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 wh ite salted noodles. This study was conducted to determine the genotypi c 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 ran ged from approximate to 19 to 30 mL/g. Analysis of variance (ANOVA) in dicated that cultivar was consistently a highly significant source of variation. Environments as unique combinations of locations and crop y ears 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 mo del and total sums of squares indicated that cultivar accounted for 36 .1-93.3% of the total variation. Environments, locations, and years ac counted for 1.7-61.7% of the total variation. The relative variation a ssignable to the interaction of cultivars, environments, locations, or years never exceeded 10%. Penawawa was the highest FSV cultivar and w as significantly higher than all other cultivars examined. In conclusi on, 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 hi ghly heritable and that cultivar development programs can easily ident ify 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.