[ Graphics OFF ]
HOME ABOUT US TOUR STAFF LINKS CONTACT US SITE MAP
WHEAT ANALYSIS SYSTEM REGIONAL QUALITY DATA PUROINDOLINE PUBLICATIONS VARIETY QUALITY SCORES BREEDERS LOGIN PNW WQC INFO
Recent Publications
Abstract
Puroindoline Genotype of the U.S. National Institute of Standards & Technology Reference Material 8441, Wheat Hardness Cereal Chem 80:674-678
Morris, C.F. and Massa, A.
USDA-ARS Western Wheat Quality Laboratory - Washington State Univ., Pullman, WA
Grain hardness (kernel texture ) is of central importance in the quality and utilization of wheat (Triticum aestivum L.) grain. Two major classes, soft and hard, are delineated in commerce and in the Official U.S. Standards for Grain. However, measures of grain hardness are empirical and require reference materials for instrument standardization. For AACC approved methods employing near-infrared reflectance (NIR) and the Single Kernel Characterization System (39-70A and 55-31, respectively), such reference materials were prepared by the U.S. Dept. of Agriculture Federal Grain Inspection Service. The material was comprised of genetically-pure commercial grain lots of five soft and five hard wheat varieties, and was made available through the National Institute of Standards and Technology (SRM 8441, ‘Wheat Hardness’). However, since their establishment, the molecular-genetic basis of wheat grain hardness has been shown to result from puroindoline a and b. Consequently, we sought to define the puroindoline genotype of these 10 wheat varieties, and more fully characterize their kernel texture via Particle Size Index (PSI, Method 55-30) and Quadrumat flour milling. NIR, SKCS and Quadrumat break flour yield grouped the hard and soft varieties into discrete texture classes; PSI did not separate completely the two classes. Although all four of these methods of texture measurement were highly inter-correlated, each was variably influenced by some minor, secondary factor(s). Among the hard wheats, the two hard red spring wheat varieties which possess the Pina-D1b (‘a-null’) hardness allele were harder than the hard red winter wheat varieties which possess the Pinb-D1b allele based on NIR, PSI and break flour yield. Among the soft wheat samples, SKCS grouped the eastern soft red winter varieties separate from the western soft white. A more complete understanding of texture-related properties of these and future wheat samples is vital to the use and calibration of kernel texture-measuring instruments.
« Printable Version »
USDA Nondiscrimination Statement | Statements and Disclaimers | WSU Copyright | WSU Disclaimer and Freedom of Information Statement
© 1997 - 2010 USDA/ARS Western Wheat Quality Laboratory - Webmaster