A A C C   2 0 0 0   A n n u a l   M e e t i n g

Grain endosperm hardness is an important parameter largely applied in prediction of breadmaking quality of common wheat (Triticum aestivum L.) with regard to milling, baking and biscuit products processing. In 1996-1998, the Perten Instruments firm kindly analysed a set of Czech and Slovak wheat genotypes for grain hardness using a SKCS 4100 instrument. During the three-year period, the set consisted of 70 samples when individual genotypes were in three- and two-year replications. The genotypes were also analysed for volume weight, falling number, protein and wet gluten content, SDS-sedimentation test, gluten index, swelling and rheological measurements using a farinograph and alveograph. Obtained results were subjected to statistical evaluation by analysis of variance, correlation and cluster analyses. The analysis of variance showed highly significant effects of both weather conditions of the year and the cultivar (P=0.01) on grain endosperm hardness at a slightly dominating effect of the cultivar (year 42%, cultivar 51%) that indicates genetic determination of grain endosperm hardness in wheat. Based on a correlation analysis, the closest correlation (at P=0.01) was assessed between grain hardness and water absorption capacity. Another significant correlations at the same level of significance were found for dough elasticity, dough development time, and sedimentation test. Based on results of genotypic differences obtained by analysis of variance and cluster analysis the analysed wheat genotypes were classified according to different grain endosperm hardness.