Location: Sugarcane Field Station2009 Annual Report
1a. Objectives (from AD-416)
1. Develop more efficient breeding and selection methodologies for cultivar development and to produce seed of selected sugarcane germplasm for use in Florida, Louisiana, and Texas. 2. Develop better agronomic practices for the Florida sugarcane industry. 3. Identify alleles or genes that can be used in molecular marker-assisted selection to complement the conventional approach of sugarcane cultivar development. 4. Identify agronomic and physiological relationships of sugarcane with stress tolerance to improve sugarcane cultivar development.
1b. Approach (from AD-416)
Development of new cultivars with disease resistance, freeze tolerance, and high sucrose content will be advanced through genetic and genomics approaches. These will involve the utilization of a sugarcane genetic map with quantitative trait loci (QTL) and the identification of variation in candidate genes through gene expression profiling, and in some cases through developing markers for gene insertions. To improve cultivar development on sand soils, genetic studies will compare selection efficiencies on organic and sand soils and repeatability between selection stages, and agronomic research will seek useful traits for identifying high-yielding genotypes on sand soils. Agronomic research will also seek useful traits for identifying tolerance to shallow water tables on organic soils, and will examine sampling procedures for estimating fiber content.
3. Progress Report
One new sugarcane cultivar, CPCL 99-4455, was recommended for release for commercial production in Florida. The CL in CPCL 99-4455 denotes that the cross from which this cultivar was selected was made in Clewiston, Florida. This is the second cultivar released by this program for which the cross was not made at Canal Point. Production of older cultivars is reduced as new insects, weeds, and diseases, and new races of current diseases continue to appear in Florida. Production remains high across the industry due to the availability of new cultivars with the exception that sugarcane orange rust caused substantial yield losses in fields planted with susceptible cultivars. True seeds, developed from crosses at Canal Point, FL were sent to the ARS cultivar development program in Louisiana, and the Texas A&M program in Texas. About 16,000 seeds from 243 crosses were sent to Texas; about 105,000 seeds from 629 crosses were sent to Louisiana; and about 133,000 seeds from more than 1032 crosses remained in Florida. Cultivars developed from ARS produced seed occupy more than 90% of the sugarcane acreage in Florida, Louisiana, and Texas. This breeding and selection program primarily develops sugarcane cultivars for sand and organic (muck) soils in Florida. In 2009, the second annual meeting was held to report to Florida growers on research to improve cultivar development for sand soils. Presentations reported on research aimed at: 1) improving parental selection for sand soils, 2) determining if an early selection stage should be planted on sand as well as an organic soil, and 3) ability to select 31 genotypes on sand soils. Previous information about these genotypes indicated whether each was expected to yield well on sand only, muck only, or sand and muck. Some changes have already been implemented to improve selection for sand soils. For example, in the final selection stage, one test location with sand soil has been added (new total is three) and one with muck soils has been discontinued (new total is seven). Also, advancements into this stage for muck and sand are now made independently, whereas previously the same genotypes were advanced for both soil types. In an earlier stage, the minimum acceptable sugar content has been lowered for up to five genotypes that have high cane yields. In the 2008/2009 crossing season, about 10% of the total crosses (114) contained at least one parent that has been identified as well adapted to sand. In 2007, a sugarcane rust disease (orange rust) was identified for the first time in Florida. In addition, brown rust has continued to substantially affect sugarcane farmers and the breeding program. For example, in an early selection stage of this program in 2007, only about 300 of 1700 genotypes did not have rust. Currently the program is reviewing options in early selection stages that may result in selection of higher percentages of genotypes that do not have rust. In crosses made this year, 620 had at least one parent resistant to brown rust and 530 had at least one parent resistant to orange rust.
1. Release of High Yielding Sugarcane Cultivar in Florida. New sugarcane cultivars in Florida are continuously needed for sustained or improved yields, resistance to intense disease pressures, and for improved adaptability to freezes and high water tables. Also, higher yields are needed on sand soils which comprise about 20% of Florida’s sugarcane. Through the cooperative efforts of the ARS Sugarcane Field Station, Canal Point, FL; the University of Florida Institute of Food and Agricultural Sciences Everglades Research and Education Center at Belle Glade, Florida; and the Florida Sugar Cane League, Incorporated at Clewiston, Florida, a new sugarcane cultivaras (CPCL 99-4455) was recommended for release in Florida. This new cultivar will add genetic variability for disease resistance while yielding well in Florida, the state in the United States with the highest sugar production; 19% of all sugar produced in the United States. CPCL 99-4455 is expected to yield well on all soils on which sugarcane is produced in Florida.
Milligan, S.B., Davidson, R.W., Edme, S.J., Comstock, J.C., Hu, C.J., Holder, D.G., Glaz, B., Glynn, N.C., Gilbert, R.A. Registration of ‘CPCL 97-2730’ Sugarcane. Journal of Plant Registrations. 3:158-164. 2009.