Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: January 5, 2001
Publication Date: February 5, 2001
Cadmium is present in all plants; crops differ in their tendency to accumulate Cd, with sunflower, flax and durum wheat accumulating higher Cd levels in grain than most other crops. Because kernel Cd concentration would limit export sales of nonoilseed sunflower kernels, we undertook a research program to develop agronomic methods to reduce kernel Cd to retain the markets. The effect of soil series and soil properties were tested by sampling a major hybrid grown in many farmers' fields along with soil. This study showed that poorly drained heavy textured soils in the Red River Valley caused considerably higher Cd uptake at similar total soil Cd, and identified soil series where kernels with low Cd could be reliably produced. This test showed that the soils of this region were not contaminated with Cd; that DTPA- extractable Cd was a strong predictor of kernel Cd; and that soil chloride could increase kernel Cd. Thus certain areas with pedogenic chloride would not produce marketable kernels. Another approach was identification of genetic sources of lower Cd so that low Cd hybrids could be generated so that all growers could market sunflower kernels. Low Cd germplasm was identified by field tests, and the combining ability of inbreds in hybrids showed that low Cd types could be attained. Lastly, testing of bioavailability of kernel Cd compared to rice has identified reasons that Cd in sunflower kernels can cause little risk to consumers because the kernels are a good source of Zn and Fe.