Author
Grisham, Michael | |
Warnke, Kathryn | |
Maggio, Jeri |
Submitted to: American Society of Sugar Cane Technologists
Publication Type: Abstract Only Publication Acceptance Date: 4/15/2015 Publication Date: 6/1/2015 Citation: Grisham, M.P., Warnke, K.Z., Maggio, J.R. 2015. Effect of Sugarcane Mosaic caused by Sorghum mosaic virus on sugarcane in Louisiana. Journal of the American Society of Sugar Cane Technologists. 35:48. Interpretive Summary: Technical Abstract: Sugarcane mosaic is caused by two viruses, Sugarcane mosaic virus (SCVM) or Sorghum mosaic virus (SrMV). In Louisiana, SrMV is the predominant mosaic pathogen affecting sugarcane. In a field experiment established in 2012, plots were planted with seed cane with or without mosaic symptoms. The mosaic was determined to be caused by SrMV. The experiment included one released (Ho 05-961) and four near-release sugarcane varieties (Ho 09-832, HoCP 09-804, L 08-88, and L 09-117). Percent shoots with mosaic symptoms was determined in the spring, while the number of millable stalks and average stalk heights were determined in the late summer for each plot. Stalk heights were also measured in late summer. The plant-cane and first-ratoon crops of the experiment were harvested with a single-row, chopper harvester in 2013 and 2014, respectively; and the total plot weight determined with a single-axle wagon equipped with load cells. A billet sample was collected from each plot for juice quality analysis. Cane and sucrose yields were calculated using plot weights and theoretically recoverable sucrose (TRS). The average cane yield was numerically lower among all treatment plots planted with virus-infected seed cane in plant-cane and first-ratoon crops except for those in the first-ratoon crop of Ho 05-961. On the other hand, average TRS was numerically higher in all treatment plots planted with virus-infected seed cane. Average sucrose yield was lower in plots planted with virus-infected seed cane compared to those planted with symptom-free seed cane in plant-cane (24%) and first–ratoon (27%) crops of L 08-88, respectively. Sucrose yield reduction in other cultivars was less than 5% except for a reduction of 16% in the first-ratoon crop of HoCP 09-804. In plant cane, the average percent shoots with mosaic symptoms among plots of the five cultivars planted with mosaic symptomatic seed cane ranged from 28% for HoCP 09-804 to 97% for L 08-88, and from 4-32% among the plots planted with symptom-free seed cane. Field spread of the mosaic viruses is common, particularly in the spring. Slight to moderate increases in percent shoots with mosaic symptoms was noted in the first-ratoon crop for both disease treatments except in L 09-117 where the incidence was less in the first-ratoon crop. In previous research, recovery of mosaic virus infection was observed among some cultivars. Mosaic continues to be a disease with the potential to cause economic losses in sugarcane. |