Determining aluminum tolerance and critical soil pH for winter canola in the Southern Great Plains.

摘要

Scope and method of study. An in-field study was conducted to determine the effect of soil acidity on winter canola grain yields. A pre-established soil pH gradient was used in Perkins, Ok. A randomized incomplete block design with 6 cultivars per block was established. A laboratory experiment was established to determine the effect of aluminum concentrations on root growth and determine if the different cultivars responded differently to the changing aluminum concentrations. Eight cultivars were chosen. The treatments consisted of 0, 20, 40, 60, and 80 mg Al kg-1. The seeds were allowed to germinate and grow for 72-hours in DI water. The seedlings were then transplanted into the varying concentrations of aluminum and allowed to grow for 96-hours. Root lengths were then taken and compared between the aluminum concentrations and between cultivars.;Findings and conclusions. Soil acidity greater affected winter canola grain yields for both 2006-2007 and 2007-2008 growing seasons. In the 2006-2007 growing season the current critical level for growing winter canola, pH 5.8, was found to be adequate; however, in 2007-2008 not enough data points were found above 5.8 to see the same results. In the laboratory study it was found that for most cultivars Al concentrations as low as 20 mg Al kg-1 were found to reduce canola root growth. Overall, the effects of soil acidity highly effects winter canola production in the Southern Great Plains. For non-weather stressed years a critical pH of at least 5.8 will be appropriate for winter canola production.