Germplasm Enhancement of Maize
- 1995 Annual Report
1994 Technical Advisory Committee (TAC) Meeting, Chicago, IL
The TAC recognized the important contributions of Bill Kuhn, Jim Parks and Dave Harper in lobbying and encouraged cooperators to write thank you letters to key people in Congress. Charles Murphy, USDA-ARS National Program Staff member for grain crops, discussed allocation of the $500,000 appropriated by Congress. After 10% ($50,000) overhead, $300,000 would be added to Linda Pollak's CRIS to support GEM coordination, data management and analysis, evaluation of value-added traits, management and release of enhanced germplasm, and participation as a breeding site.$150,000 would be added to Marty Carson's CRIS (Raleigh, NC) for support of coordinating development of enhanced materials for the South, and to serve as a stepping stone for adapting tropical material to the Midwest. Three USDA-ARS support scientists would be hired to work on GEM, one for germplasm enhancement and breeding in NC, one for value-added trait analyses in IA, and one for data management and analysis in IA. Other matters discussed were an early screening of LAMP populations using smaller sample size, choice of tester for evaluating breeding crosses, value-added trait evaluations with ISU cooperators, and membership (diversity, rollover) on the TAC.
1994 Cooperator's Meeting, Chicago, IL
Reports were given by:
Many of the items discussed at the TAC meeting were presented for cooperator's comments. Major points made by cooperators included:
Dirk Benson was added as an industry member of the TAC with expertise in breeding and entomology. Marty Carson was added as a USDA-ARS ex-oficio member of the TAC representing the North Carolina GEM satellite location and with field pathologist expertise, unless he delegates membership to the support scientist to be hired.
Development of Breeding Crosses with Private Inbreds
The initial accessions and tropical hybrids of GEM (400k/accession, 200k/tropical hybrid) were sent to private cooperators for crossing to private inbred lines in the 1994-95 winter nursery. Each private cooperator was assigned to make at least four crosses. No direction was given to cooperators on specific attributes of the inbred line other than the heterotic pattern to use (Stiff Stalk of non-Stiff Stalk) and that it should be a commercial line.
Support Scientist for Evaluating Value-Added Traits
In February, Susan Duvick was hired as a USDA transfer to fill this position. She had experience evaluating starch and oil quality while a research associate for the Center for Crops Utilization Research at Iowa State University, and experience evaluating protein quality while a technician for the USDA-ARS.
1995 Technical Steering Group (TSG) Meeting, Champaign, IL
Composition and Membership of TSG:
The name of TAC was changed to Technical Steering Group, because Congress decided that only they could set up Advisory Committees for government work. Blaine Johnson resigned as a University member of the TSG. TSG membership was determined to be 9-11 members. Composition can float, but an industry minimum of five was set. Ideally, these members would be diverse among large, regional, medium national, and foundation seed companies. USDA-ARS members are limited to two (GEM coordinator and North Carolina representative), and are ex-oficio due to conflict of interest. One commodity group or processor member and two university members should be added. Rollover dates were assigned to all members, with terms running from January 1 through December 31.
1995 TSG Committee Membership
Priorities for screening pests/diseases (1=high, 2=medium, 3=low priority)
Other items discussed included: protocol for selecting public cooperator's projects for funding by specific cooperative agreements, update on Dave Harper's lobbying of both houses of Congress's Ag. Appropriations Committees on February 9-10, status of breeding crosses, and need for cold storage at both GEM locations.
Public GEM Cooperators Supported by Specific Cooperative Agreements
or USDA-ARS transfers in 1995
Development of 3-way Breeding Crosses with Private Inbreds
Private cooperators returned exotic x private inbred breeding crosses to Linda Pollak from winter nurseries in the form of balanced bulks for future breeding and for making 3-way crosses, and leftover bulks for other evaluations (Table 1).Balanced samples (200k) of the breeding crosses were sent to two different companies for making 3-way SS or nSS breeding crosses in summer nurseries or day-neutral locations. Each private cooperator was assigned at least eight crosses. New private cooperators were assigned four accessions (400k each) to make breeding crosses. Balanced breeding bulks were kept in cold storage for further use. Due to limited cold storage space, leftover bulks were stored at the Plant Introduction seed storage in Ames.
1995 TSG Meeting, St. Louis, MO
North Carolina's method for following the 50% breeding cross protocol: Self F1 50-200 ears, bulk equal numbers, self and get 1000 plants, grow ear-to-row etc. These modifications are necessary because of environmental conditions unique to the South (e.g.. soil variability).
GEM Fast-Track Program
Randy Holley devised a protocol to develop a quick product using small sample sizes, then best crosses can be re-sampled. This protocol will be followed by the USDA-ARS locations in North Carolina and Iowa and a few companies for the 75% breeding crosses. Development of early good lines will benefit GEM's publicity and lobbying efforts.
Winter 1 Plant 100k per breeding cross. Harvest 50 S1's and shell individual ears.
Summer 1 Plant 50 S1 rows per cross with intermittent reference inbred between each cross. Try to follow the planting and pollination practices of local breeders. This may include high density planting with disease inoculations and at least three self pollinations per row. Take notes on strengths and weaknesses of entries by population to aid in selection of populations for further advancement. Harvest at least one ear from each row that meets standard agronomic selection criteria. This will probably average 5 ears/cross.
Winter 2 The number of breeding crosses under consideration should be cut by at least 70% via preliminary review of topcross yield trials (evaluated in 1996 according to the original protocol), cross per se observation in nurseries, and S1 derivative performance in nurseries. Less than 10 S2s from each selected population should be crosses onto two or three testers providing ~500k of each entry for yield trials the following summer.
Summer 2 Yield trials of selected S2 topcrosses will be run at six locations, one replication. From this point on entries will follow standard GEM protocol. Yield data collected will be used to prioritize yield trials of various breeding materials in the pipeline and better identify testers for larger numbers of S2s from the selected populations.
Other major items discussed:
1995 Field Days
Ames, IA. The field day was held on September 14 (3-5 pm) in association with Iowa State University's Agronomy Day (9-3pm).Many of the 3000 attendees of Agronomy Day visited the GEM field and tent during the day on guided tours, increasing exposure of GEM to farmers and the general public. A brochure was developed to give general information about GEM. Available for viewing in the field were all private line breeding crosses, comparisons of private and public line breeding crosses, and a demonstration of breeding progress in Corn Belt and exotic corn. Other displays and talks included:
Madison, WI hosted by Jim Coors. The field day was held on September 19, 1995 and focused on temperate germplasm and associated private line breeding crosses that were under evaluation for silage nutritive value. It also included a demonstration of silage germplasm and summaries of silage studies conducted over the past four years by researchers at the University of Wisconsin. Susan Duvick displayed poster demonstrations and discussed laboratory value-added evaluations. Both field days were very successful.
1995 TSG Meeting, Ames, IA
Main topics discussed included:
1995-96 Winter Nursery Plans
Two companies (Golden Harvest and Pioneer) are making nSS testcrosses with all available SS breeding crosses, and two companies (Cargill and Holdens) are making SS testcrosses with nSS breeding crosses. Three companies and the USDA-ARS locations in Ames and Raleigh are doing fast-track breeding. Thirteen companies are remaking 2-way or 3-way breeding crosses that failed. Two companies have no winter nurseries.
Status of GEM Breeding Crosses
The following table gives numbers of GEM breeding crosses as of December 1995.All crosses were sent to appropriate companies for making testcrosses. Most of these crosses have adequate seed supplies for pest and quality evaluations and for distribution to cooperators. Some have only enough seed supply for making testcrosses and for the GEM protocol breeding procedure.
GEM Breeding Cross Totals
Support Scientist for Data Management and Analysis
Eric Wellin will start at this position on December 11, 1995.He had experience in computer maintenance, networking, Foxpro programming, data management and analysis, and corn breeding as an assistant breeder at Cargill Hybrid Seeds.
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