronic address: csgouveia@staff.uma.pt.
² ISOPlexis Genebank, University of Madeira, Campus da Penteada, 9020-105, Funchal, Madeira, Portugal.
³ ISOPlexis Genebank, University of Madeira, Campus da Penteada, 9020-105, Funchal, Madeira, Portugal; Ecosystems and Plant Sciences, InnoTech Alberta, PO Bag 4000, Hwy 16A & 75 Street, Vegreville, Alberta, Canada.
⁴ CIRAD-BIOS, PO Box 946, Port Vila, Vanuatu.

PMID: 31689580
DOI: 10.1016/j.jplph.2019.153052

Abstract

Sweet potato (Ipomoea batatas L.) is an important crop in the world, cultivated in temperate climates under low inputs. Drought changes the plant biomass allocation, together with the carbon and nitrogen isotopic composition (δ¹³C and δ¹⁵N), whose changes are faintly known in sweet potato crops. Here, we show the biomass allocation of eight sweet potato accessions submitted to drought during 3 months, using the δ¹³C, δ15N, carbon isotope discrimination (Δ¹³C), total carbon (TC) and water use efficiency (WUE) traits. The tolerant accessions had improved WUE, with higher TPB and TC. Storage roots and shoots had a heavier δ¹³C content under drought stress, with greater ¹³C fixation in roots. The Δ¹³C did not show a significant association with WUE. The δ15N values indicated a generalised N reallocation between whole-plant organs under drought, as a physiological integrator of response to environmental stress. This information can aid the selection of traits to be used in sweet potato breeding programs, to adapt this crop to climate change.

Keywords: Biomass allocation; Drought physiological integrator; Drought stress; Ipomoea batatas; Stable isotope abundances.

MeSH terms

Biomass*
Carbon / metabolism*
Carbon Isotopes / analysis*
Droughts*
Ipomoea batatas / physiology*
Nitrogen Radioisotopes / analysis*

Substances

Carbon Isotopes
Nitrogen Radioisotopes
Nitrogen-13
Carbon
Carbon-13