Selection for Increased Winter Production in Annual Ryegrass (Lolium multiflorum Lam).

Annual ryegrass (Lolium multiflorum Lam.) is a cool season annual bunchgrass possessing high palatability, forage quality, seedling vigor, persistence under close grazing and dry matter yield. It has a high growth rate during the reproductive phase in spring and relatively low during winter. Availability of standing forage for grazing in the southeastern USA is limited during the cooler months and improved winter growth would be a great benefit to cattle producers. The objective of this study was to evaluate of the progress from selection for increased dry matter winter production in annual ryegrass resulting from two cycles of phenotypic recurrent selection. Intermating 50 plants from the six top performers in Alabama Annual Ryegrass Trials formed the base population for the selection experiment. Bulk-harvested seed from the 1st synthetic generation was intermated again to create cycle 0 for the selection experiment. A 1200-plant nursery was established in late October of each year with plants spaced 90 cm in all directions. The nursery was subdivided into 48 blocks of 25 plants each (5 x 5 arrangement). Plants were harvested for dry matter determination 750 growing degree days (GDD) after transplanting, the best entries selected from each block were then intermated in isolation and bulk-harvested seed used for the next cycle. Replicated (r = 4) spaced-plant seed-increase nurseries were established and evaluated for growth and reproductive traits. We will report observations from the actual selection experiment as well as from the seed-increase nurseries.