|SINGH, MANNINDER - University Of Florida|
|LABORDE, CHRIS - Us Sugar Corporation|
Submitted to: Sugar Journal
Publication Type: Abstract Only
Publication Acceptance Date: 5/13/2016
Publication Date: 6/13/2016
Citation: Zhao, D., Singh, M., Laborde, C. 2016. Growth, Physiological and Yield Responses to the Mid-Season Application of Moddus for Seed Cane Quality in Sugarcane. Sugar Journal. 2016 79:16-18.
Technical Abstract: Moddus is a plant growth regulator for sugarcane (Saccharum spp.) and has been used to produce high quality of seed cane in Florida by reducing internode length, mitigating plant lodging, and facilitating harvest in addition to commonly using as a ripener for improving sucrose content. But little is known if application of Moddus in the mid season affects plant physiological function and final yield. A study was conducted at the USDA-ARS Sugarcane Field Station, Canal Point, Florida to investigate responses of sugarcane growth, physiology, and yield components to Moddus applications in the mid-growing season and to determine if there were any differences in plant response to Moddus among sugarcane cultivars. Three cultivars (CP 00-1101, CP 01-1372, and CP 05-1526) were used in this study. Moddus was applied two times in a rate of 6 oz/A with 50 gallons of water each time at 149 and 215 days after planting. Growth and physiological measurements were taken biweekly from the first time of Moddus application through 4 weeks after the second time of application. Yield data were collected in mid-December. Cultivar and Moddus interactions were significant in leaf SPAD reading, stalk weight, cane yield, commercial recoverable sucrose (CRS), and sucrose yield. Moddus increased the SPAD reading of CP 01-1372 and CP 05-1526, but did not affect that of CP 00-1101. Leaf photosynthesis did not respond to Moddus, but the Moddus treatment had significantly lower normalized difference vegetation index (NDVI, an indicator of canopy ground cover or closure) than the untreated check. Stalk length of the Moddus treated plants was 8-10% shorter than check. Moddus slightly decreased sucrose yield of CP 00-1101, but increased sucrose yield of CP 05-1526 due to higher stalk weight and CRS. Results indicated that Moddus application for seed cane will depend on sugarcane cultivars.