|LABORDE, CHRIS - Florida Crystals Corporation|
|HU, CHEN-JIAN - Us Sugar Corporation|
Submitted to: International Society of Sugar Cane Technologists Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: 6/20/2012
Publication Date: 9/12/2012
Citation: Zhao, D., Glaz, B.S., Comstock, J.C., Laborde, C., Hu, C. 2012. Growth and Yield Performances of Two Sugarcane Genotypes on Sand Soils. International Society of Sugar Cane Technologists Proceedings. pp 38.
Technical Abstract: Approximately 20% of sugarcane in Florida grows on sand soils. Water deficit during the sugarcane formative growth phase may limit growth and yield on the sand soils. Identification of useful physiological and growth traits may help scientists select sugarcane genotypes with stress tolerance and improve selection efficiency for sand soils. Greenhouse and field studies were conducted to examine physiological and growth traits of sugarcane on sand soils. The greenhouse study included two water regimes [well watered (WW) and water deficit stress (WS)] and two genotypes (CP 80-1743 and CP 01-2390). All pots were well watered until 58 days after planting, when water was withheld from the WS pots. The WS significantly decreased leaf photosynthetic rate, green leaf area, stalk height, large tillers, and shoot biomass. Although leaf photosynthetic rate did not differ statistically between genotypes, CP 01-2390 had significantly greater leaf area, more large tillers, longer stalks, and greater shoot biomass than CP 80-1743 under both the WW and WS conditions. In field studies at two locations with sand soils, leaf photosynthetic rates of CP 01-2390 and CP 80-1743 were 33.9 and 29.9 µmol/m-2/s-1, respectively. CP 01-2390 (34.1 Mg/ha) had a 53% higher sucrose yield (TSH) than CP 80-1743 (22.3 Mg/ha). Increased TSH for CP 01-2390 was mainly associated with higher cane tonnage rather than commercial recoverable sucrose (CRS). Number of harvestable stalks, mean stalk weight, and stalk length contributed to the higher cane tonnage. When plants matured, the stalk population of CP 01-2390 was 20% greater, its mean stalk length was 18% longer, and the stalk weight was 30% greater compared with those of CP 80-1743. Stalk diameter and CRS did not differ between the two genotypes. These results suggest that selection for high stalk number (many tillers) and increased leaf area during early growth can help identify sugarcane genotypes with improved cane yields on sand soils.