|Brummer, Charles -|
Submitted to: Crop Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: April 18, 2014
Publication Date: May 7, 2014
Citation: Riday, H., Brummer, C.E. 2014. Vigor and persistence of birdsfoot trefoil (Lotus corniculatus L.) populations selected with or without an orchardgrass (Dactylis glomerata L.) companion evaluated in grass sod. Crop Science. DOI:10.2135/cropsci2014.02.0147. Interpretive Summary: Forage legumes such as birdsfoot trefoil are grown in pastures in mixtures with grasses. In order to breed better birdsfoot trefoil varieties adapted to these pasture situations, breeders should select birdsfoot trefoil plants in competition with grass. This study shows the advantage of selecting (breeding) birdsfoot trefoil plants grown in competition with grass versus selecting (breeding) birdsfoot trefoil plants not in competition with grass. The varieties developed in competition with grass were longer lived (had better persistence) and generally had more forage production compared to the varieties developed without grass competition. This information will assist plant breeders in selecting and developing legume varieties that are best suited for growing with grasses, which will ultimately help grazing-based livestock producers and/or forage producers to be more efficient.
Technical Abstract: Forage legumes are often grown in mixtures with grass for grazing or harvested for hay or silage. Forage legume breeders often debate the necessity of incorporating grass competition into the breeding process, particularly when bred varieties will be utilized in mixture with grass. To address the value of selecting with a companion grass, a two by two by two factorial of eight birdsfoot trefoil (Lotus corniculatus L.) populations were developed from selections of plants made at two nursery sites (Boone, IA and Prairie du Sac, WI), out of two base cultivars (‘Norcen’ and ‘WITT’), and under two nursery treatments (orchardgrass [Dactylis glomerata L.] overseeded and no-grass overseeded). Space-plants of the eight birdsfoot trefoil populations were transplanted directly into grass sod and evaluated for four years for visual vigor (a proxy for biomass yield) and plant persistence. Persistence over time was measured using a linear model describing the decline in stand percentage per month. Overall, the four birdsfoot trefoil populations bred with a grass companion persisted better when transplanted into grass sod (slope -1.12% persistence month-1) compared to the four birdsfoot trefoil population bred without a grass companion (slope -1.43% persistence month-1). On average, only the WITT derived populations selected with a grass companion had superior visual vigor ratings when transplanted into sod compared to the WITT derived populations selected without a grass companion. This study provides evidence that selecting birdsfoot trefoil with an orchardgrass companion leads to more persistent birdsfoot trefoil varieties for use in grass mixtures compared to birdsfoot trefoil bred without a grass companion.