Submitted to: Agronomy Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 11/6/2003
Publication Date: 11/6/2003
Citation: KOVAR, J.L., DOERGE, T.A. EARLY GROWTH AND NUTRIENT UPTAKE OF TRANSGENIC AND NON-TRANSGENIC CORN HYBRIDS. ASA-CSSA-SSSA ANNUAL MEETING ABSTRACTS. 2003. CD-ROM. MADISON, WI.
Technical Abstract: Information on the nutrient requirements and growth habits of newer transgenic corn hybrids is needed. To evaluate hybrid responses to fertilizer placement, a pot experiment was conducted in a controlled-climate chamber. Fertilizer was added to Clarion silt loam (fine-loamy, mixed, mesic Typic Haplaquolls) at two rates comparable to those used in a previous field trial (22-30-19 or 67-30-19 kg nitrogen-phosphorus-potassium ha-1, respectively). Three kg of soil (dry-weight basis) were placed in 3.8-L plastic pots, vertically divided into five parts with plastic screens. Fertilized soil was placed in a 0.20 fractional volume. Seedlings of two isolines (non-transgenic hybrids Pioneer 36R10 and 33P66 and transgenic hybrids Pioneer 36R11YG and 33P67YG) were planted two per pot and grown 13d. At harvest, roots growing in fertilized soil and a comparable unfertilized 0.20 fraction were removed separately. Preliminary results suggest that the non-transgenic corn hybrids were better able to take advantage of the available nutrients in the Clarion soil than were the transgenic hybrids. Dry matter accumulation was greater for both non-transgenic hybrids, regardless of fertilizer rate or placement. Based on measurements of root length in fertilized and unfertilized soil, the non-transgenic hybrids also were better able to respond to fertilizer placement. It is difficult to draw conclusions because information on plant uptake of nutrients is not yet available.