CORN

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ANNUAL REPORT
Richard Pratt Dept. of Horticulture and Crop
Science The Ohio State University Ohio
Agricultural Research and Development
Center Wooster, OH
GEM Cooperator Annual Meetings Dec. 2002 Chicago,
IL
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Release of GEMS-002Maize Germplasm Line

• Breeding
• Test Cross Data Summary
• Inbred Characterization
• Recommendations

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Breeding followed GEM protocol

• Breeding line OSU 43-2 derived from GEM
  population FS8(A)SS09 (FS8(A) 50 BSSS related,
  21 tropical, 18 southeastern U.S., and 11
  diverse Corn Belt (with a high proportion of
  inbred C103A
• Produced S1s (441)
• Visual Selection, self 2 per line in IA and OH
• Select lines in IA and OH gt S2 winter nursery
  testcross to nSS tester LH185
• In 1999 11 one-replicate tests at 10 locations
  in IA, IL, IN, and OH
• In 2001 9 one-replicate tests at 7 locations in
  IA, IL, and OH (Mo17 and Oh43 related testers)

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Testcross Data Summary

• Demonstrated good combining ability with three
  non-BSSS testers
• Average yield of the testcrosses across 17
  locations during two seasons was approx. 95 of
  the mean of commercial check hybrids
• Yields equivalent or higher than checks at sites
  that experienced drought stress, and below in the
  high-yield tests of 2001
• Moisture content consistently below the average
  of the check entries (avg. 1.5) and stalk
  lodging was approximately equal (avg. 7)

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GEMS-002 Inbred Characterization
Plant Height Avg. 133 cm ltlt B73
Ear Height Avg. 56 cm ltlt B73
Ear Length Avg. 13.2 cm (11 to 15)
Ear Width Avg. 3.8 cm ( 3.5 to 4.4)
Cob Color ____________ Maturity White ____________________ Approx. 7 days ltlt B73 _______
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Kernel Traits of GEMS-0002
100 Wt. Avg. 12.5 (10-16)
Color Yellow to Yellow-Orange
Density Avg. 1.35 g/cc
Protein 2.5 pts. gtgtB73
Oil Essentially equal B73

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Recommendations
GEMS-002 is intended as an early Stiff-Stalk
related breeding resource for the improvement
and diversification of elite, non-Lancaster
Sure-Crop related inbreds. The line is unique
in that it has a relatively high proportion of
tropical germplasm yet is able to impart
earliness to hybrids. It has potential as a
source of germplasm in breeding programs
throughout much of the U.S. Corn Belt. Suggest
introduction into breeding programs by crossing
with elite inbreds followed by modified pedigree
selection. Only one cycle of selection has been
practiced there is a need to check disease and
insect resistance.
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Acknowledgments-- Cooperators Linda Pollak
and Kevin Montgomery-- In kind support from
other GEM cooperators-- Technical
staffUSDA/ARS GEM S.C.A. and OARDC provided
funding support.