Outstanding Papers

Outstanding Papers


Outstanding Papers on Plant Genetic Resources

How the outstanding papers are selected: Each year, papers on plant genetic resources in Crop Science are reviewed from the previous calendar year. In 1999, for example, 1998 papers are eligible. An awards committee composed of at least 7 members selects the outstanding plant genetic resources papers by secret ballot. Reviewers identify outstanding papers based on scientific merit and innovation in the following areas: discovery of novel agronomic genes from exotic germplasm by classical or molecular methods, statistical or molecular methods for quantifying genetic diversity, methods to improve germplasm regeneration and maintenance, and new approaches in the study of genetic diversity. All C-8 papers are considered except germplasm registrations.  For further information see award guidelines -


M.L. Serrano-Serrano, R.H. Andueza-Noh, J. Martinez-Castillo, D.G. Debouck, and M.I. Chacon.  Evolution and Domestication of Lima Bean in Mexico:  Evidence from Ribosomal DNA.  Crop Sci 52:1698-1712 (2012).

P.D. Olivera, A. Badebo, S.S. Xu, D.L. Klindworth, and Y. Jin.  Resistance to Race TTKSK of Puccinia graminis f. sp. tritici in Emmer Wheat.  Crop Sci 52:2234-2242 (2012).


Patrick J. Brown, Sean Myles and Stephen Kresovich.  Genetic Support for Phenotype-based Racial Classification in Sorghum.  Crop Science 51:224-230.

Mauricio Parra-Quijano, José M. Iriondo, Elena Torres and Lucía De la Rosa.  Evaluation and Validation of Ecogeographical Core Collections using Phenotypic Data.  Crop Science 51:694-703.

Yunwei Zhang, Juan Zalapa, Andrew R. Jakubowski, David L. Price, Ananta Acharya, Yanling Wei, E. Charles Brummer, Shawn M. Kaeppler and Michael D. Casler.  Natural Hybrids and Gene Flow between Upland and Lowland Switchgrass.  Crop Science 51:2626-2641.


Division Paper WinnerCrop adaptation in on-farm management by natural and conscious selection: A case study with lentil.

Bernd Horneburg and Heiko C. Becker

In this “back to the future” paper, the authors chose three farms with very different soils to test whether crop seed managed on-farm could be a way to conserve plant genetic resources while at the same time benefiting from their use, and enhancing biodiversity of the crop. The seeds selected for two to four years on each farm were superior in yield on that farm, compared to seeds selected at other locations. This showed that on-farm selection can create differences between seed sources (biodiversity), and that the differences can be positive and useful. Three different methods of selection, differing in several ways including the amount of time required to manage each one, were used on each farm. The authors recommend the simplest method, natural selection, as being a cost–efficient method for maintaining crop genetic diversity between farms.

Crop Sci. 2008 48: 203-212

Climatic adaptation and ecological descriptors of 42 Mexican Maize Races
José Ariel Ruiz Corral,* Noé Durán Puga, José de Jesús Sánchez González, José Ron Parra, Diego Raymundo González Eguiarte, J.B. Holland, and Guillermo Medina García
A group of seven Mexican authors and one U.S. author used geographic information system (GIS) data to study adaptation of different races of maize (corn).   They were looking for patterns of variation that might indicate genetic adaptation to extreme environments. The authors found that maize has a wider range than its closest wild relative, indicating that cultivated maize has evolved adaptability beyond the range of conditions in which it was first domesticated. They found a number of corn races in areas with that were extreme for low or high rainfall, or hot or cold temperatures. One race, Tuxpeño, was more widely adapted than any other. The greatest numbers of distinct maize races are found in temperate subtropical environments that are semi-arid or almost semi-arid. This information is important to guide collection and conservation of maize genetic resources, and to inform plant breeders about where to look for useful genes. 
Crop Sci. 2008 48: 1502-1512
Global genetic diversity of the perennial ryegrass fungal endophyte Neotyphodium lolii
Eline van Zijll de Jong, Mark P. Dobrowolski, Nathaniel R. Bannan, Alan V. Stewart, Kevin F. Smith,  Germán C. Spangenberg, and John W. Forster*
Perennial ryegrass is a nutritious pasture grass that is important in New Zealand and Australia. The interiors of ryegrass leaves are colonized by a fungus (an endophyte) that helps the plant grow and survive, especially when there is water deficiency or low soil fertility. However, the fungus also produces alkaloid compounds that are toxic to grazing animals. There is variation in ryegrass growth and toxicity. These authors wondered if the variation was due, not only to the genes in the ryegrass, but also to the genes of the fungal endophyte. They found that the genotype of the fungal endophyte does contribute to variation among different endophyte/ryegrass genotype combinations. They believe that molecular markers will make it possible to select for the best endophytes just as we now select for the best ryegrass, and to create combinations that favor both strong plant growth and low toxicity to grazers.  
Crop Sci. 2008 48: 1487-1501


Analysis of the Lr34/Yr18 rust resistance region in wheat germplasm
James A. Kolmer, Ravi P. Singh, David F. Garvin, Libby Viccars, Harinder M. William, Julio Huerta-Espino, Francis C. Ogbonnaya, Harsh Raman, Simon Orford, Harbans S. Bariana, and Evans S. Lagudah*
A gene originally detected in an Italian wheat variety has conferred resistance to multiple plant diseases for over a century. Selecting for the gene is expensive and slow because it can only be detected in the field; inexpensive greenhouse screenings of many thousands of seedlings cannot be used, because the resistance conferred by the gene is only effective in adult plant stages. An international team of 11 researchers tested a molecular marker to see if the marker could identify the gene in a wide range of types of wheat. Every time the marker was detected, the multiple resistance gene was also present. This information will make it easier, faster, and less expensive to breed wheat varieties with this gene.
Crop Sci. 2008 48: 1841-11852

B.K. Cornelious and C.H. Sneller. Yield and Molecular Diversity of Soybean Lines Derived from Crosses of Northern and Southern Elite Parents. Crop Sci 42: 642-647.

James G. Gethi, Joanne A. Labate, Kendall R. Lamkey, Margaret E. Smith, and Stephen Kresovich. SSR Variation in Important U.S. Maize Inbred Lines. Crop Sci 42(3): 951-957.

M. Smale, M.P. Reynolds, M. Warburton, B. Skovmand, R. Trethowan , R.P. Singh, I. Ortiz-Monasterio, and J. Crossa. Dimensions of Diversity in Modern Spring Bread Wheat in Developing Countries from 1965. Crop Sci 42(6): 1766-1779.

Philip Pardey, Bonwoo Koo, Brain Wright, Eric Van Dusen, Bent Skovmand, and Suketoshi Taba, Costing the conservation of genetic resources: CIMMYT's ex situ maize and wheat collection 41:1286-1299

Stephanie L. Greene and Brad Morris, The case for multiple-use plant germplasm collections and a strategy for implementation 41:886-892;

Jeff Steiner, Paul Beuselinck, Stephanie L. Greene, J. Kamm, Joseph Kirkbride, Craig Roberts, A description and interpretation of the NPGS birdsfoot trefoil core subset collection 41:1968-1980.

S. Liu (New Mexico State Univ.), R.G. Cantrell (Cotton, Inc.), J.C. McCarty, Jr.(USDA-ARS) and J. McD. Stewart (Univ. of Arkansas), Crop Science 40(5):1459-1469 demonstrated that all backcrosses are not equal in cotton. Many exotic cotton resources have been converted, through backcrossing, to an appropriate maturity for field testing in the USA. Using SSR DNA markers, the authors showed that some of these backcross-derived stocks carry much less of the original exotic DNA than others. They explained the potential negative impact on breeding and research, and then showed how to use the DNA marker information efficiently to offset the problem.

S. Beebe (CIAT, Colombia), P.W. Skroch (Univ. of Wisconsin), J. Tohme (CIAT), M.C. Duque (CIAT), F. Pedraza (CIAT), and J. Nienhuis (Univ. of Wisconsin), Crop Science 40(1):264-273 used RAPD DNA markers to show that Middle American germplasm of common bean is more complex than previously thought, and contains diversity that remains to be explored for its practical value.

J. Franco (ISEI, Mexico), J. Crossa (CIMMYT, Mexico), J. Villasenor (ISEI), A. Castillo (ISEI), S. Taba (CIMMYT), and S.A. Eberhart (USDA-ARS), Crop Science 39(1): 259-267 developed and tested a statistical method for developing core subsets from a large maize germplasm collection. This new approach encompassed hard-to-use qualitative traits as well as the standard quantitative phenotypic data in the statistical analysis.

D.Z. Skinner (USDA-ARS), G.R. Bauchan (USDA-ARS), G. Auricht (South Australian Research & Development Inst.), and S. Hughes (South Australian Research & Development Inst.), Crop Science 39(4): 1237-1242. Developing core collections from large germplasm banks (i.e., those with more than 10,000 accessions) can be difficult using standard multivariate statistical programs. The authors developed a short-cut statistical approach which, when combined with passport data, produced a representative core collection using only a fraction of the computing capability normally needed.

R.C. Johnson (USDA-ARS), Crop Science 38(3):851-857, showed that poor regeneration methods can harm the genetic structure of annual ryegrass populations in the national collection and proposed methods to solve this problem.

J. Villand, P.W. Skroch (Univ. of Wisconsin), T. Lai, P. Hanson, C.G. Kuo (Asian Vegetable Research Center, Taiwan), and J. Nienhuis (Univ. of Wisconsin), Crop Science 38(5):1339-1347, tested Vavilov's theory that crop diversity is related to center of origin using DNA marker analysis of Old World and New World tomato collections. They found that, contrary to traditional theory, Old World tomato accessions possessed a high level of diversity for commercial breeding.

M. A. Johns (Northern Illinois Univ.), P. W. Skroch, J. Nienhuis (Univ. of Wisonsin), P. Hinrichsen , G. Bascur, and C. Munoz-Schick (Instituto de Investigaciones Agropecuarias, Chile) Crop Sci. 37(2):605-613, charcterized genetic diversity in common bean by successfully using RAPD markers to assign Chilean landraces to Andean and Mesoamerican gene pools.

J. Franco (ISEI, Mexico), J. Crossa (CIMMYT, Mexico), Jose Villasenor (ISEI) S. Taba (CIMMYT) and S. A. Eberhart (USDA-ARS), Crop Sci. 37(3):972-980, compared an array of multivariate statistical analyses in the study of genetic diversity and identified those approaches which worked best for maize.

J. E. Epperson (Univ. of Georgia) , D. H. Pachico, and C. L. Guevara (CIAT, Colmbia),Crop Sci. 37(5):1641-1649, demonstrated that cassava plant genetic resources could be maintained more economically in vivo (the field) than in vitro (regeneration in the lab), providing valuable insight into management of germplasm collections.

P.R. Beuselinck and J.J. Steiner (USDA-ARS) and B. Li (Univ. of Missouri), Crop Sci. 36:179-185, showed that unlike the domesticated forage, Lotus corniculatus L., certain wild accessions produce rhizomes potentially important to the persistence of commercial types.

J.B. Holland (Iowa State Univ.), M.M. Goodman (North Carolina State Univ.), and F. Castillo-Gonzalez (Colegio de Postgraduados, Mexico), Crop Sci. 36:778-784, demonstrated that Latin American maize accessions possess favorable for genes for yield that apparently are absent from Corn Belt germplasm. This research signals the importance of exotic maize collections to U.S. breeding.

Joe Tohme, D. Orlando Gonzalez, Steve Beebe, and Myriam C. Duque (Center for Tropical Agriculture (CIAT), Colombia), Crop Sci. 36:1375-1384, demonstrated the utility of a relatively new DNA marker technique, AFLP analysis, in providing greater insight into the genetic structure of wild beans than had been possible previously. This work facilitates the use of wild bean collections in practical improvement programs.

D.G. Lohnes and A.F. Schmitthenner (Ohio State Univ.) and C.D. Nickell (Univ. of Illinois), Crop Sci. 36:1689-1692, examined the origin of Phytophthora resistance in exotic soybean accessions from the soybean ancestral center of diversity, China. Phytophthora is a major root disease of soybean. Based on the distribution of resistance in this collection, they were able to prioritize geographic areas of China for further exploration of Phytophthora resistance.