Crop Genetic Biodiversity with Special Reference to Oilseed Brassicas and Wild Allies: Conservation and Their Utilization

Abstract

Crop genetic resources and their wild relatives are likely to play a significant role in securing twenty-first-century food security. This is due to their potential use in plant breeding to produce crops which withstand adverse impacts of climate change, increasing scarcity of nutrients, water and other inputs and new insect pests and diseases. A high proportion of global food production is from a small number of scientifically bred crop varieties, with narrow genetic variation. This has resulted in loss of approximately 75% of global crop genetic diversity, as these new varieties replaced a much greater range of more genetically diverse, traditional crop varieties. In cultivation, wild plants have been transformed to make them more useful to humans. The genus represents a wide range of crops including oilseed, many vegetables and fodder crops and wild species. In some species this whole range of uses is present. The wide range of crops, species and applications cause Brassica genetic resources to be even more scattered over collections than other crops; no single collection holds the complete genetic diversity of Brassica. For an integrated approach of conserving genetic resource collections, networks on species or crops are essential. By networks’ collaboration, the tasks of long-term conservation of the genetic diversity and making it available to users can be more structured. Duplication of work can be avoided, and gaps in collections can be traced. For several crops there are international networks coordinated by the International Plant Genetic Resources Institute (IPGRI). For Brassica such a network does not exist (yet). Regeneration of Brassica is very costly and requires good storage conditions, in order to maintain the seed viability which is essential. It is also very important to avoid unnecessary duplicates. Consequently good and accessible information on the material in the collections is needed to trace these duplicates. An international central crop database with high-quality and highly accessible data would be of great help, for efficient utilization of material. For the wild Brassica species, in situ conservation is of high importance; the ex situ collections help to make a small part of the diversity readily accessible for utilization. In order to guarantee availability of Brassica germplasm to future generations, funding agencies, such as national governments, need to commit themselves to support coherent conservation programmes.