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ARS Home » Midwest Area » Ames, Iowa » Corn Insects and Crop Genetics Research » Research » Research Project #421241


Location: Corn Insects and Crop Genetics Research

2013 Annual Report

1a. Objectives (from AD-416):
1) Contribute populations to and provide testing sites/evaluations for a joint experiment to catalog germplasm for organic production, 2) cooperate in a breeding effort concentrating on the northeast, 3) take the lead in breeding/evaluation for host plant resistance to foliar pathogens gray leaf spot, northern leaf blight, anthracnose leaf blight and stalk rot, 4) participate in USTN trials and pre-trials, and 5) cooperate in on-farm evaluations and stress nurseries.

1b. Approach (from AD-416):
Conduct joint trials using locations in the northeast, and using the improved breeding populations that each breeder has developed. In year one each breeder will submit approximately 10 populations, thereafter the best performing populations will be retested while additional populations from the breeders’ programs or acquired elsewhere are evaluated. Identify and test superior parents on a somewhat continuous basis, so there is a constant flow of our best hybrids to farmers and seed companies for testing and increase. Make numerous crosses between parents with desired traits, hybridizing those crosses with multiple testers, examining the hybrid test crosses in yield trials and thereby identifying the best crosses to work with, then selfing the best of those families to the S3 stage while systematically testing resulting lines in test crosses. The best S3 lines will be further tested, selected, and developed as inbreds for making hybrids or recombined to make synthetics which will receive additional testing to identify those that best fit the organic ideotype. Because speed is essential we plan to do early and repeated testing for combining ability in top cross hybrids allowing resources to be devoted to those populations that demonstrate the greatest potential early on. Winter nurseries will be used to make new crosses, to self F2 plants, to make necessary topcrosses, and to self the summer’s topcrosses to test their grain quality. Experimental hybrids from the breeding programs will be tested in small replicated plot trials at cooperating organic farms managed by the breeder. In addition, selected varieties from the plot trials will be tested in large strip-trial plots on farms. Breeding lines will be evaluated for stress and pest resistance in breeding nurseries and specialized testing will be done at a stress nursery in Illinois.

3. Progress Report:
Cornell University scientists completed a summer breeding nursery including organic and pest resistant selections; harvested and presented data from organic hybrid and population trials and United States Testing Network (USTN) trials; carried out an organic winter breeding nursery; and established a second year of summer breeding nursery and yield trial plots. These activities are described below in more detail, focusing first on breeding nursery and then on yield trial activities. The Cornell University 2012 summer breeding nursery at Aurora, New York included over 450 rows of progenies for observation and selection in a certified organic nursery, over 450 progenies for disease resistance observation and selection, and over 180 progenies for insect resistance observation and selection. A project aiming to breed hybrids that could minimize the chances of contamination by genetically engineered corns was pursued in about 150 breeding nursery rows. Among these nursery rows, those families and plants that showed the best performance were pollinated and subjected to further selection at harvest. These and other germplasm sources were advanced another generation in a 400-row organic winter breeding nursery in Lajas, Puerto Rico. Despite weather-related planting date challenges in Puerto Rico, we had a good winter nursery and were able to get seed back from most rows. Our summer 2013 breeding nursery was planted in early June and includes about 375 rows being selected under organic management, over 550 rows being selected for disease resistance traits, and over 200 rows being selected for insect resistance. Additionally, we have about 220 breeding rows dedicated to development of hybrids that will minimize the potential for pollination by genetically-engineered corn pollen and provide markers for any accidental contaminations in plants and seed. Selection and pollination will be made in all of this material in summer 2013. Yield trial activities during this project period included harvest and data analysis of 2012 trials and establishment of 2013 yield trials. In October and November of 2012, we harvested yield trials from organic sites that included: an evaluation of 21 experimental hybrids/varieties from our breeding program compared with four checks in three replications at both locations; a two-replication evaluation of 34 breeding populations (some from each of the collaborating breeding programs working on this project) compared with three checks at one location; and a USTN organic trial of 16 experimental hybrids evaluated in two replications at one location. Data were summarized and shared as appropriate. Among our Cornell-developed experimental hybrids and varieties, seven of them performed well enough to merit a second year of testing in 2013. These seven were combined with four new experimental hybrids and five experimental open-pollinated varieties from Cornell, four hybrid checks, and three open-pollinated variety checks and planted in three replications in each of two organic locations this year. Another breeding population trial (37 populations in two replications, including second year evaluation of nine Cornell populations) was planted at one organic location. A USTN organic trial (29 varieties in two replications) was planted at two organic locations. All trials have been thinned to a uniform plant density and will be rated for any diseases and insects that show uniform damage, scored for stalk and root lodging, and harvested to assess grain yield and moisture. From this breeding program, organic seed of one hybrid is being produced and marketed commercially. The work being done as part of our organic corn breeding effort was described at a Cornell Organic Program Work Team meeting in January 2013, the Minnesota Organic Conference in St. Cloud, Minnesota in January 2013, the Northeast Organic Farming Association of New York conference in March 2013, and a field day visit of graduate students from the Great Lakes area of the U.S. and Canada in June 2013.

4. Accomplishments