Analysis of differences in yield between six sugar‐beet varieties

SUMMARY The basis of differences in yield between six sugar‐beet varieties was studied by measuring the changes in their leaf areas and dry weights throughout the season. Initially, dry‐matter production was determined by the rate at which leaf area developed, but this effect did not persist to final harvest. Varieties that maintained the largest net‐assimilation rates in September produced largest sugar yields. Characteristically, these varieties showed the smallest losses in lamina dry weight through leaf senescence late in the season, and put the largest proportion of their photosynthate into root production.