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a USDA-ARS Sugarcane Field Station, 12990 US Hwy. 441 N, Canal Point, FL 33438
b Florida Sugar Cane League, Inc., P.O. Box 1208, Clewiston, FL 33440
c Univ. of Florida, Everglades Res. and Educ. Ctr., 3200 East Palm Beach Rd., Belle Glade, FL 33430. Mention of trade names or commercial products is solely for the purpose of providing specific information and does not imply recommendation or endorsement by USDA, the University of Florida, or the Florida Sugar Cane League, Inc
* Corresponding author (Barry.Glaz{at}ars.usda.gov).
ABSTRACT
‘CP 00-2180’ (Reg. No. CV-134, PI 654093) sugarcane (a complex hybrid of Saccharum spp.) was developed through cooperative research conducted by the USDA-ARS, the University of Florida, and the Florida Sugar Cane League, Inc., and was released to growers in Florida in September 2007. CP 00-2180 was selected from a self-cross of cultivar HoCP 91-552 made at Canal Point, FL, in January 1998. Based on its high cane yields and fiber content (16%), HoCP 91-552 was released as a cultivar for bioenergy in Louisiana. CP 00-2180 was released and recommended for sand soils in Florida because of its high plant cane and acceptable ratoon per hectare yields of cane and sucrose and commercial recoverable sucrose on sand soils, and its resistance to smut [caused by Ustilago scitaminea (Sydow & P. Sydow)], brown rust (caused by Puccinia melanocephala H. & P. Sydow), orange rust (caused by Puccinia kuehnii E.J. Butler), leaf scald [caused by Xanthomonas albilineans (Ashby) Dowson], Sugarcane mosaic virus strain E, and ratoon stunting disease (caused by Clavibacter xyli subsp. xyli Davis) in Florida.
Abbreviations: CP, Canal Point • CP program, Canal Point sugarcane cultivar breeding and selection program • CRS, commercial recoverable sucrose • RSD, ratoon stunting disease
‘C P 00-2180’ (Reg. No. CV-134, PI 654093) sugarcane (a complex hybrid of Saccharum spp.), a product of a long-term recurrent selection program conducted through cooperative research of the USDA-ARS, the University of Florida, and the Florida Sugar Cane League, Inc., was released in Florida in September 2007. From 1968 to 2000, the Canal Point sugarcane cultivar breeding and selection program (CP program) contributed to significant gains in Florida sugarcane yields, primarily through genetic improvements in allocation of assimilates to sucrose accumulation (Edmé et al., 2005). However, these yield improvements were primarily on the muck, rather than the sand soils on which sugarcane is grown in Florida. Approximately 79% of Florida's 163,000 ha of sugarcane were muck soils and 21% were sand soils in 2006 (Glaz, 2007). The CP program is conducting research aimed at comprehensively reviewing its breeding and selection practices to improve genotype selection for sand soils. Recent results of research that focused only on the final selection stage of the CP program recommended changes that would improve selection for sand soils without impacting negatively on selection for muck soils and without increasing resources (Glaz and Kang, 2008).
New sugarcane cultivars are needed in Florida as sources of resistance to numerous diseases and protection against new virulent races or strains. For example, several major CP cultivars have become susceptible to rust in the last 20 yr, leading to their withdrawal from commercial production. A major complication regarding breeding for rust resistance in Florida is that, although highly heritable (Comstock et al., 1992; Ramdoyal et al., 2000), it is not durable, probably due to the formation of new rust races (Shine et al., 2005). Similar challenges with new races are expected from orange rust (caused by Puccinia kuehnii E.J. Butler), which until recently was not present in Florida (Comstock et al., 2008).
CP 00-2180 was released because of its high plant cane and acceptable ratoon per hectare yields of cane and sucrose and commercial recoverable sucrose (CRS) on sand soils, as well as its acceptable profile of resistance or tolerance to the major and minor sugarcane diseases in Florida. The name CP 00-2180 was assigned according to routine Canal Point naming protocol. The name indicates assignment in the year 2000 (CP 00) as the 1180th selection in the first clonal selection stage which contained about 15 000 genotypes. Selection numbers of <1000, 1000 to 2999, and >3000 are reserved for genotypes resulting from CP seed that are selected in Louisiana, Florida, and Texas, respectively.
CP 00-2180 was selected from the self-cross ‘HoCP 91-552’ made at Canal Point, FL in January 1998. Based on its high cane yields and high fiber content (16%), HoCP 91-552 was released for use as a source of bioenergy in Louisiana (T. Tew, personal communication, 2007). The pedigree of CP 00-2180 includes CP genotypes as well as HoCP, LCP, F, and Co genotypes that were developed by breeding programs in Houma, LA (located at a USDA-ARS facility), Baton Rouge, LA (located at Louisiana State University), a discontinued University of Florida program, and a program in Coimbatore, India, respectively. Among the genotypes in the pedigree, ‘CP 70-1133’ (Rice et al., 1978) was widely planted in Florida and ‘CP 65-357’ (Breaux et al., 1974) was widely planted in Louisiana. CP 70-1133 was a great grandparent and CP 65-357 was a great-great grandparent. Both CP 65-357 and CP 70-1133 were widely planted on sand soils in Florida before they became susceptible to brown rust (caused by Puccinia melanocephala H. & P. Sydow).
Methods
Early Selection Stages
CP 00-2180 was selected through standard selection procedures of the CP program (Table 1
). The self-cross (X97-0268) of HoCP 91-552 was made at Canal Point in January 1998. The F1 seeds were planted in flats in a greenhouse early in 1999 and were transplanted in May 1999 to the field at Canal Point with approximately 100,000 genotypes in the seedling stage. Beginning at this stage, the CP program propagates genotypes clonally. One stalk from the stool that was to become CP 00-2180 was selected and advanced to Stage 1 in January 2000 with about 15,000 other unreplicated selections. Stage-1 plots were one row 0.5 m long and were separated by 0.5-m alleys. Row spacing in Stage 1 and in all subsequent selection stages was 1.5 m. Selections in Seedlings and Stage 1 were made on the basis of visual criteria. Emphasis was placed on vigor and resistance to diseases (primarily brown rust, smut [caused by Ustilago scitaminea (Sydow & P. Sydow)], and leaf scald [caused by Xanthomonas albilineans (Ashby) Dowson]) by natural infection.
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Stalks were counted in Stage 2 in July and August 2001. In October 2001, 10-stalk samples were collected from each plot, weighed, and milled. To estimate cane yield, stalk weight was multiplied by stalk number. Stalks were milled to extract juice and determine theoretical recoverable sucrose, which was calculated as described by Legendre (1992). Fiber in this formula was estimated as 10% for all genotypes in Stages 2 and 3 and estimated as described below in Stage 4. All values of theoretical recoverable sucrose were multiplied by 0.86 to approximate CRS. Similarly, Legendre (1992) reported the calculation of a liquidation factor (ranging from 0.83 to 0.90) that was used by commercial mills in Louisiana to convert theoretical recoverable sucrose to CRS. Theoretical economic index (profitability) was calculated using a procedure that integrates sucrose content with costs of harvesting, hauling, and milling the cane (Deren et al., 1995).
Yields and disease reactions were the major selection criteria in Stage 2 (and later in Stages 3 and 4). Cane yield, production of sucrose, and profitability were the key yield criteria. Resistance to diseases in Stage 2 focused on brown rust, smut, Sugarcane mosaic virus strain E (mosaic), and leaf scald. Sucrose yield (Mg ha–1) was calculated as
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Yield Trials in Commercial Fields
From Stage 2, 135 genotypes were advanced to Stage 3 in November–December 2001. Stage-3 genotypes and two reference cultivars (CP 70-1133 and CP 72-2086) were planted in yield trials in commercial fields at four grower farms representative of the Florida sugarcane industry. Farms A. Duda & Sons', Inc., Okeelanta Corporation, and Sugar Farms Cooperative North–Osceola Region had organic (muck) soils, and Hilliard Brothers' of Florida, Ltd., had a sand soil. Each Stage-3 trial had two replications of genotypes planted in a randomized complete block design in plots with two rows 4.5 m long. Plots were arranged in tiers containing 10 plots that were two plots long, each separated by a 1.5-m alley. Adjacent tiers were separated from each other by a 6.0-m alley. Data were collected in the plant-cane (October 2002) and first-ratoon (October 2003) crops. Estimates of cane and sucrose yields and profitability were determined as described for Stage 2. On the basis of per hectare cane and sucrose yields, profitability, and resistance to brown rust, leaf scald, mosaic, and smut, CP 00-2180 was among 14 genotypes advanced from Stage 3 to Stage 4 in November 2003.
The 14 Stage-4 genotypes, including CP 00-2180, were planted in yield trials within commercial fields at nine grower farms in November–December 2003 and two additional farms in August and November 2004. These included five trials at the same four farms used for Stage 3 (two trials planted at Okeelanta Corporation) plus four more locations with organic soils (Eastgate Farms, Inc., Knight Management, Inc., Sugar Farms Cooperative North–SFI Region, and Wedgworth Farms, Inc.), and two more locations with sand soils (Lykes Brothers', Inc., and United States Sugar Corporation–Townsite). Reference cultivars used in Stage-4 trials were CP 72-2086, CP 78-1628 (Tai et al., 1991), and CP 89-2143 (Glaz et al., 2000). CP 89-2143 was the primary reference cultivar for trials planted on organic soils, but comparisons were also made with CP 72-2086. CP 78-1628 was the primary reference cultivar for trials planted on sand soils. All trials had six replications with the exception of the trial at Townsite, which had three. Genotypes were planted in randomized complete block designs in plots three rows wide and 10.5 m long. Alleys of 1.5 m separated plots. Trials were generally 2 plots wide (six rows) and 48 plots long. For the nine Stage-4 trials planted in 2003, cane tonnage was estimated by first counting stalks in the two interior rows of each plot from July through September in 2004 (plant cane), 2005 (first ratoon), and 2006 (second ratoon). Stalk weight and CRS were estimated as described for Stage 2 from 10-stalk samples. There was one sample date per crop cycle at each location, from October through March of 2004–2005 (plant cane), 2005–2006 (first ratoon), and 2006–2007 (second ratoon). For the two Stage-4 trials planted in 2004, these same procedures were followed 1 yr later.
The fiber from sugarcane stalks is used to generate electricity for sugarcane mills and sugar refineries. However, excessive fiber can delay the milling process. Using five-stalk samples collected from border rows from 2004 through 2007, 17 fiber estimates were made for CP 00-2180. Each estimate was from a five-stalk sample collected from Stage-4 border rows. Leaves were stripped from these stalks, which were then cut into three approximately even sections (bottom, middle, and top stalk sections). Two randomly selected bottom, middle, and top sections were processed through a Jeffco cutter-grinder (Jeffries Brothers, Ltd., Brisbane QLD, Australia). About 75 g of material (fresh bagasse) processed through the cutter-grinder was collected and weighed. These fresh bagasse samples were then placed in cloth bags and washed twice in cold water in a washing machine to remove soluble solids. Samples were then dried at 63°C until their weights stabilized. The fiber percentage of a genotype was calculated as
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Samples of a reference cultivar were processed on all dates that fiber samples of CP 00-2180 were processed. All fiber percentages calculated on a given day were corrected to the historical fiber percentage of the reference cultivar. For example, the reported fiber percentage of CP 89-2143 was 9.85%. On days when CP 89-2143 was the reference cultivar when fiber samples were processed, if its estimated fiber was 10.00% then all estimated fiber samples of other genotypes were multiplied by 0.985.
Characterization by Microsatellite Genotyping
Twelve pairs of microsatellite primers (Table 2
) developed through the International Consortium of Sugarcane Biotechnology (Cordeiro et al., 2003) were used to generate a genetic fingerprint for CP 00-2180. Isolation of DNA was accomplished as described by Glynn et al. (2008), and microsatellite amplification was performed according to procedures described by Edmé et al. (2006). The genetic fingerprint for CP 00-2180 was compared with those of cultivars CP 70-1133, CP 72-2086, CP 78-1628, CP 80-1743 (Deren et al., 1991), CP 88-1762 (Tai et al., 1997), and CP 89-2143. These six cultivars occupied 86% of the sugarcane acreage in Florida in 2006 (Glaz, 2007). A binary matrix for presence and absence of fragments among CP 00-2180 and the six widely planted cultivars was generated and used to produce genetic distance indices and a phenetic tree using Treecon Version 1.3b (Van de Peer and De Wachter, 1994). Distance estimations were performed using Nei and Li (1979) methods with bootstrap analysis (1000 iterations), and a phenetic tree inferred using unweighted pair group method with arithmetic mean (UPGMA) clustering.
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Characteristics
Field Performance
CP 00-2180 was tested extensively throughout the Florida sugarcane industry. Thirty harvests from 11 trial locations were conducted in Florida during 2004–2005 (nine plant-cane harvests), 2005–2006 (two plant-cane harvests and nine first-ratoon harvests), and 2006–2007 (one first-ratoon and nine s-ratoon harvests). CP 00-2180 had high yields of sucrose relative to the reference cultivars in the plant-cane crop on sand (Table 3
) and organic (Table 4
) soils. For the mean of the three-crop cycle, stalk weights of CP 00-2180 were higher than those of the reference cultivar (CP 78-1628) on sand soils and both reference cultivars (CP 72-2086 and CP 89-2143) on organic soils. Fiber content of CP 00-2180 was 9.46%.
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The mean sucrose yield of CP 00-2180 on sand soils was significantly higher than that of CP 78-1628 in the plant-cane crop. Sucrose yields of CP 00-2180 and CP 78-1628 were similar in both ratoon crop cycles and for the mean of all three crop cycles. The theoretical economic index of CP 00-2180 was significantly higher than that of CP 78-1628 for the mean of the three crop cycles as well as for the plant-cane crop. In the two ratoon crops, CP 00-2180 and CP 78-1628 had similar economic indices.
CP 00-2180 had acceptable cane yields on organic soils, where its mean cane yield was significantly higher than that of CP 72-2086, the secondary reference cultivar on organic soils, in all three crop cycles (Table 4). However, the cane yield of CP 00-2180 was significantly lower than that of CP 89-2143, the primary reference cultivar on organic soils, in the second-ratoon crop; and both cultivars had similar cane yields for the mean of the three-crop cycle. The CRS values of CP 00-2180 were significantly lower than those of CP 89-2143 in all three crop cycles and were significantly lower than those of CP 72-2086 in the plant-cane crop, but otherwise, CP 00-2180 and CP 72-2086 had similar CRS values.
The sucrose yields of CP 00-2180 on organic soils were significantly higher than those of CP 72-2086 except in the first-ratoon crop. The sucrose yield and economic index of CP 00-2180 were significantly lower than those of CP 89-2143 in the second-ratoon crop cycle; otherwise, these two cultivars had similar sucrose yields and economic indices on organic soils.
In the CP sugarcane cultivar development program in Florida, decisions to advance genotypes from Stages 2 and 3 and recommendations to release Stage-4 genotypes are made by a committee of sugarcane farmers and representatives from public and private organizations. Members of this committee considered all yield and disease information, along with their individual visual ratings of CP 00-2180 in seed cane (seed cane is the term used to describe stem sections that are used to vegetatively propagate sugarcane) expansion fields, and in June 2007, they recommended to release CP 00-2180 for use on sand soils in Florida due to its high yields of cane and sucrose and its acceptable profile of resistance or tolerance to major and minor sugarcane diseases typically encountered on sand soils in Florida. CP 00-2180 was not recommended for commercial use on organic soils in Florida because of its low CRS values on these soils.
Agronomic, Botanical, and Molecular Descriptions
Plants described here were characterized on 29 to 31 Jan. 2008, approximately 350 d after emergence in field plantings on a muck soil at Canal Point, FL (Table 5
). The stalks characterized were from inner rows protected from direct sunlight unless otherwise noted. Colors were determined from Munsell Color Charts for Plant Tissues, and botanical descriptions were based on terminology of Artschwager and Brandes (1958). Under different environmental and cultural conditions, color and other phenotypic expressions may vary in sugarcane cultivars.
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Stalk heights in mature stalks of CP 72-2086, CP 89-2143, and CP 00-2180 were measured from the ground to the top visible dewlap. Dewlaps form the hinge of the blade joint in sugarcane. CP 00-2180 exhibited a mean stalk height of 325 cm. The mean heights of CP 72-2086 and CP 89-2143 were 343 and 305 cm, respectively. Mean internode length, at the 9th through 11th internodes from the ground, of CP 00-2180 was 15.1 cm compared with 14.6 cm for CP 72-2086 and CP 89-2143. Stalk diameter was measured at the middle of the 3rd (low) and 10th (middle) internodes from the ground as well as at the middle of the hardened internode closest to the top visible dewlap (upper). The mean low, middle, and upper stalk diameters of CP 00-2180 were 29.6, 25.7, and 21.8 mm, respectively. These compared with low, middle, and upper diameters of CP 72-2086 of 33.0, 28.4, and 22.7 mm, respectively, and CP 89-2143 diameters of 30.0, 25.7, and 22.6 mm, respectively. CP 00-2180 exhibited a cylindrical-shaped internode at the 10th internode from the ground and a glabrous growth ring with a mean width of 3.4 mm. The root band of CP 00-2180 was 5.5 mm wide and exhibited unequally distributed rows of circular primordia with diameters ranging from 2.0 to 3.0 mm. The root band was widest around the bud and had no wax layer. Bud furrows were absent from the internodes of CP 00-2180. CP 72-2086 and CP 89-2143 exhibited moderate bud furrows. The buds of CP 00-2180 and CP 72-2086 were located within the root band, whereas the buds of CP 89-2143 extended into the leaf scar. The buds of CP 00-2180 were green yellow (2.5GY 8/6). Buds of all three cultivars were raised above the surface of the root band. CP 00-2180 exhibited roundish buds with crawfish-type wings at the 10th internode compared with the squarish pentagonal buds with wing inserted high of CP 72-2086 and the round buds with central germ pores of CP 89-2143. The bud width of CP 00-2180 (5.6 mm) was less than the widths of CP 72-2086 (6.5 mm) and CP 89-2143 (6.3 mm). The bud length of CP 00-2180 was 5.6 mm compared with bud lengths of CP 72-2086 (6.2 mm) and CP 89-2143 (6.0 mm). None of these cultivars exhibited pubescence on the buds.
The canopy of CP 00-2180 was curved compared with the erect leaves of CP 89-2143 and the ascending leaves with drooping tips of CP 72-2086. The mean leaf blade lengths and widths of CP 00-2180, CP 72-2086, and CP 89-2143 at the top visible dewlaps were 139 and 4.5 cm, 110 and 3.4 cm, and 123 and 3.3 cm, respectively. Leaf sheaths had tufts of pubescence. Leaf sheaths on younger leaves were green yellow (2.5GY 8/4) and on older leaves were yellow (2.5Y 8/4). CP 00-2180, CP 72-2086, and CP 89-2143 leaves exhibited raised midribs on their abaxial sides. The midrib of CP 00-2180 was 5.3 mm wide on the adaxial side, where the leaf was 24.0 mm wide. Midrib widths on the adaxial sides of CP 72-2086 and CP 89-2143 were 9.0 and 6.2 mm, respectively, and leaf widths of CP 72-2086 and CP 89-2143 were 27.1 and 24.9 mm, respectively. The midrib of CP 00-2180 was the same color as the leaf blade on the abaxial side. On the adaxial side, the midrib of CP 00-2180 was white. The dewlaps on mature plants of CP 00-2180 were two shades of yellow (2.5Y 6/2 and 2.5Y 5/2), and their shape was squarish deltoid. The auricle shapes for CP 00-2180 were deltoid on one side and straight transitional on the opposite side. The auricles of CP 89-2143 were lanceolate on one side and deltoid on the opposite side, and the auricles of CP 72-2086 were deltoid on both sides. Auricle lengths, measured about five nodes below the top visible dewlap for CP 00-2180, CP 72-2086, and CP 89-2143 were 7, 4, and 5 mm, respectively. The ligules of CP 00-2180 exhibited a broad subarcuate shape compared with the broad crescent shapes of ligules of CP 72-2086 and CP 89-2143. The ligule length of CP 00-2180 was approximately 3.0 mm compared with CP 72-2086 (5.8 mm) and CP 89-2143 (6.0 mm). Ligules of CP 00-2180 were yellow (5Y 8/2) and had tufts of pubescence on their edges. In the most recent flowering season, CP 00-2180 flowered in the third week of January.
Twelve microsatellite primer pairs amplified 148 fragments, ranging from 105 to 380 bp, in CP 70-1133, CP 72-2086, CP 78-1628, CP 80-1743, CP 88-1762, CP 89-2143, and CP 00-2180 (Table 2). Of these fragments, 125 were polymorphic and 23 were monomorphic. Unique fragments were identified for each cultivar, but there were also some overlapping fragments. The number of fragments amplified in CP 00-2180 ranged from 4 to 10. The resulting phenetic tree illustrates that CP 00-2180 is genetically distinct from the six other cultivars (Fig. 1 ). The 12 microsatellite primers used and the resulting genetic fingerprints may provide useful information for identifying these seven cultivars in the future.
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When CP 00-2180 was in Stage 2, it showed no symptoms after field inoculations were conducted to determine its susceptibility to eye spot [caused by Bipolaris sacchari (E.J. Butler)]. Eye spot is not a commercial problem in Florida. Field inoculations with smut were also conducted on CP 00-2180 during the years it was in Stages 3 and 4. Susceptibility to smut in inoculated tests was determined by comparing the number of sori produced by CP 00-2180 with those produced by cultivars CP 73-1547 (Miller et al., 1982) and CP 78-1628. Smut susceptibilities of CP 73-1547 and CP 78-1628 are at the upper limits of acceptability for commercial production in Florida. Based on 0 whips for CP 00-2180, 0 whips for CP 78-1628, and 16 whips for CP 73-1547 during 2 yr of testing, and based on 0 stools infected with smut due to natural infection in Stage-4 plots, CP 00-2180 was classified as resistant to smut in Florida.
Greenhouse inoculations were conducted with leaf scald (3 yr) and mosaic (2 yr) when CP 00-2180 was in Stages 3 and 4. The number of infected CP 00-2180 plants with leaf scald was compared with the number of infected plants of CP 80-1743. For mosaic, the numbers of infected plants of CP 00-2180 and CP 72-2086 were compared. CP 80-1743 susceptibility to leaf scald and CP 72-2086 susceptibility to mosaic are at the upper limits of acceptability for commercial sugarcane production in Florida. In the first year of inoculated tests, 16.7% of CP 00-2180 plants were infected with leaf scald compared with 21.4% for CP 80-1743. In the second year of leaf-scald inoculations, percentages of infected plants were 3.8 and 50.6 for CP 00-2180 and CP 80-1743, respectively; and in the third year, percentages were 4.5% infected for CP 00-2180 and 14.3% for CP 80-1743. Three stools of CP 00-2180 were found naturally infected with leaf scald in seed-cane increase plots. Thus, CP 00-2180 was classified as moderately resistant to leaf scald in Florida. CP 00-2180 had 0 plants infected in inoculation tests with mosaic in each of 2 yr compared with 19 and 70.3% infected plants of CP 72-2086. Based on these inoculated tests and natural infection evaluations, CP 00-2180 was classified as resistant to mosaic in Florida.
Ratoon stunting disease susceptibility has no level at which commercial production is not acceptable because it can be controlled by use of noninfected planting material. Inoculation tests for RSD susceptibility of CP 00-2180 were conducted from 2001 through 2004. CP 00-2180 was considered resistant to RSD because its mean number of colonized vascular bundles (1.4) in these tests was substantially lower than the overall mean number of vascular bundles (9.5) for CP 72-1210 (Miller et al., 1981) and ‘CP 80-1827’ (Glaz et al., 1990), both of which are considered moderately susceptible.
Cold Tolerance
To assess cold tolerance, Stage-4 genotypes, CP 72-2086, and CP 89-2143 were subjected to freezing temperatures in two field experiments established at the University of Florida–Institute of Food and Agricultural Sciences Hague research facility near Gainesville, FL. CP 00-2180 along with 13 other Stage-4 genotypes, CP 72-2086, and CP 89-2143 were planted on 22 Feb. 2005 as two randomized complete block experiments with four replications in single-row plots. Plots were 1.5 m long and 2.4 m apart with 2.4-m breaks between replications. Freezing temperatures between 0 and –3°C were recorded 1, 10, 7, 8, and 1 d in the following November and December (2005), and January, February, and March (2006), respectively. Five-stalk samples were cut for analyses of sucrose content on 13 and 27 Jan. and 15 Mar. 2006. Cold-tolerance rankings were based on temporal deterioration of juice quality in mature stalks after exposure to freezing temperatures. Rankings from 1st to 16th signified best to worst cold tolerance. CP 00-2180 ranked 16th among 16 genotypes for cold tolerance. CP 72-2086 and CP 89-2143 ranked 12th and 3rd for cold tolerance, respectively.
Availability
In its initial year of release, seed cane of CP 00-2180 will be available from the Florida Sugar Cane League, Inc., for commercial planting in areas where sugarcane is grown on sand soils in Florida. It is not anticipated that patent protection for CP 00-2180 will be sought. Small quantities of seed cane for research purposes may be obtained at the USDA-ARS Sugarcane Field Station, Canal Point, FL, where CP 00-2180 will be maintained for at least 5 yr from the date of this publication.
Acknowledgments
The authors acknowledge Ron Rice of the Palm Beach County Extension Service for his contributions to this registration.
Footnotes
All rights reserved. No part of this periodical may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, or any information storage and retrieval system, without permission in writing from the publisher. Permission for printing and for reprinting the material contained herein has been obtained by the publisher.
Received for publication May 17, 2008.
References
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