Brown rust, caused by the fungus Puccinia melanocephala, poses an increasing threat to sugarcane industries worldwide. Recently, markers R12H16 and 9020-F4 were developed for a major resistance gene Bru1 that contributes to a significant proportion of brown rust resistance in multiple sugarcane industries. Marker-assisted screening of Louisiana sugarcane germplasm showed a low frequency (4.3%, five out of 117 clones) of Bru1 among sugarcane cultivars and elite breeding clones. Likewise, among progeny of crosses involving wild/exotic germplasm, only 14 of 208 clones (6.7%) tested Bru1 positive. However, Bru1 frequency was higher (28.7%, 52 of 181 clones) in wild/exotic germplasm, which indicated that diverse genetic resources are available for Bru1 introgression. Commercial Bru1-positive cultivar, 'L 01-299', was resistant to brown rust. However, Bru1-positive cultivar, 'L 10-146', was susceptible while Bru1-negative cultivars, such as 'L 99-233', showed resistance to brown rust. Bru1-negative clones with brown rust resistance offer an opportunity to identify alternate sources of resistance, which can be pyramided with Bru1 for effective and durable resistance in sugarcane against the changing pathogen.

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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.