Developing perennial shrubs to fill feed gaps on marginal soils in Australia

摘要

This paper presents data and discusses work being conducted in Australia to improve the feeding value of drought-tolerant shrubs through simple plant selection. The programme targets saline, sandy and infertile soils in low rainfall zones that are marginal for cropping. The shrubs are used to complement the abundant and poor-quality crop and annual pasture residues during the summer and autumn seasons. Plant improvement criteria were determined through whole-farm economic modelling, with increasing energy and protein content the key target. Biomass and nutritional value data of 19 accessions from 7 species growing in a moderately saline environment are presented. The data show there is significant opportunity for selection of improved cultivars. This approach has already been used to commercialise Anameka~(TM) saltbush (Atriplex nummularia), a cultivar with higher energy concentrations, greater biomass production and improved 'palatability'. Work is continuing with the development of elite A. nummularia seed lines (to halve the cost of establishment) and to identify improved accessions of Rhagodia preissii for sandy and infertile soils in dry areas. Adoption of these shrubs will lead to improved profitability and environmental health.