Trends in Cropping Systems and Yield Gaps in the Central High Plains.

Competition among the food, feed, and biofuel industries has intensified agricultural production systems, but much of the yield enhancement gained through improvements in genetics, production technologies, and management protocols is being eroded and lost through yield stagnation, yield decline and increases in year-to-year variability. This yield gap — the difference between the yield potential of a cultivar as measured from controlled research fields and the actual yield harvested by farmers — represents an inefficient conversion of inputs to harvested crop and hence loss of return on investment. Many factors may play a role in exacerbating the yield gap, including growing environment (temperature, sunlight, and rainfall), poor soil quality, fertilizer inefficiency, and narrowed genetic diversity. The inability to capture the genetic yield potential of crops hinders agronomic production capacity and economic return and threatens the long-term sustainability of agricultural production. We examined historical production records and yields to delineate changes in cropping systems. On-farm measurements of crop performance and soil quality are used together with climatic conditions to delineate factors contributed to the yield gap. Although corn and soybean acreage has increased recently, these crops are more sensitive to high temperatures and rainfed production than sorghum. The research will be used to develop improved production methods to enhance the yield harvested by farmers in a consistent way.