Submitted to: American Forage and Grassland Conference Proceedings
Publication Type: Proceedings
Publication Acceptance Date: May 15, 2007
Publication Date: June 24, 2007
Citation: Cassida, K.A., Turner, K.E., Foster, J.G. 2007. Polyphenol oxidase activity in annual forage clovers. In: Alison, W., editor. Proceedings of the American Forage and Grassland Council, June 24-26, 2007, State College, PA. 16:82-84. Technical Abstract: Polyphenol oxidase (PPO)-mediated phenol reactions in red clover (Trifolium pratense L.) bind forage protein and reduce proteolysis, producing beneficial effects on forage protein degradability, silage fermentation, and soil-N cycling. We evaluated PPO activity in seven previously untested annual clover species (arrowleaf [T. vesiculosum Savi], bigflower/balansa [T. michelianum Savi ], berseem [T. alexandrinum L.], crimson [T. incarnatum L.], persian [T. resupinatum L.], rose, [T. hirtum L.] subterranean [T. subterraneum L.]) using red clover as a positive control. Plants were grown in individual containers using a 12-hr photoperiod in a growth chamber. Substantial PPO activity was detected in red, subterranean, rose, and berseem clovers, but not in persian, balansa, crimson, or arrowleaf clovers. Among the species positive for PPO activity, berseem clover exhibited the greatest degree of activity, followed by rose clover, with red clover and subterranean clover the least. Berseem clover cultivars differed in degree of PPO activity. Berseem, rose, and subterranean clovers may exhibit similar proteolytic characteristics as red clover, and may be better adapted to some environments where red clover does not thrive. More research is needed to relate growing condition effects on PPO activity in legumes and grasses, and the benefits of PPO-active plants on grazing livestock performance and meat quality.