Effect of cultivar, sowing date, and harvest date on yields and sugar contents of beet on a dry land site in Canterbury

Abstract

Vytomo sugar beet and Yellow Daeno and Monoblanc fodder beets were sown on 23 September, 19 October, and 23 November 1979, and harvested at 4-weekly intervals from December 1979 to September 1980. The September sowing gave higher sugar yields than the October sowing, until April. The November sowing gave sugar yields about 2.5 t/ha less than the October sowing for all harvest dates. Sugar yields increased until July, initially because of increases in root fresh-weight and, to a lesser extent, root dry matter (DM)%. However, after May, increases mainly resulted from higher sugar content of root DM. Sugar in the roots was practically all sucrose until the September harvest, when total sugar yields fell but the proportion of reducing sugars increased. Monoblanc fodder beet gave the highest sugar yields, particularly later in the season. Top fresh-weights declined throughout the autumn and winter, but increased again in late August-September. Maximum leaf area indices (LAI) were low, and were achieved about 4 months after sowing. Monoblanc had the highest LAI.

Keywords:

• sugar beet
• fodder beet
• Beta vulgaris
• cultivars
• yields