Location: Sugarcane Field StationTitle: Sugarcane flower behavior and its impact on leaf photosynthesis, canopy reflectance and sucrose yield stability
Submitted to: American Society of Sugar Cane Technologists
Publication Type: Abstract Only
Publication Acceptance Date: 3/31/2022
Publication Date: 7/16/2022
Citation: Rounds, E.W., Zhao, D., Aldrin, M.A., Zhu, K. 2022. Sugarcane flower behavior and its impact on leaf photosynthesis, canopy reflectance and sucrose yield stability. American Society of Sugar Cane Technologists. 42:12-13.
Interpretive Summary: N/A
Technical Abstract: Sugarcane (Saccharum ssp.) is an important cash crop in south Florida with a long harvest season of six months. Better understanding of physiological and yield traits for cultivars with different flowering behaviors as affected by harvest date can improve knowledge. A field study was established at the USDA-ARS Sugarcane Field Station to evaluate growth, physiology, and yield of eight diverse flowering cultivars. The experiment was a complete random block design with three replications. Canopy reflectance, leaf photosynthesis, transpiration, and stomatal conductance were determined during grand growth. Millable stalks were counted in late August. In October through February, 10-stalk bundle samples were collected monthly, weighed for average stalk weight, and milled for juice Brix and POL to estimate sucrose yield (TSH) and its response to harvest date. Averaged across cultivars and three crops (plant cane, two ratoons), TSH was lowest in October and highest in January. Sucrose yield was not associated with flower behavior. Flower behavior, crop, and their interaction were significant (p<0.0003) for normalized difference vegetation index in the red edge (NDVIre). Non-flowering cultivars had greater NDVIre values than early- and late-flowering cultivars. Leaf photosynthesis parameters were significantly influenced by flower behavior (p<0.05) and early flowering cultivars had higher leaf photosynthesis, stomatal conductance, and transpiration than late- and non-flowering cultivars. Early- and late-flowering cultivars had lower NDVIre, but higher photosynthetic parameters than non-flowering cultivars. These results suggest that cultivars with different flowering behaviors may have different physiological approaches to accomplish their final yields.