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  • Review Article
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Genetic approaches to crop improvement: responding to environmental and population changes

Nature Reviews Genetics volume 9, pages 444–457 (2008)Cite this article

Key Points

  • The identification of genes responsible for important agricultural traits has been mostly conducted by traditional molecular genetics and by QTL mapping. Recent and future advances in sequence technologies and polymorphism detection will facilitate more trait-oriented QTL studies.

  • Association mapping and selection screens are potentially useful approaches for future mapping studies and for allele mining. The development of applicable resources and studies of population structure will be important for the wider use of these methods.

  • Several genes that are responsible for major QTLs that control the size of grains or number of reproductive organs, thus affecting crop yields, have recently been revealed in rice. These genes encode factors that are involved in cell-division activity.

  • A gene that is responsible for submergence tolerance has been identified and suggested to control metabolic status during submergence.

  • Some genes required for tolerance to soil stresses have been found to encode transporters, the expression of which is spatially regulated. The underlying mechanisms for tolerance seem to be reasonably well conserved in plants.

  • To transfer genetic information conferring advantageous traits to a cultivar of preference, both non-transgenic (QTL-based) approaches and transgenic approaches (involving artificial design) can be used. Allele mining and gene pyramiding, by either hybridization or gene manipulation, will be important for crop improvement.

Abstract

Crop production is threatened by global climate change, and recent demands for crops to produce bio-fuels have started to affect the worldwide supply of some of the most important foods. How can we support a growing human population in such circumstances? One potential solution is the improvement of crops to increase yield from both irrigated and non-irrigated lands, and to create novel varieties that are more tolerant to environmental stresses. Recent progress has been made in the isolation and functional analyses of genes controlling yield and tolerance to abiotic stresses. In addition, promising new methods are being developed for identifying additional genes and variants of interest and putting these to practical use in crop improvement.

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Figure 1: QTL pyramiding.
Figure 2: Boron transporters.
Figure 3: Mechanistic models of salt tolerance.

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Acknowledgements

We thank M. Maeshima, T. Fujiwara, D. Saisho, M. Ashikari, and T. Hattori for useful suggestions.

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Authors and Affiliations

  1. Laboratory of Plant Cell Function, Bioscience and Biotechnology Center, Nagoya University, Chikusa, 464-8601, Nagoya, Japan

    Shin Takeda

  2. Laboratory of Plant Molecular Breeding, Bioscience and Biotechnology Center, Nagoya University, Chikusa, 464-8601, Nagoya, Japan

    Makoto Matsuoka

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DATABASES

Gramene 

ckx2

Gn1a

gs3

gw2

HKT7-A2

OsCKX2

sd1

Sub1

FURTHER INFORMATION

Shin Takeda's homepage

DOE Joint Genome Institute (JGI)

Maizesequence

Maizegenome

Panzea

Phytozome

RiceHapMap

Glossary

Quantitative trait locus

(QTL). A genetic locus controlling a complex trait (such as plant height or grain yield), which is typically affected by more than one gene and also by the environment.

Nearly isogenic line

(NIL). A line carrying an isolated homozygous segment that contains a target QTL of a parental chromosome; other than this QTL, the line has the other parental genetic background.

Ethylene response factor

(ERF). Refers to members of a subfamily of the AP2 transcription factor family, which is unique to the plant lineage. ERF subfamily proteins carry a domain that is conserved in ethylene-responsive element-binding proteins.

Major intrinsic proteins

(MIPs). A large protein family, the members of which act as channels in membranes to facilitate passive transport of small polar molecules such as water, glycerol and urea across the membrane.

Recombinant inbred line

(RIL). A progeny line carrying dispersed homozygous segments of a parental chromosome, formed after several selfed generations of an F2line.

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Takeda, S., Matsuoka, M. Genetic approaches to crop improvement: responding to environmental and population changes. Nat Rev Genet 9, 444–457 (2008). https://doi.org/10.1038/nrg2342

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