Location: Sugarcane Field StationTitle: Ratoon stunt disease incidence in the late stages of the Canal Point Sugarcane Cultivar Development Program
|DAVIDSON, WAYNE - Florida Sugarcane League|
|BALTAZAR, MIGUEL - Florida Sugarcane League|
Submitted to: American Society of Sugar Cane Technologists
Publication Type: Abstract Only
Publication Acceptance Date: 4/22/2020
Publication Date: 6/16/2020
Citation: Sood, S.G., Davidson, W., Baltazar, M. 2020. Ratoon stunt disease incidence in the late stages of the Canal Point Sugarcane Cultivar Development Program. American Society of Sugar Cane Technologists. 83(1):16.
Interpretive Summary: N/A
Technical Abstract: The ratoon stunt disease (RSD) caused by the bacterium Leifsonia xyli sub sp. xyli (Lxx) is one of the most economically devastating diseases of sugarcane worldwide. Lxx bacteria colonize xylem cells of the vascular bundles, reducing the flow of nutrients and water from the soil to the leaves, thereby reducing growth. RSD can be managed by growing resistant varieties and by using clean seed cane. Clean seed cane can be obtained either by hot-water treatment or by tissue culture. The late stages, namely Florida sugarcane league (FSCL) increases, of the Canal Point sugarcane cultivar development program are the source of seed cane for commercial plantings. Therefore, it is important to test the varieties in the FSCL increases for the Lxx colonization. 16 varieties in the FSCL increases from 9 locations were sampled in September 2018 and form 6 locations in 2019. Thirty stalks were randomly collected for each variety from each location. Stalks were tested for RSD using standard tissue-blot immunoassay and Lxx colonized vascular bundles (CVB) were counted. The varieties were rated based on average colonized vascular bundles on the rating scale-resistant: 0-2; moderately resistant: 2.1-5; moderately susceptible: 5.1-10.0 and susceptible: over 10 CVB. Most of the varieties in the late stages were resistant or moderately resistant. RSD incidence ranged from 0 to 5.7 CVB in 2018 and 0 to 2.1 CVB in 2019. The highest incidence of RSD was found in CP08-1968 and ranged from 0 to 5.7 CVB at different locations. The adequate level of resistance is available in all the varieties in the late stages. However, the use of disease-free seed cane is still necessary to control the disease. Therefore, it was recommended to growers to use seed cane from the clean fields.