Developing enhanced breeding methodologies for oats for human health and nutrition (INNOVOAT)

The objectives of this project were three-fold. Firstly, to determine the effect of nitrogen (N) rate on selected modern winter oat varieties and provide information to farmers on the optimal N to use – for enhanced yield and grain quality and, ultimately, milling performance. Secondly, to use precisely developed genetic stocks, in which specific regions of the genome controlling key grain quality and yield related traits have been introgressed into a common genetic background, to identify the effect of specific QTL on grain quality, yield and agronomic performance in a range of environments. Thirdly, to communicate results and recommendations to stakeholders, academics and the public.

Results have revealed the large effect of the environment on grain yield and on all grain quality measures analysed, with a significant interaction between variety and environment. The winter oat variety Mascani was found to have the most stable grain quality across all treatments. Dissection of grain quality traits has revealed the importance of grain roundness on milling quality.

A series of QTL-NILs, in which key QTL for adaptive traits such as flowering time and height have been introgressed into either a Buffalo or Tardis background, were used to validate QTL identified in previous studies and to understand the physiological basis of these traits. The results have provided new insights into the interaction of height and flowering time genes on stem extension and heading date, and on grain quality. In the process, new genetic markers have been identified and shared with breeders to facilitate more efficient selection of these regions, along with understanding as to how traits are closely linked or pleiotropic to these QTL.

Detailed analysis of N response has identified that, although higher levels of N fertilisation increased grain yield over all varieties, there was a variety dependent positive response to increased N for kernel content and hullability, but a negative response of both specific weight and screenings. At high N, some varieties may have specific weights and screenings below milling specifications, despite meeting kernel content and hullability requirements, and having higher β-glucan content.

Results have been incorporated into the recent review of recommendations for farmers (RB209) on N applications in winter oats, although it was concluded that there was insufficient data to derive robust N recommendations for winter oats. This knowledge gap is now being addressed in the AHDB and industry-funded project ‘Optimising nitrogen rates and timings and sulphur in winter and spring oats for yield and milling quality’ (NoatS – 21140039). As varieties differed in the extent of response to N fertiliser, it is necessary to develop variety‐specific N management plans. This emphasises the importance of variety choice, as well as management strategies for specific cultivars. These findings highlight the complementary use of breeding and management in the production of milling oats.