R.M. JONES and M.C. REES

CSIRO Tropical Agriculture, Brisbane, Australia

Abstract

A range of legume accessions were evaluated for persistence and productivity in small plots on 4 clay soil sites in southern inland Queensland from 1987–1995. The legumes were sown with and without a companion grass, usually purple pigeon grass (Setaria incrassata) cv. Inverell. Clay soils in this region are used for both cropping and grazing; thus, annual, short-term perennial and long-term perennial species were included in the experiments. Good growth was achieved at 2 sites, fair growth on 1 and poor growth on another. The differences between sites were partly due to rainfall, and partly to differences in competition from weeds, seedling emergence, residual effect of herbicides, and soil type.
The presence of a dense, vigorous companion grass in the year of sowing markedly depressed legume yield in this and the following year, but had less effect thereafter. Promising annual and short-lived perennial accessions included lines of Vigna, Macrotyloma and Macroptilium spp. as well as Lablab purpureus, which is currently used. The promising perennial legumes were: Desmanthus virgatus CPI 78382, Indigofera schimperi CPI 52621 and 69495, and at one site, Glycine latifolia cv. Capella.