Previously I described the compilation of a list of 517 contemporary Citation Classics in Plant Sciences (1992-2017) and tempted the reader with the prospect of revealing more about the authors, journals and organisations represented in these papers. So, as promised, here is some detail:
The list contained authors working in forty-six countries (Figure 1), representing over 500 different organisations. Authors working in the USA appeared on 242 (46.8%) of the papers and authors working in the United Kingdom and Germany appeared on 19.1% and 11.8% of the papers, respectively. French, Australian and Japanese organisations were also well represented. Chinese organisations appeared on only 1.2% of the papers, but it is widely believed that this number will increase greatly in the coming decades as the substantial investments made by China in plant and agricultural sciences reap their reward (OECD 2017, Science Alert 2018, Clarivate Analytics 2018). The organisations represented most frequently were the University of California, which provided authors for more than 8.3% of the papers, RIKEN, which provided authors for 4.4% of the papers, and CNRS, which provided authors for 4.3% of the papers. Cornell University, INRA, JIRCAS, USDA and the Max Planck Institutes were represented on 3.5% of the papers, and researchers from CSIRO appeared on 3.3% of the papers.
Previously, I mentioned my surprise that all but one of the ten most cited papers on the list had no more than two authors. I was doubly surprised that two-thirds of the Citation Classics published since 1992 had three or fewer authors and that 19.7% were works of single authors (Figure 2). So, I guess that the size of the collaboration did not matter in the past, and an insightful individual could make a key contribution to the development of a scientific field.
More than 200 authors had contributed to at least two papers on the list, and nineteen authors had contributed to five or more Citation Classics (Figure 3). Many of the latter were co-authors of several Citation Classics. For example, Kazuo Shinozaki collaborated with Kazuko Yamaguchi-Shinozaki on eighteen, Motoaki Seki on nine and Hiroshi Abe on five of their Citation Classics, Christine Foyer and Graham Noctor co-authored six Citation Classics, Gordon Cragg and David Newman co-authored five Citation Classics, Douglas and Pamela Soltis co-authored five Citation Classics, and Corné Pieterse and Leendert Van Loon co-authored four Citation Classics.
Most Citation Classics on the list were published in Plant Cell (82) and Annual Review of Plant Biology (or its predecessor Annual Review of Plant Physiology and Plant Molecular Biology, 74). Fifteen other journals had published ten or more Citation Classics: Plant Physiology (39), Plant Journal (33), Trends in Plant Science (30), New Phytologist (28), Journal of Experimental Botany (21), Current Opinion in Plant Biology (16), Plant Cell and Environment (15), Phytochemistry (13), Plant Molecular Biology (12), Annual Review of Phytopathology (11), Theoretical and Applied Genetics (11), Annals of Botany (10), Journal of Ecology (10), Journal of Natural Products (10) and Plant and Soil (10).
If anyone is wondering why Nature, Science and Proceedings of the National Academy of Sciences of The United States of America did not feature in the list, it is because Web of Science considers that these journals publish only “multidisciplinary” articles, which do not appear in a search using “SU=Plant Sciences”. There would surely be more Citation Classics in Plant Sciences since 1992 if relevant papers from these distinguished journals had been included in the analysis and a corresponding increase in the threshold number of citations required of a contemporary Citation Classic in this field. But, one has to start somewhere and know one’s limits.
When I compared the number of Citation Classics with the most recent Impact Factors (IFs) of the top 50 journals in the Web of Science category “Plant Sciences”, there appeared to be a positive relationship between the two, especially among journals established before 1992 (Figure 4). However, it was noticeable that some well-established journals with high IFs had published few Citation Classics, probably due to the transient popularity of the papers they publish. In addition, journals that were established more recently, even those with very high IF, had generally published few Citations Classics (purple and blue data), presumably because of the length of time it takes for a Citation Classic to accrue sufficient citations.
So, in conclusion:
- The list of contemporary Citation Classics in Plant Sciences is dominated by authors working in the USA, particularly at the University of California and Cornell University;
- Although most contemporary Citation Classics in Plant Sciences were authored by three or fewer authors, many of the researchers with the most papers on the list were co-authors on multiple contemporary Citation Classics;
- In general, there was a positive relationship between the number of Citations Classics published in a journal and Impact Factor of that journal.
I hope I’ll be able to tell you more about the popular topics of contemporary Citation Classics and predict some future Citation Classics in Plant Sciences in another article.