Estimates of genetic variances and derived statistics of pertinent traits are essential for efficient plant breeding programs. For clonal sugarcane (Saccharum spp.) populations in Louisiana, such estimates (and unconfoanded estimates of genotype by environment [GE] and genotype by crop [GC] variances) were lacking. The objectives of this study were to estimate broad‐sense genetic and GE variance components for a clonal sugarcane population representative of initial stages of replicated testing and to determine the relative importance of years, locations, and crops. Thirty‐seven genotypes were planted in 1983 and replanted in 1984 in replicated tests at five locations. Data from two 3‐yr. crop cycles were used. Genetic advance (GA) indicated considerable improvement potential in sucrose yield, cane yield, and stalk number and weight. Genotypic variance was generally secondary to error variance in determining phenotypic variance; GE variances were tertiary to genotypic and error variances. Within a crop, genotype by location (GL) variances tended to be larger than genotype by year (GY). Estimates of potential of plant cane sucrose yields over years and locations implied testing across locations could substitute for years, effectively reducing the time to identify elite clones. Analysis across crops showed GC, GL and GYL interaction variances were usually larger than GY. Estimates of GA showed no difference in potential gain from replicating across years vs. crops. For several traits, the most potential for improvement is in older crop performance, and selection is best practiced with regard to crop.

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‘L 79‐1002’ (Reg. No. CV‐132, PI 651501) sugarcane (a complex hybrid of Saccharum officinarum L., S. spontaneum L., S. barberi Jeswiet, and S. sinense Roxb. amend. Jeswiet) was released on 26 Apr. 2007 by the Louisiana State University Agricultural Center in cooperation with the USDA‐ARS and the American Sugarcane League, Inc. The cross for L 79‐1002, a F1 hybrid, was made in 1974 using ‘CP 52‐68’ as the female parent and Tainan, a S. spontaneum clone, as the male parent. Initial clonal selection was done in single stools. Testing was done from 1976 through 1983 in yield trials conducted in the traditional sugarcane growing area in south Louisiana and in the colder, non‐sugarcane growing regions of north Louisiana. Yield testing was resumed in 2002 through 2005 as interest in biofuels research renewed. L 79‐1002 was released for an emerging biofuels industry because of its high fiber content and biomass (cane yield) potential. Average fiber content for L 79‐1002 is approximately 257 g kg−1 The new cultivar also has excellent vigor and ratooning ability. Experiments conducted at Bossier City, Louisiana (32.1° N lat) indicated a broader range of adaptability than sugarcane cultivars grown for the production of sucrose.

Genetic correlations are commonly considered in the development of selection strategies. Previously reported correlations between sugarcane (Sacdmrum spp.) yield components may be of questionable value because they were obtained either from small populations or from a restricted range of environments. The effect of crop age on trait relationships has not been reported. Thistady's objective was to examine crop age effects on the geneticorrelations among sugarcane traits using path coefficient analysis. A population was planted in 1983 and 1984 at five locations in Louisiana. Harvest data were collected for three crops. Results indicated that cane yield (TCH) was the most important determinant of sucrose yield (SPH) and became increasingly important in determining the SPH in older ratoon crops (rsph,tchh = 0.91). Stalk number (SNO) was the primary determinant of TCH and became more important in determining TCH in older ratoon crops (rtch,sno = 0.77). Stalk diameter (DIA) was more important than stalk length (LEN) and stalk density (DEN) in affecting stalk weight (WT) regardless of crop age (rwt,dla = 0.70 vs. rwt,len = 0.52 and rwtden = 0.33). Brix and juice parity were highly correlated with sucrose content and with each other, and were not affected by crop age. The results indicated that selection for SPH should emphasize TCH with concentration on SNO, particularly in ratoon crops. The results also indicated that development of selection strategies of sugarcane should consider crop age in weighing the importance of yield components that affect SPH.

PI 699125) sugarcane (an interspecific hybrid of Saccharum spp.) was released on 10 Apr. 2019 for commercial production in the Louisiana sugar industry. L 12-201 was derived from a cross between the female parent 'L 97-128' and the male parent 'HoCP 96-540'. Early-stage selection through the seedling and two unreplicated clonal stages by researchers at the Louisiana State University Agricultural Center culminated in the assignment of a permanent varietal designation in 2012. Thereafter, the experimental variety was further evaluated cooperatively with personnel from the USDA-ARS at Houma and the American Sugar Cane League, Inc., at Thibodaux, LA, through several stages at multiple locations. In the final testing stage, data were collected from 60 replicated, combine-harvested trials at 12 representative light-and heavy-textured soil locations. Averaged across the plant-cane crop, the sucrose content, cane yield, and sugar yield were significantly (P < .05) higher in L 12-201 than in 'L 01-299', the most widely grown cultivar in the Louisiana sugar industry. In the first-and second-ratoon crops, L 12-201 had significantly (P < .05) less cane yield and sugar yield than L 01-299, but sucrose content was not significantly different between L 12-201 and L 01-299. When averaged across the light-textured versus heavy-textured soil locations, no significant differences in performance were found for L 12-201 in any of the traits measured. The new cultivar had a lower stalk population and greater stalk weight compared with L 01-299, especially in the ratoon crops. L 12-201 is a mid-maturing cultivar. Whenever possible, L 12-201 should be harvested before the arrival of subfreezing temperatures because it is among the least cold tolerant cultivars in the industry. L 12-201 is resistant to sorghum mosaic, smut, leaf scald, and ratoon stunt; moderately resistant to brown rust; and susceptible to yellow leaf and the sugarcane borer.

‘L 99‐226’ (Reg. No. CV‐138, PI 655533) sugarcane (a complex hybrid of Saccharum officinarum L., S. barberi Jeswiet, S. spontaneum L., and S. sinense Roxb. amend. Jeswiet) was released on 25 Apr. 2006 by the Louisiana State University Agricultural Center (LSU AgCenter) in cooperation with the USDA–ARS and the American Sugar Cane League, Inc. L 99‐226 was released because of its high sugar and cane yields along with excellent sucrose content. Data from 93 outfield trials indicate that L 99‐226 produced approximately 33% greater sugar yield and 9% greater sucrose content than ‘LCP 85‐384’ when averaged across all crops. The new cultivar is moderately resistant to brown rust disease (Puccinia melanocephala H. and P. Sydow), mosaic diseases, and the sugarcane borer (Diatraea saccharalis F.) and moderately susceptible to smut (Ustilago scitaminea Sydow & P. Sydow) and leaf scald [Xanthomonas albilineans (Ashby) Dowson]. The cross for L 99‐226 (XL94‐128) was made in fall 1994. Early stage clonal selection was done as single stools in 1996 followed by first clonal line trial selection in 1997 and second clonal line trial stage selection in 1998. Testing in replicated yield trials was conducted throughout the sugarcane growing area in south Louisiana from 2000 through 2005. Plant patent no. 18,807 was issued for L 99‐226 on 13 May 2008.

‘L 01–283’ (Reg. No. CV‐140, PI 658001) sugarcane (a complex hybrid of Saccharum officinarum L., S. barberi Jeswiet, S. spontaneum L., and S. sinense Roxb. amend. Jeswiet) was released on 6 May 2008 by the Louisiana State University Agricultural Center in cooperation with the USDA‐ARS and the American Sugarcane League, Inc. L 01–283 was released because of its high sugar and cane yields, early maturity, and excellent ratooning ability. Cumulative data indicated that L 01–283 produced 10% higher sugar yield, 5% higher cane yield and 4% higher sucrose content than ‘HoCP 96–540’ when averaged across all crops. The new cultivar is moderately resistant to common brown rust disease (caused by Puccinia melanocephala Syd. & P. Syd.), resistant to smut disease (caused by Ustilago scitaminea Syd. & P. Syd.), resistant to leaf scald [caused by Xanthomonas albilineans (Ashby) Dowson], resistant to mosaic strains, and moderately resistant to the sugarcane borer (Diatraea saccharalis F.). The cross for L 01–283 (XL96–402) was made on 22 October 1996. Early stage clonal selection was done as single stools in 1998 followed by the first clonal line trial selection in 1999 and the second clonal line trial selection in 2000. Testing in replicated yield trials was conducted throughout the sugarcane growing area in south Louisiana from 2002 to 2008.

‘L 01–299’ (Reg. No. CV‐141, PI 659071) sugarcane (a complex hybrid of Saccharum officinarum L., S. barberi Jeswiet, S. spontaneum L., and S. sinense Roxb. amend. Jeswiet) was released on 28 Aug. 2009 by the Louisiana State University Agricultural Center in cooperation with the USDA‐ARS and the American Sugarcane League, Inc. L 01–299 was released because of its high sugar and cane yields, erectness, and excellent ratooning ability. The cross for L 01–299 (XL96–402) was made on 22 Oct. 1996. Early‐stage clonal selection was done as single stools in 1998 followed by selection in the first clonal line trials in 1999, selection in the second clonal line trials in 2000, and permanent cultivar assignment in 2001. Testing in replicated yield trials was conducted throughout the sugarcane‐growing area in south Louisiana from 2002 to 2008. Cumulative data indicated that L 01–299 had a 14% higher sugar yield, 13% higher cane yield, and 1% higher sucrose content than ‘HoCP 96–540’ when averaged across all crops. The new cultivar is resistant to common brown rust disease (caused by Puccinia melanocephala Syd. & P. Syd.), susceptible to smut disease (caused by Ustilago scitaminea Syd. & P. Syd.), moderately resistant to leaf scald [caused by Xanthomonas albilineans (Ashby) Dowson], resistant to mosaic strains, and moderately resistant to the sugarcane borer (Diatraea saccharalis F.).