Although test weight is used as a grading criterion and an indication of quality in wheat (Triticum aestivum L.), its relationship to specific quality parameters in soft wheat is not well documented. Seed characteristics, flour yield, and baking quality were studied in 24 soft red winter wheat (SRWW) genotypes grown in six environments to determine their relationship to test weight. Flour yield, flour protein, alkaline water retention capacity (AWRC), and softness equivalent (SEQ) were evaluated by the micro-procedures of the USDA-ARS soft wheat early-generation milling and baking quality evaluation program. 

Despite removal of shriveled kernels prior to evaluation, environmental effects had a significant impact on quality parameters, ranging from 68% of total variability (SEQ) to 5% (AWRC). Test weight was not correlated with flour yield, but was significantly correlated with flour protein content (r = 0.54, P < 0.05) as was kernel density (r = 0.49). Thousand-kernel weight, diversity of seed size, proportion of large seed, and average kernel length and width were not correlated with flour yield or other quality parameters. Test weight did not predict flour yield in SRWW when shriveling was absent, but it was related to flour protein content, which is associated with baking quality. Kernel size or size distribution did not affect end-use quality. The best predictive model based on the characters above explained little of the total variation in flour yield (R2 = 0.22).