Rooting plasticity in wild and cultivated Andean Chenopodium species under soil water deficit
Background and aims
Rooting plasticity is critical for plants exploiting patchy soil-water resources, but empirical evidence remains controversial due to complex root/soil interactions in natural and agricultural environments. We compared cultivated and wild Chenopodium populations from distinct agroecological background to assess their rooting plasticity when exposed to contrasting wet-dry soil profiles in a controlled environment.
Four treatments of increasing dryness were applied during 6 weeks in plants of Chenopodium hircinum, Chenopodium pallidicaule and two ecotypes (wet- and dry-habitat) of Chenopodium quinoa grown in rhizotrons. Root system architecture and growth were sequentially mapped. At the end of the experiment, plant and root morphological traits and dry biomass were measured.
Contrary to the other two species, C. quinoa showed accelerated taproot growth in dry soil conditions. The dry-habitat C. quinoa ecotype showed consistently higher plant traits related to longer, coarser, and more numerous root segments which give it a faster taproot growth and sustained root branching at depth in dry soil.
High rooting plasticity confers the advantage of fast root elongation and deep soil exploration under soil water deficit. Variation in intrinsic root traits and plastic responses among Chenopodium populations controls their root foraging capacity facing patchy soil-water resources.
KeywordsChenopodium quinoa C. hircinum C. pallidicaule Root architecture Rhizotron Natural and human selection
This research was funded by a PhD grant of the “Capital Humano Avanzado” programme of CONICYT (Chile), by the ANR (Agence Nationale de la Recherche—The French National Research Agency, project ANR-06-PADD-011, EQUECO), and the collaborative program 2012-PCCI 12051 "Desarrollo de una perspectiva socioecológica para un rubro prometedor: la quínoa sostenible en Chile" between CONICYT (Chile) and IRD (France). We thank the staff of the Plateforme des Terrains d’Expériences and the Plateforme d’Analyses Chimiques en Écologie, technical facilities of the Labex CeMEB (ANR-10-LABX-0004-CeMEB) where the plants were grown and the root analyses done. We are most grateful to Felix Mamani Reynoso and Alejandro Bonifacio (Universidad Mayor de San Andrés, La Paz, Bolivia) for kindly providing the seeds of C. pallidicaule and C. hircinum, to Dr. Jairo A. Palta (CSIRO, Australia) for his detailed remarks and suggestions about this manuscript and to the anonymous reviewers for their constructive comments.
- Ingram PA, Malamy JE (2010) Root system architecture. In: Kader J-C, Delseny M (eds) Advances in botanical research. Elsevier Academic Press, Burlington, Academic PressGoogle Scholar
- King MJ, Bush LP (1985) Growth and water use of tall fescue as influenced by several soil drying cycles. Agron J 77. https://doi.org/10.2134/agronj1985.00021962007700010001x
- Kramer PJ, Boyer JS (1995) Water relations of plants and soils. Academic Press, San DiegoGoogle Scholar
- National Research Council (1989) Lost crops of the Incas: little-known plants of the Andes with promise for worldwide cultivation. National Academy Press, Washington, D.C.Google Scholar
- Osmont KS, Sibout R, Hardtke CS (2007) Hidden branches: developments in root system architecture. Annu Rev Plant Biol 58:93–113. https://doi.org/10.1146/annurev.arplant.58.032806.104006 CrossRefPubMedGoogle Scholar
- Pagès L, Vercambre G, Drouet J-L, Lecompte F, Collet C, Le Bot J (2004) Root Typ: a generic model to depict and analyse the root system architecture. Plant Soil 258:103–119. https://doi.org/10.1023/b:plso.0000016540.47134.03 CrossRefGoogle Scholar
- Palta J, Watt M (2009) Chapter 13 - Vigorous crop root systems: form and function for improving the capture of water and nutrients. In: Crop Physiology. Academic Press, San DiegoGoogle Scholar
- Rich SM, Wasson AP, Richards RA, Katore T, Prashar R, Chowdhary R, Saxena DC, Mamrutha HM, Zwart A, Misra SC, Sai Prasad SV, Chatrath R, Christopher J, Watt M (2016) Wheats developed for high yield on stored soil moisture have deep vigorous root systems. Funct Plant Biol 43:173–188. https://doi.org/10.1071/FP15182 CrossRefGoogle Scholar
- Sandhu N, Raman KA, Torres RO, Audebert A, Dardou A, Kumar A, Henry A (2016) Rice root architectural plasticity traits and genetic regions for adaptability to variable cultivation and stress conditions. Plant Physiol 171(2562). https://doi.org/10.1104/pp.16.00705
- Suralta RR, Kano-Nakata M, Niones JM, Inukai Y, Kameoka E, Tran TT, Menge D, Mitsuya S, Yamauchi A (2016) Root plasticity for maintenance of productivity under abiotic stressed soil environments in rice: progress and prospects. Field Crop Res. https://doi.org/10.1016/j.fcr.2016.06.023
- Tapia ME (2000) Mountain agrobiodiversity in Peru. Mt Res Dev 20:220–225. https://doi.org/10.1659/0276-4741(2000)020[0220:MAIP]2.0.CO;2Google Scholar
- Troll C (1968) Geo-ecology of the mountainous regions of the tropical americas. In: Troll C (ed) Colloquium Geographicum. UNESCO-LARC-IGU, MexicoGoogle Scholar