Abstract
The Defra Pulse Crop Genetic Improvement Network (PCGIN) is a platform that serves the process of legume crop improvement in the UK. It establishes the route by which scientific resources, results and knowledge are delivered to breeders, producers and end users, providing a link between these groups and the research base to achieve added value for pulse crops. It provides resources, expertise and understanding that are drawn upon by both public and commercial sectors in breeding, analysis, and in the definition and improvement of product quality relating to both commercial and public goods. It promotes and executes the translation of genomic research tools to crop improvement, consistent with both the needs of UK industry, and Defra objectives relating to sustainable agriculture. Furthermore, it provides links with, and involvement in, European pulse crop research programmes. Pulse crops and Defra policy objectives: In the current environmental, political and economic context it is clear that the energy efficiency of agriculture will become increasingly important. Similarly greenhouse gas emissions from agriculture will need to be minimised. Nitrogen fertilizer is a major energy demand in agriculture and its production, transport and use are major contributors to N2O emissions. Crop diversification and lowering inputs are major drivers for sustainable agricultural policy. Pulse crops can contribute positively to these two policy goals because, as a consequence of biological nitrogen fixation, they require minimal inputs while acting as a very effective break crop in a cereal dominated rotation. Pulse crops therefore minimise the negative impact of both the application of nitrogen fertiliser and its production, through reducing the demand for nitrogen fertilizer for pulse and subsequent crops. To achieve the benefits of pulse crops, legumes need to fit within farmers’ economic model. A major cause of their limited contribution is farmers’ perception that these crops have erratic performance and that their end product value is variable. Yield potential of pulse crops is high but average yields are about half of the best achieved, and even the best UK yields fall short of their potential by about 25%. There are many causes for this, but efforts to improve yield consistency through genetics and breeding have the potential to achieve an increase in pulse production in the UK. Thus there is a need to make legume crops more attractive to farmers, and to increase the market value of their product. These two are the major strands of PCGIN activity. The first is being addressed through the improvement of crop performance and reliability, by establishing the genetic basis for agronomic traits such as standing ability, yield and disease. This will address the major problems in growing pulse crops, as defined by breeders and growers. Yield per se is a complex trait which, aside from the components attributable to plant architecture and disease, is likely to be genetically determined. Although commercial lines having greater resistance to lodging are available now for pea, there are no reliable genetic markers associated with this trait and the genetic complexity of the trait is not understood. Although genetic resistance markers have been defined for powdery mildew in pea, none has been described for downy mildew, a fungus that has a large impact in diminishing yield in pea and in faba bean. Additional disease problems exist for both pea and bean, although not all of these are a problem within the UK. Pulse crops are also an efficient source of plant-derived protein for food and animal feed. Increasing the market value of seed products will depend on genetic studies that define and underpin the traits that limit quality. For the high premium export markets available to pulse growers in the UK, visual traits are extremely important as quality determinants. Of these, colour stability can determine whether seeds reach export grade or are classified as lower value feed. For animal feed, improved digestibility of seed components is an important goal in minimising eutrophicating waste, while improving animal performance. In faba bean, a major problem affecting quality (and yield) has been posed by bruchid beetle attack in recent years. This and additional problems in faba bean have highlighted the need for basic genetic toolkit development in this species. Structure and activity of PCGIN: The PCGIN is managed by JIC, PGRO, NIAB and Defra, with ex officio input provided by the commercial sector. Core scientific research underpinning pulse crop genetics is performed jointly by the first three organisations in projects that combine phenotypic and performance character assessment with genetic tool development. Resources that are being developed within PCGIN for the study of agronomic and seed quality traits are based on consultation with stakeholders. PCGIN2 will build on resources developed in the first phase that will be used to establish the genetic basis for traits that are relevant to UK pulse breeding, farming and end-user industries. Stakeholder involvement has been instrumental in defining and prioritising traits, and in the choice of genotypes used to build populations for trait analysis. Inbred populations of pea will be used to study the inheritance of traits under field conditions and to define the inheritance of these traits, by building genetic maps. The principal traits will be yield, disease resistance and lodging. A basis for the study of genetics in field bean (Vicia faba) will be established, and genetic maps established for pulse crop species.
United Kingdom