2012 Annual Report
1a.Objectives (from AD-416):
Evaluate and develop germplasm and scientific information that support the use of maize for silage and as a feedstock for biofuel.
1b.Approach (from AD-416):
Three approaches will be used and consist of development of the GEM Quality Synthetic (GQS) population through recurrent selection, development of superior inbreds for silage yield and nutritional attributes through pedigree breeding methods, and identification and release of germplasm with lignocellulosic ethanol potential for use as a biofeedstock. Analytical methods used include conventional silage yield trials and near infrared spectroscopy (NIRS) for silage attributes, and for ethanol measurement.
This project relates to the primary objectives of the parent project which includes the development and evaluation of value-added traits such as silage nutritional quality and yield. Two inbred lines involving GEM germplasm were disclosed for release to the Wisconsin Alumni Research Foundation (WARF). One of the lines was derived from population AR16026:S1719-052 and the other line derived from cycle 0 of the GEM Quality Synthetic (GQS) population which was formed from the intermated populations of CUBA164:S1517 and CUBA117:S1520. The silage nursery was planted on May 12 and May 25 at the UW West Madison Research Station. The GQS synthetic is now at the second cycle of development (GQS C2) and approximately 250 S1’s were planted in the 2012 nursery for per se evaluation and selfing. Advanced lines (S4's) from GQS C1 are also being evaluated this summer for potential release in 2013. Six new GEM releases were introduced to our breeding program in 2012. Five were stiff stalks; GEMS-0218, 0219, 0220, 0222, 0223, and the non-stiff stalk, GEMN-0221. In addition to these populations, seven populations from 2011 will be crossed to a different tester. A set of seven advanced lines from 06GEM05390 (AR16021:S0908a-75-1) and nine lines from GEMS-0183 were selected and are being further evaluated in 2012. The 2012 field trials were planted at two Wisconsin locations, Arlington and Madison, on May 25, and May 30 respectively. Target planting densities were 32,000 plants per acre with three replications per site. Advanced inbreds from families PASCO14:N0424-078-001-B-B (GEMN-0190), SCROGP3:N2017-003-001 (GEMN-0191), SCROGP3:N2017-172-001 (GEMN-0192), and UR11002:N0308b-086-001 (GEMN-0193) are currently being evaluated as top crosses and the lines were selfed and crossed for further testing in 2013, if data from 2012 trials warrants it. Nutritional evaluations will include assessment of neutral detergent fiber (NDF), in vitro true digestibility (IVD), in vitro NDF digestibility (IVNDFD), crude protein (CP), and starch concentration. Based on these values, and milk/ton of forage, milk/acre will be estimated based on the MILK2006 equations (Schwab et al., 2003).