Rain, rain, gone away. Decreased growing season rainfall for the dryland cropping region of south-western Australia

The shift in Indian Ocean sea surface temperatures in 1976 led to a change in rainfall for the broad-scale winter annual grain cropping and pasture region in the south-west of Western Australia (the WA wheatbelt). Agriculture in the eastern part the WA Wheatbelt was particularly sensitive to the change in rainfall because it is a marginal area for agronomic production, with low rainfall before changes in sea surface temperature. A second shift in sea surface temperature occurred in 2000, but there has been no analysis of the resulting impact on rainfall in the eastern WA wheatbelt. An analysis of rainfall pre- and post-2000 was performed for sites in the eastern WA wheatbelt in three groups: 19 sites in the west, 56 central, and 10 east. The analysis found a decline in growing-season rainfall (i.e. April–October), especially during May–July, post- 2000. Rainfall declines of 49.9mm(west group), 39.1mm(central group) and 28.0mm(east group) represented respective losses of 20.1%, 17.4% and 14.2% of growing-season rainfall. Increases in out-of-season rainfall in the respective groups of 31.0, 33.6, and 50.7 mm (57.8%, 60.8% and 87.6%) meant that annual rainfall changes were smaller than growing-season losses. The west and central groups lost 17.5 and 6.16 mm annual rainfall, whereas the east group gained 15.6 mm. Analysis of wheat yield indicated reductions of 13.5% (west) and 9.90% (central) in the eastern WA wheatbelt; the small group of east sites had a potential yield gain of 8.9% arising from the increased out-of-season rainfall. Further, increased out of- season rainfall will exacerbate weed and disease growth over the summer fallow

Crop Updates 2010 - Weeds

This session covers eighteen papers from different authors: Herbicides 1. Herbicide control of slender iceplant, Lorinda Hunt, and Andrew Blake Department of Agriculture and Food 2. Herbicide tolerance of saltbush and bluebush, Lorinda Hunt, and Andrew Blake Department of Agriculture and Food 3. Chemical control of windmill grass, Catherine Borger, Glen Riethmuller and Abul Hashem, Department of Agriculture and Food 4. Use high water rates when applying pre-seeding herbicides to fields with high stubble density, Catherine Borger and Abul Hashem, Department of Agriculture and Food 5. Herbicide tolerance of lupins – influence of soil type and rainfall, Harmohinder Dhammu and David Nicholson, Department of Agriculture and Food 6. Response of new barley varieties to herbicides, Harmohinder Dhammu, Vince Lambert and Russell Quartermaine, Department of Agriculture and Food 7. Herbicide tolerance of new wheat varieties, Harmohinder Dhammu and David Nicholson, Department of Agriculture and Food Herbicide Resistance 8. Use of below label rate can lead to evolution of herbicide resistant weeds, Roberto Busi , Todd Gaines, Sudheesh Manalil and Stephen Powles, Western Australian Herbicide Resistance Initiative, School of Plant Biology, Faculty of Natural and Agricultural Sciences, The University of Western Australia 9. Herbicide mixtures can effectively kill herbicide-resistant weeds, Aik Cheam and Siew Lee, Department of Agriculture and Food 10. Selective spray-topping: Does it abort seed production of herbicide-resistant radish? Aik Cheam and Siew Lee, Department of Agriculture and Food 11. The search for a new lupin herbicide, Peter Newman, Department of Agriculture and Food Integrated Weed Management 12. Colonisation of agricultural regions in Western Australia by flaxleaf fleabane, Catherine Borger, Greg Doncon and Abul Hashem, Department of Agriculture and Food 13. Weed suppression by crop competition in barley, canola and wheat, Abul Hashem and Catherine Borger, Department of Agriculture and Food 14. Mouldboard plough continues to kick goals, Peter Newman and Dr Steve Davies, Department of Agriculture and Food 15. The answer my friend is to burn in light wind, Peter Newman, Department of Agriculture and Food, and Michael Walsh, Weeds Researcher, University of Melbourne 16. Using image analysis to detect three-horned bedstraw seed in grain samples, John Moore, Department of Agriculture and Food, Murray Gillespie, Lygil Holdings, Albany 17. Can we manage brome and barley grass in cereals? Sally Peltzer, Abul Hashem and Alex Douglas, Department of Agriculture and Food 18. Control of mature fleabane, Sally Peltzer, Department of Agriculture and Foo