Dryland legumes: perspectives and problems

Abstract

The different perspectives or concepts involved in developing legumes for dryland pastoral systems is commented on in relation to: N-fixation versus animal feed; root nodule bacteria requirements; large introduced legume flora compared with indigenous; species niche in relation to environmental gradients of moisture, temperature, fertility, and grazing; species adaptation along the decreasing fertility gradient from fine-root nutrient scavenging grasses, N-fixers, mycorrhiza, and proteoid roots; interaction of N- fixation with soil organic matter; establishment; determinants of pastures legume composition; and the possible role of allelopathy. Key words: dryland, environmental gradients, legumes, N-fixation, pasture composition