Agronomic evaluation of white clover selected for increased floral condensed tannin

Abstract

The agronomic performance of an experimental white clover (HT) selection bred for increased floral condensed tannin (CT) production and extended flowering season was compared with Grasslands Huia white clover, under dairy cow grazing in the Waikato. Pure clover swards were sown at 5 kg/ha in autumn 2001. Seedling establishment was better in HT than Huia, but stolon growing point densities from January 2002 to May 2003 were 13 to 62% greater in Huia than HT. Huia swards had higher clover contents than HT, and produced 0.8 t/ha more DM (dry matter) in the first year. CT concentr ations in the flower heads varied over the season, but were similar in the two clovers (1 to 8% of DM). Higher flower densities in HT resulted in higher clover CT concentrations (peak of 0.6 vs 1.2 % of DM for Huia and HT, r espectively). Further testing is required to determine any effects of HT on animal performance. Keywords: condensed tannins, flowering, growing point density, Trifolium repens, white clover