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United States Department of Agriculture

Agricultural Research Service

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Location: Corn Insects and Crop Genetics Research

2012 Annual Report

1a. Objectives (from AD-416):
Phenotypic data will be collected on the parents and progeny of the Nested Association Mapping (NAM) populations. Field tests will total 28,800 plots annually and data will be collected on seed protein and oil content, yield, plant maturity, height and lodging. Locations of genes controlling these characters will be determined within the objectives of a separate USB-funded project.

1b. Approach (from AD-416):
The research will be conducted using a series of 40 mapping populations that each contain 140 experimental lines giving a total of 5,600 experimental lines across all populations. These populations were developed by mating the maturity group (MG) III variety IA3023 with 40 diverse parents (i.e., soybean varieties and experimental lines). The 5,600 lines in the Nested Association Mapping (NAM) populations will be grown in field tests during 2012 to 2013. One replication of the full set of lines will be grown in Ames, IA; Lincoln, NE; and Urbana, IL. In addition to growing these full sets of lines, partial sets of the populations will be grown in Carbondale, IL; Manhattan, KS; southern MI, Columbus, OH; Wooster, OH; and Portageville, MO. The NAM populations will be field evaluated in 2-row yield plots using standard procedures and managed to achieve optimal yields. Traits measured on each plot include: seed yield, maturity (number of days from planting to R8), plant height (cm from ground surface to stem tip), lodging (rated from 1.0 = erect to 5.0 = prostrate), 100-seed weight (gram weight of a representative sample of 100 seeds at 13 percent seed moisture), and seed protein/oil (gram weight of protein and oil per kg of seed at 13 percent seed moisture). Seed protein and oil content will be determined by near infrared spectroscopy of a seed sample from each individual plot. The analysis is non-destructive, so additional compositional tests can be conducted using the same seed sample if there is future interest. Breeding values for yield and other traits will be calculated for each of the 5,600 lines. As part of another project, the NAM populations will be mapped with 1536 SNPs and the traits will be mapped as Quantitative trait loci (QTL). This information as well as the NAM populations will be made publicly available.

3. Progress Report:
During the reporting period, a focus of the Nested Association Mapping (NAM) project has been to organize experiments and prepare seed for the 2012 field tests. The 5,600 experimental lines in the study were divided into sets and decisions were made on what sets would be grown in each location of the experiment. Progress was made in conducting the field experiments that are part of the NAM project. Seed for the 37,600 plots are being grown in 2012 across all locations of the experiment. This included seed for 2,000 plots that was sent to Southern Illinois University, The Ohio State University, and USDA-ARS collaborators in Ohio, 6,400 plots planted at the University of Illinois, Iowa State University, the University of Nebraska, and Purdue University, and 1,000 plots planted by at Michigan State University and at the University of Missouri. The locations were planted on the following dates: May 10 – University of Nebraska, University of Illinois, and University of Missouri, May 11 – USDA-ARS at The Ohio State University, May 12 –The Ohio State University, May 15 – Kansas State University, May 16-17 – Purdue University, May 20 - Iowa State University, June 2 – Southern Illinois University, and June 5 – Michigan State University. The plots are now being maintained weed free.

4. Accomplishments

Last Modified: 10/17/2017
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