Location: Sugarcane Field StationTitle: Evaluation of Leaf scald Resistance in CP Clones
|DAVIDSON, WAYNE - Florida Sugarcane League|
|BALTAZAR, MIGUEL - Florida Sugarcane League|
|PACHTER, NICHOLAS - University Of Florida|
Submitted to: American Society of Sugar Cane Technologists
Publication Type: Abstract Only
Publication Acceptance Date: 3/31/2022
Publication Date: 7/16/2022
Citation: Sood, S.G., Davidson, W.R., Baltazar, M., Pachter, N. 2022. Evaluation of Leaf scald Resistance in CP Clones. American Society of Sugar Cane Technologists. 32-33.
Interpretive Summary: N/A
Technical Abstract: Leaf Scald caused by Xanthomonas albilineans (Ashby) Dowson is one of the major diseases for sugarcane production. The most economical management of leaf scald is growing resistant cultivars. Therefore, the Canal Point breeding and cultivar development program (CP Program) selects clones based on artificial inoculation and natural infection. In 2011, the CP Program was separated into the muck soil (organic) and sand soil (mineral) programs. Since 2014, clones in the Stage 3 increases, and Stage 4 in both muck and sand soils are screened for leaf scald resistance. From 2014 to 2021, 551 clones consisting of released varieties, commercial reference cultivars, and test clones were screened for natural infection at seven muck soil locations and three sand soil locations. These clones had 172 female parents and 160 male parents. The data was collected as the number of stools showing leaf scald symptoms per plot. The clones with no stools with leaf scald were considered resistant; clones with 1 to 5 stools infected with leaf scald were considered moderately resistant; clones with 6 to 10 stools infected with leaf scald were considered moderately resistant, and any clone with more than 10 stools infected with leaf scald was considered susceptible. The data show that 40% of the screened clones had at least one stool with leaf scald symptoms, however, only 4% of the clones were susceptible. Sixty percent of the clones were resistant, 32% moderately resistant, and 4% moderately susceptible. The Eastgate location has the highest level of leaf scald infected stools followed by Wedgworth, and only one stool was infected at Okeelanta. Clones on muck soil had significantly more infected stools than clones on sand soils. More stools were infected in 2020 and 2021 than in other years. These findings are important to improve the breeding and selection process as well as for the evaluation of variation in the pathogen.