Genotypic and environmental variation for flour swelling volume in wheat

The gelatinization and swelling of wheat (Triticum aestivum L.) starch has an important effect on the quality of end-products, especially white salted noodles. This study was conducted to determine the genotypic and environmental variation for flour swelling volume (FSV) in wheat. FSV was measured for various spring and winter wheat cultivars grown in up to 31 unique environments and up to four crop years. Data were analyzed by organizing the data into eight balanced data sets. FSV ranged from approximate to 19 to 30 mL/g. Analysis of variance (ANOVA) indicated that cultivar was consistently a highly significant source of variation. Environments as unique combinations of locations and crop years were variably significant, as were locations, whereas crop years were always a significant source of variation. Only rarely were ANOVA interaction terms significant. Model R(2) ranged from 0.87 to 0.98 for the eight data sets. Components of variation calculated from ANOVA model and total sums of squares indicated that cultivar accounted for 36.1-93.3% of the total variation. Environments, locations, and years accounted for 1.7-61.7% of the total variation. The relative variation assignable to the interaction of cultivars, environments, locations, or years never exceeded 10%. Penawawa was the highest FSV cultivar and was significantly higher than all other cultivars examined. In conclusion, FSV is highly and primarily influenced by cultivar and secondly by environment, crop year more so than location within a crop year. The small interaction of cultivar with environment suggests that FSV is highly heritable and that cultivar development programs can easily identify and track desirable FSV types. Incremental steps in FSV level were observed among the various cultivars and therefore optimum levels of FSV occurring throughout the range encountered should be attainable in new, improved cultivars.