Losses of sugar content and means to contrast them

A survey has been circulate d within the IIRB, on sugar-content losses in the beet crop during the harvest season. The problem is relevant in some South-European/Mediterranean areas, where it represents a serious constraint to high sugar yields; in North-Central Italy, for instance, it is one of the reasons for an early harvest campaign as the only preventive measure, which in turn limits potential yields. The concerned countries have pointed to several possible causes of variable severity, including biotic (i.e. diseases) and abiotic agents (drought, high temperatures, etc.). In Italy, field-plot trials are aimed at devising a strategy to cope with such losses. In a two-year regional programme, three factors (seed variety, N-fertilization and Cercospora chemical treatments) have been cross-combined, showing specific contributions to mitigate the problem, but a few interactions among them. Further studies have investigated the combination of seed variety and irrigation as possible causal/mitigating agents of sugar-content loss. The experiences, still under way, again seem to point to single effects, instead of an interaction between factors. At last, trials aimed at curbing leaf re-growth late in the season, after severe drought or pest/disease stress, show how some growth regulators in specific applications have exerted a certain influence, but their effectiveness appears to be conditioned by application time and by other unidentified factors. Therefore, it needs to be further investigated, in order to reduce the associated variability and to allow a reliable application