Sugarcane (Saccharum spp.) in south Florida is often subjected to flooding due to interacting
effects of soil subsidence, pumping restrictions, and tropical storms. While there has been
considerable research on the response of sugarcane cultivars to high water tables and
periodic flooding, there is a lack of information on commercial cultivar yield response to
long-term flooding. An experiment was established in Belle Glade, FL to examine the effect
of a 3-month summer flood (July–September) on the growth and yield of cultivars CP 80-1743
and CP 72-2086 during the plant cane (2003) and second ratoon (2005) crop. Harvest samples
were taken early-, mid-, and late-season. Flooding sugarcane in the summer caused
sequentially greater yield reductions throughout the harvest season in plant cane. Sucrose
yields for flooded cane, compared with the non-flooded control, were 9.6 t sucrose ha1
versus 11.7 t sucrose ha1 early, 9.2 t sucrose ha1 versus 12.8 t sucrose ha1 mid-season
and 7.8 t sucrose ha1 versus 12.3 t sucrose ha1 at late harvest. In the second ratoon crop,
flooding reduced sugarcane tonnage and sucrose yield by 54–64% across sampling dates, and
preliminary results indicated that flooding reduced leaf nutrient content by 10–78%. Yield
reductions due to flooding in both crops were attributed more to reduced tonnage rather
than sucrose content. CP 72-2086 yielded 18–28% greater sucrose than CP 80-1743 when
harvested late. However the flood cultivar interaction was not significant as both cultivars
recorded similar yield reductions under flooded conditions. Our results identified severe
yield losses caused by a 3-month summer flood in these cultivars, particularly in ratoon
crops. Strategies to increase summer on-farm water storage in Florida should focus on
short-duration periodic flooding rather than long-term flooding.
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