Genetic diversity is essential for continued genetic improvement of crops. Genetically variable germplasms serve as a source of rare or unique alleles for introgression into elite cultivars to enhance their performance. However, identifying germplasms with alleles variant at a locus underlying phenotypic variation for a trait of interest is a challenge. Although, there are on-going studies to evaluate genetic diversity on several crops, the genetic diversity data generated from those studies has been accessible to the public only to a limited extent. At the Gramene database, a genetic diversity module (http://www.gramene.org/db/diversity/diversity_view), has been developed to collect, integrate, store and make publicly accessible the genetic diversity data generated on cereal crops. Currently, the database contains SSR, RFLP and SNP allelic data and passport descriptions for rice, maize and wheat germplasm accessions. It also holds phenotypic data on maize and rice germplasms including from QTL studies. Searches can be done for allelic variation across loci of a germplasm accession or at a locus across multiple germplasm accessions using germplasm accession number, accession name or marker/locus name. The Genomic Diversity and Phenotype Connection (GDPC) search tool also allows advanced search, integration and downloading of data from multiple experiments and databases.

Genetic data sources for rice are published papers, whereas maize and wheat data are obtained from the “Molecular and Functional Diversity of the Maize Genome” and “Haplotype Polymorphism in Polyploid Wheats and Their Diploid Ancestors” projects, respectively.

The database is updated 4 times a year.