Australian rice is grown in summer. Production has evolved over recent decades to improve water-use efficiency by reducing the amount of water required to grow a crop through shorter season varieties and delayed application of permanent water. The absence of water during the early stages of rice growth and the delay in application of permanent water provide an attractive environment for the proliferation of barnyard grass (Echinochloa crus-galli), a highly competitive weed of rice. Barnyard grass is considered a major constraint to the productivity of rice in the water-saving systems of southeastern Australia. The introduction of pasture legumes into rice rotations may provide an opportunity for increased productivity, to mitigate environmental concerns and to improve weed management. Rice growers have limited experience with annual winter pasture legumes in rotation with a summer-grown rice. However, these pasture legumes may provide opportunities to manage barnyard grass to deplete seed banks and reduce weed growth. The biological and ecological features of barnyard grass that favour its proliferation and control under these systems are discussed. Opportunities for pasture legumes to suppress weeds in rice include growth inhibition (allelopathy and competition) and reduced weed seed longevity and viability. Recommendations are provided for future research and development required to realise the potential benefits of pasture legumes for weed management in the temperate rice production systems in Australia.
|Number of pages||13|
|Publication status||Published - 2021|