| Title |
Genetic diversity trends in twentieth century crop cultivars: a meta analysis
|
|---|---|
| Published in |
Theoretical and Applied Genetics, January 2010
|
| DOI | 10.1007/s00122-009-1252-6 |
| Pubmed ID | |
| Authors |
Mark van de Wouw, Theo van Hintum, Chris Kik, Rob van Treuren, Bert Visser |
| 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. |
X Demographics
The data shown below were collected from the profiles of 44 X users who shared this research output. Click here to find out more about how the information was compiled.
Geographical breakdown
| Country | Count | As % |
|---|---|---|
| United States | 15 | 34% |
| Canada | 3 | 7% |
| United Kingdom | 2 | 5% |
| Kenya | 1 | 2% |
| Mexico | 1 | 2% |
| Honduras | 1 | 2% |
| Bolivia, Plurinational State of | 1 | 2% |
| Norway | 1 | 2% |
| Australia | 1 | 2% |
| Other | 2 | 5% |
| Unknown | 16 | 36% |
Demographic breakdown
| Type | Count | As % |
|---|---|---|
| Members of the public | 27 | 61% |
| Scientists | 16 | 36% |
| Practitioners (doctors, other healthcare professionals) | 1 | 2% |
Mendeley readers
The data shown below were compiled from readership statistics for 302 Mendeley readers of this research output. Click here to see the associated Mendeley record.
Geographical breakdown
| Country | Count | As % |
|---|---|---|
| Italy | 3 | <1% |
| Germany | 2 | <1% |
| Switzerland | 2 | <1% |
| Indonesia | 2 | <1% |
| United Kingdom | 2 | <1% |
| Philippines | 2 | <1% |
| France | 2 | <1% |
| United States | 2 | <1% |
| Peru | 2 | <1% |
| Other | 12 | 4% |
| Unknown | 271 | 90% |
Demographic breakdown
| Readers by professional status | Count | As % |
|---|---|---|
| Researcher | 88 | 29% |
| Student > Ph. D. Student | 60 | 20% |
| Student > Master | 20 | 7% |
| Student > Bachelor | 20 | 7% |
| Professor | 16 | 5% |
| Other | 62 | 21% |
| Unknown | 36 | 12% |
| Readers by discipline | Count | As % |
|---|---|---|
| Agricultural and Biological Sciences | 185 | 61% |
| Environmental Science | 20 | 7% |
| Biochemistry, Genetics and Molecular Biology | 19 | 6% |
| Social Sciences | 5 | 2% |
| Economics, Econometrics and Finance | 3 | <1% |
| Other | 19 | 6% |
| Unknown | 51 | 17% |
Attention Score in Context
This research output has an Altmetric Attention Score of 73. This is our high-level measure of the quality and quantity of online attention that it has received. This Attention Score, as well as the ranking and number of research outputs shown below, was calculated when the research output was last mentioned on 22 December 2022.
All research outputs
#550,399
of 24,330,936 outputs
Outputs from Theoretical and Applied Genetics
#9
of 3,649 outputs
Outputs of similar age
#1,916
of 171,611 outputs
Outputs of similar age from Theoretical and Applied Genetics
#2
of 15 outputs
Altmetric has tracked 24,330,936 research outputs across all sources so far. Compared to these this one has done particularly well and is in the 97th percentile: it's in the top 5% of all research outputs ever tracked by Altmetric.
So far Altmetric has tracked 3,649 research outputs from this source. They receive a mean Attention Score of 5.0. This one has done particularly well, scoring higher than 99% of its peers.
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We're also able to compare this research output to 15 others from the same source and published within six weeks on either side of this one. This one has done particularly well, scoring higher than 93% of its contemporaries.