Comparison of Brazilian and naturalised Australian ecotypes of Stylosanthes humilis in the dry tropics of Queensland

Abstract

Nine Stylosanthes humilis introductions from Brazil were compared with four Australian ecotypes and two mixtures when grown in swards with a grass Urochloa mosambicensis at two sites in the dry tropics of Queensland with an average growing season of 22 weeks per annum. The swards were harvested at 6-weekly intervals during the growing season at a height of 7.6 cm. Over the three years of the trial, no introduction was superior to cv. Gordon in dry matter and pod yield at the two sites. The Brazilian introductions showed variation in flowering times and growth habit. In general the later flowering, erect types were more productive because they made better growth late in the season, still set seed and competed better with sown grass. The naturalised Australian material gave higher pod yields but lower in vitro digestibilities during the dry season than the Brazilian introductions.