Register      Login
Functional Plant Biology Functional Plant Biology Society
Plant function and evolutionary biology
RESEARCH FRONT

Partitioning of assimilates to deeper roots is associated with cooler canopies and increased yield under drought in wheat

Marta S. Lopes A B and Matthew P. Reynolds A
+ Author Affiliations
- Author Affiliations

A CIMMYT, Int. Apdo. Postal 6-641, 06600 México, DF, Mexico.

B Corresponding author. Email: m.dasilva@cgiar.org

Functional Plant Biology 37(2) 147-156 https://doi.org/10.1071/FP09121
Submitted: 26 May 2009  Accepted: 5 November 2009   Published: 3 February 2010

Abstract

Dehydration avoidance through cooler canopy temperature (CT) has been shown to explain over 60% yield variation in a random progeny derived from a Seri/Babax cross. A near ‘isomorphic’ subset of Seri/Babax progeny and parents encompassing a restricted range of height and phenology were used for detailed characterisation of drought-adaptive trait expression under contrasting water regimes. Under drought, five of the six progeny out yielded the best parent Babax by up to 35%. The main physiological attributes associated with drought adaptation were increased root dry weight at depth, transpiration rate – evidenced by grain carbon isotope discrimination (Δ13C) – grain filling duration and decreased CT during grain filling. Furthermore, increased root mass at depth was associated with reduced levels of stem water soluble carbohydrates (WSC) when comparing genotypes. It is concluded that differences in rooting depth expressed among iso-morphic wheat sister lines explains superior adaptation to drought. These effects can be detected in season using remote sensing. In addition, the data suggest that accumulation of stem carbohydrates and deep rooting may be two alternative strategies for adapting to drought stress, the latter being beneficial where water is available at depth.

Additional keywords: adaptation, canopy temperature, carbon isotope discrimination, grain filling, water soluble carbohydrates.


Acknowledgements

Authors would like to thank Jose Luis Barrios and Israel Perazas for technical assistance with soil and root sampling, and Araceli Torres and Eugenio Perez for assistance with data and trial management respectively. The Australian Grains Research and Development Corporation (GRDC) are acknowledged for their financial support.


References


Araus JL, Slafer MP, Reynolds MP, Royo C (2002) Plant breeding and drought in C3 cereals: what should we breed for? Annals of Botany 89, 925–940.
Crossref | GoogleScholarGoogle Scholar | PubMed | [Verified 17 December 2009]

Condon AG, Richards RA, Rebetzke GJ, Farquhar GD (2004) Breeding for high water use efficiency. Journal of Experimental Botany 55, 2447–2460.
Crossref | GoogleScholarGoogle Scholar | CAS | PubMed | [Verified 17 December 2009]

Rebetzke GJ, van Herwaarden AF, Jenkins C, Weiss M, Lewis D, Ruuska S, Tabe L, Fettell NA, Richards RA (2008) Quantitative trait loci for water-soluble carbohydrates and associations with agronomic traits in wheat. Australian Journal of Agricultural Research 59, 891–905.
Crossref | GoogleScholarGoogle Scholar | CAS | [Verified 17 December 2009]

Sponchiado BN, White JW, Castillo JA, Jones PG (1989) Root growth of four common bean cultivars in relation to drought tolerance in environments with contrasting soil types. Experimental Agriculture 25, 249–257.
Crossref | GoogleScholarGoogle Scholar | open url image1

Vargas VJ, Crossa J, van Eeuwijk FA, Rami ME, Sayre K (1999) Using partial least squares regression, factorial regression, and AMMI models for interpreting genotype × environment interaction. Crop Science 39, 955–967. open url image1

Varshney RK, Graner A, Sorrells ME (2005) Genetic microsatellite markers in plants: features and applications. Trends in Biotechnology 23, 48–55.
Crossref | GoogleScholarGoogle Scholar | CAS | PubMed | open url image1

Voltas J, Romagosa I, Lafarga A, Armesto AP, Sombrero A, Araus JL (1999) Genotype by environment interaction for grain yield and carbon isotope discrimination of barley in Mediterranean Spain. Australian Journal of Agricultural Research 50, 1263–1271.
Crossref | GoogleScholarGoogle Scholar | open url image1

William HM, Trethowan R, Crosby-Galvan EM (2007) Wheat breeding assisted by markers: CIMMYT experience. Euphytica 157, 307–319.
Crossref | GoogleScholarGoogle Scholar | open url image1

Yem EW, Willis AJ (1954) The estimation of carbohydrates in plant extracts by anthrone. The Biochemical Journal 57, 508–514.
PubMed |
open url image1

Zadok JC, Chang TT, Konzak CF (1974) A decimal code for the growth stages of cereals. Weed Research 14, 415–421.
Crossref | GoogleScholarGoogle Scholar | open url image1