Evidence map›Paper›PMID 20054521›Full record

SynthesisTAG. Theoretical and applied genetics. Theoretische und angewandte Genetik2010

Genetic diversity trends in twentieth century crop cultivars: a meta analysis.

Mark van de Wouw, Theo van Hintum, Chris Kik, Rob van Treuren, Bert Visser

Abstract readHistorical ArticleMeta-Analysis
In one paragraph

Synthesis in TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik, 2010. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 50 papers, 2 of them syntheses that pooled it.

0numbers the graph read from it
0cells of the map it votes in
50citing papers in PubMed, 2 pooled it
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

50 citing papers in PubMed, 2 syntheses or guidelines pooled it.

  1. Mapping the characterization landscape ofFrontiers in plant science · 2026
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  5. An Integrated Study of Ramie (Ecology and evolution · 2025
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  6. Review
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  8. Elucidating the Genetic Relationships on the Original Old SicilianInternational journal of molecular sciences · 2022
    Article
  9. Article
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  12. Genetic diversity and disease: The past, present, and future of an old idea.Evolution; international journal of organic evolution · 2022
    Article
  13. Article
  14. Article
  15. Article
  16. Article
  17. Crop adaptation to climate change as a consequence of long-term breeding.TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik · 2021
    Review
  18. Article
  19. Article
  20. Article
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

5 authors.

Mark van de WouwCentre for Genetic Resources, The Netherlands, Wageningen University and Research Centre, Wageningen, The Netherlands. markvandewouw@yahoo.co.uk
Theo van Hintum
Chris Kik
Rob van Treuren
Bert Visser

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

In recent years, an increasing number of papers has been published on the genetic diversity trends in crop cultivars released in the last century using a variety of molecular techniques. No clear general trends in diversity have emerged from these studies. Meta analytical techniques, using a study weight adapted for use with diversity indices, were applied to analyze these studies. In the meta analysis, 44 published papers were used, addressing diversity trends in released crop varieties in the twentieth century for eight different field crops, wheat being the most represented. The meta analysis demonstrated that overall in the long run no substantial reduction in the regional diversity of crop varieties released by plant breeders has taken place. A significant reduction of 6% in diversity in the 1960s as compared with the diversity in the 1950s was observed. Indications are that after the 1960s and 1970s breeders have been able to again increase the diversity in released varieties. Thus, a gradual narrowing of the genetic base of the varieties released by breeders could not be observed. Separate analyses for wheat and the group of other field crops and separate analyses on the basis of regions all showed similar trends in diversity.

Indexed as

Genetic VariationConfidence IntervalsCrops, AgriculturalHistory, 20th CenturyTriticum

Identifiers

PMID20054521
PMCPMC2839474

What OpenQuestion holds

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LicenceCC BY-NC
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Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.