|DAVIDSON, R WAYNE - FLORIDA SUGARCANE LEAGUE|
|MILLIGAN, SCOTT - MONSANTO CORPORATION|
|HU, CHEN-JIAN - U.S. SUGAR CORPORATION|
|HOLDER, DAVID - U.S. SUGAR CORPORATION|
|GILBERT, ROBERT - UNIVERSITY OF FLORIDA|
|DEL BLANCO, ISABEL|
Submitted to: Journal of Plant Registrations
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/22/2010
Publication Date: 1/12/2011
Citation: Davidson, R., Milligan, S.B., Glaz, B.S., Comstock, J.C., Hu, C., Glynn, N.C., Edme, S.J., Holder, D.G., Gilbert, R.A., Sood, S.G., Del Blanco, I.A., Zhao, D.Registration of ‘CPCL 99-4455’ Sugarcane. Journal of Plant Registrations. 5:54-61. 2011.
Interpretive Summary: Sugarcane is grown on organic (muck) and sand soils in a region near Lake Okeechobee in south Florida. This region contributes about 25% of U.S. domestic sugar production. New cultivars are needed that yield well on both soil types and have acceptable profiles of disease resistance, but only rarely are such cultivars identified. Experimental data of CPCL 99-4455 suggest that it is well suited to the muck soils of this region of Florida. On muck soils, the three-crop mean cane yield of CPCL 99-4455 was similar to that of CP 89-2143. CP 89-2143 was the primary reference cultivar on muck soils against which yields of CPCL 99-4455 were compared. The three-year mean value of sugar content on muck soils was higher for CPCL 99-4455 than for CP 89-2143, both early in the harvest season and averaged across the entire harvest season. Its acceptable cane yield and high sugar content resulted in a sugar per hectare yield and economic index for CPCL 99-4455 on muck soils that were similar to those of CP 89-2143. On sand soils, the sugar content of CPCL 99-4455 was similar to that of CP 78-1628, the reference cultivar for sand soils. However, the cane yield, sugar per hectare yield, and economic index of CP 78-1628 were all significantly higher than those of CPCL 99-4455 on sand soils. Cultivar resistance and tolerance are the major sources of sugarcane disease control in Florida, but they are challenging to identify and quantify, because plants are growing and therefore exposed to disease pressures all year. CPCL 99-4455 has shown adequate resistance for commercial production in Florida to eye spot, leaf scald, smut, brown rust, orange rust, sugarcane mosaic virus, and ratoon stunting. CPCL 99-4455 is susceptible to sugarcane yellow leaf virus as are almost all sugarcane cultivars in Florida. The commercial release of CPCL 99-4455 makes available to Florida growers a cultivar that maintains high yields in the presence of diseases, and therefore should help to continue providing the U.S. an affordable and stable sugar supply. Additionally, CPCL 99-4455 may be tested by farmers in Central America, who grow mostly Canal Point (CP) cultivars. For more than 30 years, one public and one private program developed new sugarcane cultivars for Florida. In 2004, the private program of United States Sugar Corporation, located in Clewiston (CL), FL, was discontinued and much of their genetic material was donated to a cooperative program located at a USDA-ARS facility in Canal Point (CP), FL where ARS, University of Florida, and Florida Sugar Cane League, Inc. scientists cooperate in the development of new sugarcane cultivars. When it was donated to the CP (public) program, the name of CL 99-4455 was changed to CPCL 99-4455. CPCL 99-4455 was released in October 2009.
Technical Abstract: Sugarcane grown in a concentrated region near Lake Okeechobee in Florida produces 25% of the sugar produced in the U.S. The development of a constant supply of new sugarcane cultivars helps growers to respond to economic, pathological, and ecological pressures. The objectives of this research were to test yields and disease resistance of 13 new sugarcane genotypes in the plant-cane, first-ratoon, and second-ratoon crops in ten commercial sugarcane fields in Florida. CPCL 99-4455, an outstanding genotype in these tests, was first selected in a private program conducted by the United States Sugar Corp. (USSC) from the progeny of a cross between USSC proprietary genotype CL 90-4643 (female flower) x cultivar CP 84-1198 (male flower). CP 84-1198 first reached 1.0 % of the commercial sugarcane area in Florida in 1996 and it peaked at 5.1% in 2002. The private breeding program at USSC was discontinued in 2004 and CPCL 99-4455 was donated to a public program located at the USDA-ARS facility at Canal Point, FL. Final testing of CPCL 99-4455 was then accomplished through cooperative research of this public program conducted by the USDA-ARS, the University of Florida-Institute of Food and Agricultural Sciences, and the Florida Sugar Cane League, Inc., and CPCL 99-4455 was released in October 2009. In experiments on organic (muck) soils, yields of CPCL 99-4455 were compared with yields of cultivars CP 72-2086 and CP 89-2143. On sand soils, CPCL 99-4455 yields were compared with those of cultivar CP 78-1628. The mean stalk weights of CPCL 99-4455, CP 72-2086, and CP 89-2143, were 1.4, 1.6, and 1.4 kg, respectively on muck soils; and the stalk weights of CPCL 99-4455 and CP 78-1628 were 1.0 and 1.2 kg, respectively, on sand soils. Yields of commercially recoverable sucrose (CRS) on muck soils for CPCL 99-4455, CP 72-2086, and CP 89-2143 were 127.1, 119.4, and 119.9 g sucrose per kg cane, respectively. Cane yields on muck soils for CPCL 99-4455, CP 72-2086, and CP 89-2143 were 124.7, 122.2, and 128.9 tons per ha, respectively; and sucrose yields on muck soils were 15.85, 14.59, and 15.46 kg per ha, respectively. On sand soils, CRS yields for CPCL 99-4455 and CP 78-1628 were 134.2 and 131.0 g per kg, respectively. Cane yields on sand soils for CPCL 99-4455 and CP 78-1628 were 79.6 and 113.7 tons per ha, respectively; and sucrose yields on sand soils were 10.69 and 14.90 tons per ha, respectively. CPCL 99-4455 has shown adequate resistance to all the major sugarcane diseases in Florida except sugarcane yellow leaf virus. Based on its high sugar and tonnage yields on muck soils, as well as its high CRS throughout the harvest season, and its disease resistance, CPCL 99-4455 may make a substantial commercial contribution to sugarcane production in Florida.