Association of cold tolerance and stem borer resistance in sugarcane cultivars

Authors: Penn, Hannah; Hale, Anna; Todd, James

Submitted to: Entomological Society of America, Southwestern and Southeastern Branch
Publication Type: Abstract Only
Publication Acceptance Date: 1/17/2025
Publication Date: N/A
Citation: N/A

Interpretive Summary: Louisiana is the coldest sugarcane-growing location in the world, and as such, the use of cold tolerant cultivars is necessary particularly to prevent degradation of sugar content following early freezes. Within Louisiana growing regions, the most economically damaging insect pests of sugarcane are stem borers like the sugarcane borer (SCB) and the Mexican rice borer (MRB) which are also managed, in part, with the use of resistant cultivars. Prior work has indicated that there may be a potential correlation between cold tolerance and stem borer resistance, so we conducted a review of commercially released US cultivars and used multiple correspondence analysis to assess the association of these traits. We then evaluated the potential contribution of total fiber content as a mechanism underlying this association. Finally, we assessed SCB larval performance on select cultivars differing in SCB resistance and cold tolerance levels. While we found that SCB and MRB resistance was associated with good cold tolerance in both Louisiana and Florida-developed cultivars, this did not appear to be mediated by fiber content since fiber was only correlated with borer resistance but not cold tolerance. As this was unexpected, we separated these cultivars by origin for reassessment. Further, we did not see any significant differences in SCB larval performance between cultivars varying in either trait. These data indicate that breeding for both stem borer resistance and cold tolerance may be possible given the robust relationship between them. However, further evaluation of potential mechanisms is required before more targeted breeding can occur.

Technical Abstract: Louisiana is the coldest sugarcane-growing location in the world, and as such, the use of cold tolerant cultivars is necessary particularly to prevent degradation of sugar content following early freezes. Within Louisiana growing regions, the most economically damaging insect pests of sugarcane are stem borers like the sugarcane borer (SCB) and the Mexican rice borer (MRB) which are also managed, in part, with the use of resistant cultivars. Prior work has indicated that there may be a potential correlation between cold tolerance and stem borer resistance, so we conducted a review of commercially released US cultivars and used multiple correspondence analysis to assess the association of these traits. We then evaluated the potential contribution of total fiber content as a mechanism underlying this association. Finally, we assessed SCB larval performance on select cultivars differing in SCB resistance and cold tolerance levels. While we found that SCB and MRB resistance was associated with good cold tolerance in both Louisiana and Florida-developed cultivars, this did not appear to be mediated by fiber content since fiber was only correlated with borer resistance but not cold tolerance. As this was unexpected, we separated these cultivars by origin for reassessment. Further, we did not see any significant differences in SCB larval performance between cultivars varying in either trait. These data indicate that breeding for both stem borer resistance and cold tolerance may be possible given the robust relationship between them. However, further evaluation of potential mechanisms is required before more targeted breeding can occur.