New perennial plant options needed to transform agriculture and manage salinity

摘要

While current levels of salinity are a major driver for change in agricultural land use, it is the predicted expansion in the area affected by salinity that is motivating an ongoing search for additional solutions, Slowing or reversing the rise of water tables is at the heart of salinity prevention. Wide-scale adoption of land uses based on perennial plants has been identified as a primary strategy to increase water use and reduce the volume of water entering ground water systems, Where salinity is already expressed there is a need to grow salt tolerant plants, particularly where they contribute to profitable and stable land use. Given the past focus on exotic annual plants, many potentially useful native and exotic perennial species have received limited study and have not been the subject of systematic plant improvement programs. Plants with specialised traits such as salt and waterlogging tolerance are also likely to be increasingly in demand in the future. A cautious policy imposing quarantinebarriers to the introduction of further exotic plants (precautionary principle) is in place to prevent the introduction and proliferation of potentially weedy species. This approach works well where adequate data exist to allow accurate predictions, Further developments are needed to allow better evaluation of potential introductions with little baseline data. Weed risk assessment strategies are also required for exotic species already introduced to Australia and therefore not covered by barrier assessments, and for native species. Weed risk minimisation approaches can be usefully applied to all stages of plant breeding and better and more widely accepted operating procedures need to be developed through the collaborative efforts of plant breeders andweed scientists.