Wednesday, November 15, 2006
248-8

Genetic Variation for Gluten Strength and Water Holding Capacity in a Soft Winter Wheat Population.

Carrie Knott, University of Kentucky, 1405 Veterans Road Room 310, Lexington, KY 40546-0312, David Van Sanford, Univ. of Kentucky-Plant & Soil Sciences Dept, 327 Plant Science Bldg., Lexington, KY 40546-0312, and Edward Souza, 1680 Madison Ave, USDA-ARS Soft Wheat Quality Lab, USDA-ARS Soft Wheat Quality Laboratory, Williams Hall, Wooster, OH 44691-4096.

Most soft wheat (Triticum aestivum L.) breeding programs make selections based upon agronomic characters such as yield, test weight, height, heading date and pest resistance.  In advanced generations, once agronomically acceptable lines have been identified, grain is analyzed for milling and baking quality characteristics.  In soft wheat, these quality characteristics can differ substantially based upon the end-product.  Typically, a low water holding capacity is desirable for both cookies and crackers while elevated gluten strength is desirable for crackers. Early generation lines are not typically evaluated for these traits because flour-based tests require too much grain and there are too many lines to screen efficiently.  However, meal-based micro-tests have been developed to determine water holding capacity and gluten strength.  Wheat meal sodium carbonate solvent retention capacity (SRC) has been found to be negatively correlated with water holding capacity (and thus, cookie diameter) and wheat meal SDS sedimentation is positively correlated with gluten strength.  These tests require very small samples: SRC requires 5 g and SDS sedimentation utilizes 1 g. Thus, these quality tests can be incorporated into breeding programs for early generation selection of quality attributes.  The objective of this study was to characterize a set of recombinant inbred lines from a strong gluten soft red winter wheat x weak gluten soft white winter wheat cross for water retention capacity and gluten strength as indicated by wheat meal sodium carbonate SRC and wheat meal SDS sedimentation, respectively.  Sodium carbonate SRC data from one location in 2005 ranged from 78 to 106 % of meal weight, while SDS sedimentation values ranged from 5.2 to 17 mL.  These preliminary data indicate significant variation for the traits in this population.  Replicated data from two locations in 2006 will be presented; genetic parameters, including heritability, will be estimated.