|JOSEPH, RICARDO - Former ARS Employee|
Submitted to: International Sugar Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/28/2011
Publication Date: 3/31/2011
Citation: Reed, S.T., Joseph, R., Ayala Silva, T., Glaz, B.S. 2011. The effects of natural and induced short-term floods on four sugarcane accessions. International Sugar Journal. 113:64-70.
Interpretive Summary: The vast amount of sugarcane cultivated in the Everglades Agricultural Area (EAA) in central Florida made the state the number one sugar producer in the United States. Since the Histosol soils of that region are commonly exposed to a high water table and periodically inundated by floods, a study was conducted to assess the effects of natural and induced short-term floods on sugarcane clones Kewali, Mangwa (Saccharum barberi), Guilini and Kacai (Saccharum sinense). Studied plots were flooded for either four or seven consecutive days then allowed to drain naturally. From selected clones, photosynthesis (Phs), transpiration (Tr) and stomatal resistance (SR) measurements were taken prior to and after flooding. Plot weight, stalk and leaf dimensions, and sugar content were analyzed at harvest. Mangwa, which produced the tallest stalks and the second most stalk numbers, had the greatest TRS (Theoretical Recoverable Sucrose per cane). Brix, Pol and TRS were highest in Mangwa and lowest in Guilin-1 in the plant cane. Plot weight, stalk number and stalk diameter decreased as flood duration increased from zero to seven days. Short term flooding on the four clones studied had lower average individual stalk weights as flood duration increased. Our results showed no direct correlation between photosynthesis and sucrose yield after short term flooding. Theoretical Recoverable Sucrose was also found to increase with flood duration. Sugarcane clones in our study showed only minor responses to the short term flooding compared to flood durations of two months or longer in other studies.
Technical Abstract: A study was initiated at the USDA/ARS Subtropical Horticulture Research Station, Miami, FL to evaluate the potential for flood tolerance in several accessions from Saccharum barberi (Jeswiet) and S. sinense (Roxb. Amend. Jeswiet) sugarcane genera. The experimental design included 4 accessions, Kewali, Mangwa (S. barberi), Guilini, and Kacai (S. sinense). There were two flood durations of 4 or 7 days with non-flooded controls and three replications of each treatment. Photosynthesis (Phs), transpiration (Tr) and stomatal resistance (RS) were measured during the growing season. At harvest plot weight, stalk and leaf dimensions, and sugar content were determined. Photosynthetic rates tended to be higher with the plant cane than the ratoon crop. There were no differences in Phs, Tr and RS between different flood durations for combined data across all sampling dates. However, on days when the cane fields were flooded Phs tended to be lowest with the 7-D flood treatment. The size of the leaves at harvest and the combined Phs rate were not a dominant influence on recoverable sugar per cane and sugar yield for an entire plot. Flood duration had no significant effect on any plant and sucrose content variables. However, plot weight, stalk number and stalk diameter tended to go down as flood duration increased from zero to seven days. Theoretical recoverable sucrose tended to increase with flood duration. In the plant cane, stalk number was the most important determinant of sugar yield. In the ratoon crop, TRS was the most important determinant of sugar yield. Short term floods up to 7 d did not adversely affect single leaf photosynthesis. Differences in photosynthesis did not translate into higher sucrose yield. Sugarcane clones in our study showed only minor responses to the short term flooding compared to flood durations of two months or longer in other studies.