The Eleventh Regional Wheat Workshop For Eastern ... - Cimmyt

Milling and baking quality ofSouth African irrigated wheat cultivars - Mamuya el at.
The main variates which discriminated between interaction effects CVl (x-axis) (Figure 1)
were SDS-sedimentation (r = 0.958), SKCS-HI (r = 0.781), alveograph P/L ratio (r = -0.571)
and vitreous kernels (-0.563), which had the most significant correlation with CV1 scores
(Table 5).
The main variates which discriminated between interaction effects for CV2 (y=axis) (Figure
1 and Table 5) were mixograph development time (r = -0.91), alveograph strength (r = -0.85)
and loaf volume (12% protein) (r = -0.57). The CV2 accounted for 18.7% of the total
variation.
Therefore in conclusion, Figure 1 shows that the pattern for most genotypes within seasons
was very similar. This is shown by codes 2 and 12 (T4), 8 and 16 (SST876), 9 and 17
(SST57),4 and 11 (Kariega), 6 and 14 (SST825), 5 and 15 (SST822), 7 and 18 (Inia), 3 and
10 (Marico). Palmiet (codes 1 and 13) showed unstable quality characteristics. This shows
that despite the environmental conditions having influence on quality parameters, genotype
potential should be the prime objective together with positive environmental interactions. In
ascending order, genotypes like T4;- Palmiet and SST876 had less potential for most of the
parameters, particularly T4 and Palmiet. Nevertheless, Palmiet showed positive
environmental interactions in some locations and it may perform well, also the performance
was intermediate at most of the sites when the environments were not as ideal as it was
during 1997. SST57 showed intermediate potential, whereas Marico, Kariega, SST822,
SST825 and Inia showed intermediate to higher potential. Therefore these genotypes may
give desirable results at most of the sites for various parameters despite seasonal
environmental variations.
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