DIFFERENCES IN ACCUMULATION OF STORAGE PROTEINS BETWEEN WHEAT CULTIVARS DURING DEVELOPMENT

The concentration and composition of storage proteins in the developin g kernels of five different wheat cultivars were investigated. The pla nts were grown in solution culture under strictly controlled condition s in climatic chambers and with long-term limitation of external nitro gen availability. Thus, by growing these cultivars under the same defi ned treatments, reliable differences in the storage protein developmen t could be determined. The total protein concentration was assayed usi ng an automatic nitrogen analyser. The storage protein composition was examined by acidic polyacrylamide gel electrophoresis and sodium dode cyl sulphate polyacrylamide gel electrophoresis from 6 to 58 days afte r anthesis. The results showed that, in all stages of plant developmen t, the ranking of the cultivars as to the storage protein concentratio n was the same as for mature field-grown kernels. The differences in t he storage protein concentration between the cultivars could not be ex plained by differences in protein composition. The start of storage pr otein formation during plant development did not differ between the te sted cultivars, as determined by the electrophoresis pattern. The diff erences in the storage protein concentration between cultivars most li kely depends on the relative balance between starch and nitrogen depos ition in the grain, during the whole grain filling period.