Background and Purpose

The project seeks to maintain and increase the value of oats as a profitable component of conventional and organic production for human and livestock consumption.

The previous work, which in the past has almost wholly used conventional selection, has collectively brought about significant advances which have opened doors to the greater acceptability of oats. New varieties have made oat growing easier and more profitable, and are largely responsible for the average national yield of oats being above that of barley in recent years. There is a need to build on these advances, through scientific approaches and shared investment through LINK combining the various, yet synergistic, industrial interests to exploit the real opportunities for oats as a crop, while focussing genetic improvement on differentiated quality markets.

Although conventional farmers, organic farmers, millers and poultry producers have different aims, there is also much in common in terms of the need for economic competitiveness, good agronomic and disease characteristics and the sharing of molecular markers. Therefore, the objectives of developing marker-assisted selection and using it and phenotypic selection to develop and test oats for the milling and poultry industry have been brought together in a single LINK project with strong industry pull. From the consumer viewpoint, the thrust of the project is to meet the needs of sustainable agriculture and to produce safe food.

The scientific justification is that the use of molecular markers in conjunction with phenotype assessments will allow more effective selection for more key traits (particularly those associated with differentiated quality) within the context of a real breeding programme. This innovative approach will be more effective than simply expanding the conventional breeding programme, through achieving better understanding of the inheritance of traits, through more effectively selecting for high trait expression using rapid and precise marker-assisted selection and by identifying and bringing together multiple interacting factors from genotypes of similar phenotypic value. The project will address a number of major issues such as cost and type of marker, population size, robustness and transferability of markers from other species and to diverse populations, and short- and medium term selection gains.

Brief summary of the results

The overall objective of OatLINK is to incorporate important traits underlying sustainable development of the oat crop through combining 'conventional' phenotypic selection with molecular marker technologies.

Specific Objectives of OatLINK were:

1. To develop new molecular markers, UK mapping populations and contrasting bulk segregants for use in marker-assisted selection (MAS) of important traits
2. Identify, incorporate, select and evaluate important traits for sustainable production and human consumption
3. To identify, incorporate, select and evaluate important traits for sustainable production and premium livestock feed
4. To identify, incorporate, select and evaluate important traits for organic production

Progress in meeting these objectives is summarised under each objective below.

1. To develop new molecular markers, UK mapping populations and contrasting bulk segregants for use in marker-assisted selection (MAS) of important traits

OatLINK has carried out extensive activities including marker assisted selection, construction of linkage maps, development of new molecular markers and phenotyping methodologies. Major achievements are as follows:

• Over 340 new polymorphic molecular markers developed in this project applicable to oat lines in the breeding programme. (50). In addition, new oat microsatellite markers developed elsewhere (150) have been evaluated on a range of lines from the IBERS breeding programme. We are part of an international consortium that has developed DArT markers resulting in approximately 2000 DArT markers that show polymorphism in a panel of 200 cultivated oat varieties, over 300 of which display polymorphism between our winter oat mapping family parents, Buffalo and Tardis.
• Development of the first winter oat genetic linkage map with 570 loci mapped onto 32 linkage groups and correspondence of linkage groups with those of the reference map (Kanota x Ogle) established
• Replicated yield and quality trials have been conducted with the Buffalo x Tardis mapping family to dissect out the genetics of yield and its components and identify yield limiting factors in dwarf oats. For example, grain number per panicle showed a close correlation with yield in dwarf oats (but not in conventional height oats). QTL for a large number of traits have been identified using this population including for kernel content.
• Phenotyping of populations developed for specific traits completed (low lignin husk, beta- glucan and Matilda x Freja populations)
• Identification of markers associated with the dwarfing gene (dw6), components of height and yield, β-glucan content, oil content and naked character. Verification of marker-trait associations for dwarfing gene (dw6), components of height, oil content and naked character in a wider range of genetic backgrounds
• Selection of parents in the breeding programme based on allele composition at key loci associated with traits of interest

2. Identify, incorporate, select and evaluate important traits for sustainable production and human consumption

We have used conventional phenotypic selection together with the development of molecular markers (in 1 above) that allow precise and rapid selection for important traits. Significant progress has been made in the development of markers for β-glucan content and in the development of rapid screening methods for this important trait which will enable selection of this trait in the future breeding programmes. The population 02-177ACnIII has been grown in the field for two years and selected progeny from this population have been identified using markers and utilised in the winter oat crossing programme to obtain UK adapted winter oats which have higher levels of β-glucan. From 2004 to present we have completed over 110 successful crosses per year for winter oats and 60 for spring oats to produce oats which are environmentally sustainable and meet the millers requirements.

In conjunction with ADAS, field trials have been undertaken to further dissect the components of lodging resistance, a key attribute for the growers and millers who increasingly demand grain produced without use of plant growth regulators. Straw height is not the only critera to prevent lodging although shorter straw does usually reduce the risk of lodging. Straw stiffness and rooting also play an important role. Currently plant growth regulators are routinely used on oats, however the CEL RL data demonstrated that some of the shorter newer varieties such as Tardis, Brochan, Mascani and Balado suffer a yield penalty as a consequence. In addition some millers market oats as being PGR free so dwarf oats or lodging resistant oats fit very well into their requirements.

3. To identify, incorporate, select and evaluate important traits for sustainable production and premium livestock feed

• The poultry industry expressed the need for oats which are economically competitive and/or have high oil/energy without jeopardising protein and amino-acid content. Both naked and husked oats have been studied with the focus on increasing the oil content and hence the energy (ME) value. Development of markers for oil have been summarised under objective 1. Various crosses have been carried out to validate markers associated with oil; for example 06-153 was grown in the glasshouse in 2006-2007 and then in the field in 2007.
• Over the course of the project approximately 500 crosses have been carried out to develop naked oats for animal feed. In general the high oil sources are from North America material unadapted to UK conditions and which are agronomically poor. The development of a high oil oat in a good genetic background with good agronomic attributes has therefore been challenging. The variety Racoon was added to the national list in 2006. This has an oil content of 12-14% but is very tall (>140cm). The objective is a high oil short or dwarf naked oat which is high yielding. For example in 2007 we completed 97 crosses with naked oats, 45 of these crosses are designed to provide high oil dwarf oats. Over 4000 ex F3 lines have been assessed for oil with a range from 6-12% determined by NIR.
• An NIR calibration for oil and total N content has been developed based on the cold sohtex method enabling the rapid analysis of oil content. This is routinely used for the naked oats.
• In 2006-07 50 high oil lines (>10% oil by NIR) were tested for agronomic quality, and 17 continued for further study in 2008. We have also entered a high oil dwarf oat into NL trials in 2008-2009.
• We have obtained confirmation that increasing oil content increases the energy (ME) value of naked oats. Within OatLINK Roslin ME bioassays have been carried out on broilers. ME values were quantified in a range of genetic material in a number of experiments from 2004-2008. This included advanced lines selected for high oil content (naked and husked oats) in comparison with conventional husked oats and feed wheat as well as some feed wheat used by commercial feed compounders. Chemical analysis of the lines has also been undertaken to identify impact on ME.
• Several large scale poultry feeding trials have been conducted by Bernard Matthews. The impact of incorporating the high oil line Racoon in the feed ration on bird health and productivity and on lipid stability was quantified. Energy and oil values assigned to Racoon (15.3 MJ/kg and 12.2%) respectively were confirmed by the study and bird performance was maintained when Racoon was included in the ration at the different inclusion rates.

4. To identify, incorporate, select and evaluate important traits for organic production

• A key objective of OatLINK is to quantify the agronomic performance of oat varieties and advanced selection lines in organic systems. Experiments have been conducted by Organic Research Centre - Elm Farm at two sites (Wakelyns and Sheepdrove) during the course of the project. A number of winter oat varieties (husked and naked) and advanced selection lines have been grown in experiments that compared methods of establishment, sowing rate and yield of these oats as both the 1st and 2nd cereal in the organic rotation.
• The experiments confirmed the potential of oats as a cereal particularly suited to organic production with yields of > 7t ha achieved. One of the main conclusions from the work in 06/07 was the difference in disease levels and yield between varieties in both the 1st and 2nd year. The winter oat varieties Tardis and Mascani yielded 7.3t/ha and 7.1t/ha respectively as the 1st cereal and 6.6t/ha and 7.0t/ha as the 2nd cereal and yielded more than Brochan and Gerald. Tardis and Gerald were notably less productive as 2nd cereals. However, the reduction between the average yields of the naked oats in the first and second cereal experiments was larger at 19% than in the husked experiments (3%).
• An additional treatment included a mixture of the individual varieties. The mixture had 18% less disease than the average of its component varieties confirming data from 05/06, and yielded well as the best individual variety as a 1st and 2nd cereal. The naked oat Expression yielded 5t/ha as the 1st cereal but there was no significant advantage from the mixture over the individual varieties either in disease or yield.

Life Cycle Analysis

Life cycle assessments (LCA) were completed in accordance with (ISO, 1997) for UK arable feed crops used in the poultry sector and for the UK porridge oat production chain. It was found that oats have relatively less environmental impact compared to other arable feed crops per unit delivered avian feed energy and therefore offer a more sustainable feed source for the poultry industry, however further work is needed in terms of the avian mass balance under different feeding regimes. The LCA of the porridge oat production chain was completed to investigate the impact of plant varietal development to the sustainability of UK porridge production. It was found that varietal improvements associated with the "downstream" cooking process were most influential across the majority of impact categories investigated. Furthermore traits relevant to the agricultural stage were especially important in the production chain, in particular, improvements in yield and nitrogen use efficiency correlated to a substantial reduction in the ecological footprint of porridge oats.