Factors underpinning improved productivity in the WA wheat industry

Wheat yields in the Western Australian wheat industry have risen by about 3.9 percent per year over a period of 20 years. This has coincided with a decline in growing season rainfall over the grain belt. However, in the last few years yields have been highly variable because of fluctuations in rainfall and because two of the three driest years in the last 70 years have occurred during the last five years. Farm managers, consultants, researchers and research funders need to understand the key drivers of improvements in productivity. Researchers from the Department of Agriculture, Western Australia have conducted intensive research on wheat varieties and management practices needed to achieve high wheat yields. These have been combined into recommendations known as High Yield Packages (HYPs) for the regions of the state. The question addressed in this paper is which elements of these packages have been important and what other factors may have contributed to the improvements in productivity.Using graphical, statistical and regression analysis of benchmark data from PlanFarm Consulting group for 1995 to 2004, supported by in-depth qualitative analysis of 40 case study farmers, and a random telephone survey of 100 farmers, key factors associated with yield increases were investigated. The evidence suggests farmers have increased their water use efficiency since 1995 and that improvements in productivity are associated with nitrogen and phosphorous use, herbicide use, higher seeding rates and management performance. There is also qualitative evidence to suggest that the widespread adoption of one pass operations or no-tillage systems has been an important complementary factor