Among the 13 quality parameters measured, no differences (P>0.05) occurred between club and lax NILs for kernel hardness, ash content, flour protein, water absorption, cookie diameter or cookie score. There were significant (P<O.05) differences between the club and lax NILs for flour yield, break flour yield, milling score, wheat protein, mixing type, cake volume and cake score for one or both years or for one or both populations (Table 1). In 1995 the club and lax NILs differed for break flour yield, wheat protein and cake score but only for one of the two populations (Table 1). In 1996 the dub and lax NILs differed for mixing type and cake volume for the Early Blackhull/7*Paha population; they differed for flour yield, break flour yield and milling score for both populations (Table 1). When averaged across both years, the club and lax NILs differed for mixing type in Early Blackhull/ 7*paha and for cake score in Suweon 185/7*Paha. Club and lax NILs differed only for three traits of both populations when averaged across years. These were flour yield, break flour yield and milling score (Table 1). In all instances where differences occurred between quality traits of club and lax NILs, the lax sibs consistently had a more optimal value than did the club sibs. Generally the means of the four club and four lax NILs of both populations had similar quality trait values to Paha. The only exception was the mean of common NILs of Suweon 185/7*Paha exceeded Paha for milling score.

These results were somewhat unexpected. In the U.S. Pacific Northwest soft white winter club cultivars generally have better soft wheat quality than common soft white winter cultivars. This is especially true for milling quality. In this study the C allele for dense spike of Paha failed to enhance flour yield, break flour yield and milling score. Conversely the lax spike c allele may enhance these three quality traits. Differences also occurred between club and lax sibs for mixing type and cake score but not in both populations. Hence it is unlikely that there is a direct effect between the C locus and these two traits.

Among the eight agronomic traits measured the club and lax NILs differed (P<O.05) for kernel weight, kernels per spike, and percent lodging in both populations (Table 2). Club NILs averaged 19% more kernels per spike, with kernels that were 7 to 14% lighter than their lax sibs. They also sustained about 25% less lodging than their lax sibs. Lax NILs of the Suweon 185/7*Paha population were significantly taller (P<O.05) than their club sibs. Club NILs of Early Blackhull/7*Paha headed 1d later (P<O.05) than their lax types. They also headed 1d later in the Suweon 185/7*Paha population but this difference was not significant (P>O.05).

These results agreed in part with those of Gul and Allan (1972a, b). They found that club NILs had increased kernels per spike, decreased kernel weight and reduced plant height compared to their lax sibs in a Suweon 92/8*Omar population. They reported that club NILs had increased grain yields and test weights compared to their lax sibs whereas no differences occurred for these two traits in this study.

The C allele in the earlier and in this study was derived from Omar. Paha is a backcross-derived club cultivar, selected from a Suweon 92/4*Omar population. Paha and Omar differ mainly in plant height. Paha is a semidwarf cultivar while Omar is a tall, non-semidwarf cultivar. In this study the club and lax NILs were semidwarfs while in the Gul and Allan (1972a) study they were tall, non-semidwarfs. Perhaps semidwarf versus non- semidwarf plant height determines whether the C allele affects certain traits such as grain yield and test weight.

Acknowledgments

The author thanks the Washington Wheat Commission for providing partial support of the research and to the USDA-ARS Western Wheat Quality Laboratory of Pullman, Washington, for performing the quality evaluations.

References

AACC. (1995) Aproved methods of the American Assoc of Cereal Chemists. 9th ed. American Assoc. Of Cereal Chemists, St. Paul, Minnesota.

Gul A and Allan RE (1972a) Relation of the club gene with yield and yield components of near-isogenic wheat lines. Crop Sci 12: 297-301.

Gul A and Allan RE (1972b) Relation of the club gene to culm length and other characters of near-isogenic wheat lines. Crop Sci 12: 310-313.