Mexican rice borer control tactics in United States sugarcane

Authors: Showler, Allan

Submitted to: Insect Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/3/2019
Publication Date: 6/5/2019
Citation: Showler, A. 2019. Mexican rice borer control tactics in United States sugarcane. Insect Science. 10(6):160. https://doi.org/10.3390/insects10060160.
DOI: https://doi.org/10.3390/insects10060160

Interpretive Summary: The Mexican rice borer moved from Mexico into South Texas in the early 1980s; by 2008 the pest was found in sugarcane- and rice-growing areas of East Texas and Louisiana, and by 2012 it was reported on grassy weeds in Florida. Because insecticides and biological control agents were unsuccessful, those tactics were discontinued, and infestations of sugarcane have not been suppressed. During the last 15 years, however, research has focused on the pest’s ecology, improved insecticides and scouting methods, identification of sugarcane resistance mechanisms, and new cultural tactics. A surveillance technique was developed that indicates when larvae are most vulnerable to insecticide sprays. Some relatively new insecticides have shown promise, including an insect growth regulator. Potentially useful cultural practices have been revealed, including plowing under fallow stubble, judicious use of fertilizer, adequate irrigation, avoiding growing sugarcane close to Mexican rice borer-susceptible maize cultivars, and enhancement of natural enemy populations. Demonstrated and potentially useful sugarcane resistance mechanisms involve physiochemical attributes, physical characteristics, and transgenic cultivars.

Technical Abstract: The invasive Mexican rice borer, Eoreuma loftini (Dyar), expanded its range from Mexico to South Texas in the early 1980s and by 2008 the pest moved into sugarcane- and rice-growing areas of East Texas and Louisiana, and by 2012 was reported on noncrop host plants in Florida. Efforts to suppress E. loftini in United States sugarcane with chemicals and biological control agents were unsuccessful, both tactics were discontinued, and E. loftini infestation of sugarcane has continued unchecked. During the last 15 years, however, research has focused on the pest’s ecology, improved insecticides and scouting methods, identification of sugarcane resistance mechanisms, and new cultural tactics. A surveillance technique was developed that indicates when larvae are most vulnerable to insecticide sprays. Currently registered insecticides for E. loftini control are not widely applied against E. loftini although some show promise, including an insect growth regulator. A number of potentially useful cultural practices are available, including plowing under fallow stubble, judicious use of fertilizer, adequate irrigation, avoiding proximity to E. loftini-susceptible maize cultivars, and enhancement of natural enemy populations. Demonstrated and potentially useful sugarcane resistance mechanisms involve physiochemical attributes, physical characteristics, and transgenic cultivars.