Use of Gem Germplasm for Evaluation and Development of Drought Tolerance, Corn Earworm (Cew) Resistance, and Low Aflatoxin Level Grain Corn
North Central Regional Plant Introduction Station, Ames, Iowa
2011 Annual Report
1a.Objectives (from AD-416)
Evaluate GEM breeding crosses and develop germplasm for abiotic (drought and heat) and biotic stress (CEW and aflatoxin) tolerance; select, advance and release inbred lines from breeding crosses containing GEM germplasm.
1b.Approach (from AD-416)
GEM germplasm will be evaluated for abiotic and biotic stress tolerance under controlled irrigation management. Top crosses will be made with the most tolerant inbreds and yield trials conducted. Evaluation will be conducted for CEW, and aflatoxin level, and the most resistant sources advanced by inbreeding. New exotic breeding crosses will be evaluated to identify and prioritize for future breeding under abiotic and biotic stress conditions.
The specific objectives of this project include selection and development of inbred lines with abiotic stress resistance including drought, heat, corn ear worm (CEW) resistance, and the evaluation of new breeding crosses. Approximately 100 testcrosses between GEM lines (developed in Lubbock) were evaluated for grain yield, CEW, and drought tolerance (using controlled irrigation) at three locations in the Texas High Plains. Three GEM derived lines were entered in the Texas State silage trials in 2011. Work continues on the brown midrib lines derived from GUAT209:N1925 (bm1) and DK888:N11 (bm3) and these lines are now being further advanced by inbreeding, and top crosses are being made for silage yield trials in 2012. Three testcrosses of GEM lines were included in the SERAT (multistate aflatoxin trials) in 2011. Twenty new GEM breeding crosses are being evaluated for drought, CEW, and agronomic performance in Lubbock. The methods for monitoring activities include (1) observing germplasm developed by the Cooperator and (2) progress reports submitted by the Cooperator in July and December for the Annual GEM Cooperator Meeting. E-mail exchanges were periodically initiated by the ADODR or Cooperator on status of experiments during the growing season, and availability of new germplasm provided by the Authorized Departmental Officer's Designated Representative (ADODR) to the Cooperator. Top crosses and drought resistant inbreds developed by the Cooperator have been planted in the GEM Field Day demonstration plot in 2011.