Breeding Improved Varieties Of White Clover.

End of Project ReportWhite clover is one of the most nutritious species available in grassland/ruminant production systems. In association with grass, this species increases protein, mineral content, intake and nutrient value of the total forage. Because of its nitrogen fixing capacity, white clover has the potential to reduce, or in the case of organic systems, eliminate the need for inorganic nitrogen fertilizer on grazed grassland. Grassland-based animal production is a major part of the Irish agricultural economy, consequently any improvement in this legume has large potential benefit in this sector. The background, methodology, objectives and output of the current Teagasc, Oak Park white clover breeding programme are outlined. Five varieties have been released and are currently on Recommended Lists in Ireland and elsewhere. Aran, first released in 1981, has remained the highest yielding clover variety in UK trials, it is also widely grown in New Zealand, Australia and France as well as Ireland and UK. Avoca has shown very good yield and persistency under a range of managements and is widely used in Ireland and UK. Chieftain, the most recently released variety, has given 25% more clover yield than the control under lax defoliation (simulated grazing) management in UK Recommended List trials. In parallel with the breeding programme, research on nitrogen fixation and development of inbred lines in this species was undertaken. A brief summary of some of the results is included in this report.DLF-TRIFOLIU