West Indian Canefly (Hemiptera: Delphacidae): An emerging pest of Louisiana sugarcane

Authors: WILSON, BLAKE - LSU Agcenter; BEUZELIN, J - University Of Florida; Richard, Randy; Johnson, Richard; GRAVOIS, KENNETH - LSU Agcenter; WHITE, WILLIAM - Retired ARS Employee

Submitted to: Journal of Economic Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/23/2019
Publication Date: 11/21/2019
Citation: Wilson, B.E., Beuzelin, J.M., Richard, R.T., Johnson, R.M., Gravois, K.A., White, W.H. 2019. West Indian Canefly (Hemiptera: Delphacidae): An emerging pest of Louisiana sugarcane. Journal of Economic Entomology. 113(1):263-272. https://doi.org/10.1093/jee/toz284.
DOI: https://doi.org/10.1093/jee/toz284

Interpretive Summary: The West Indian canefly was an occasional pest of sugarcane in Louisiana for many years, but has recently emerged as a more consistent threat with outbreaks occurring in 2012, 2016, and 2017. Insect surveys of commercial fields in 2016 revealed that West Indian canefly infestations were present throughout the Louisiana sugarcane industry and that populations peaked in mid-June before declining. High minimum winter temperatures are generally associated with West Indian canefly outbreaks. We evaluated six insecticides for their potential control of the pest. Four of these insecticides demonstrated effective control of the West Indian canefly; including, '-cyhalothrin, flupyradifurone, acetamiprid, and imidacloprid. In five of the six insecticide trials, the West Indian canefly infestations had substantially declined by 21 days after treatment. In one of four small plot trials in which we collected yield data, insecticide treatment also showed a positive effect on sugar yields. Insecticide treatment also increased yield in one of two large plot trials conducted in 2012. Linear regression revealed that West Indian canefly cumulative insect days in a grid sampling study were inversely associated with sugar yields. Results from these collective experiments suggest impacts on sugar yields are influenced by pest density and infestation duration. Visual ratings of sooty mold coverage revealed a range of susceptibility among 33 sugarcane genotypes. The research presented here documents the impact of the West Indian canefly to Louisiana sugarcane and provides important groundwork for developing effective pest management strategies. Future research efforts should aim to identify ecological factors influencing population dynamics, varietal preferences, and economic thresholds.

Technical Abstract: The West Indian canefly, Saccharosydne saccharivora (Westwood) (Hemiptera: Delphacidae), is a sporadic pest of sugarcane in Louisiana which has recently emerged as a more consistent threat with outbreaks occurring in 2012, 2016, and 2017. Surveys of commercial fields in 2016 revealed that S. saccharivora infestations were present throughout the Louisiana sugarcane industry and that populations peaked in mid-June before declining. High minimum winter temperatures are generally associated with S. saccharivora outbreaks. Six insecticide evaluations demonstrated effective control can be achieved with several insecticides including '-cyhalothrin, flupyradifurone, acetamiprid, and imidacloprid. In five of the six insecticide trials, S. saccharivora infestations had substantially declined by 21 days after treatment. Effects of insecticidal control of S. saccharivora on sugar yields were detected in one of four small plot trials in which yield data were collected. Insecticide treatment increased yield in one of two large plot trials conducted in 2012. Linear regression revealed S. saccharivora cumulative insect days in a grid sampling study were inversely associated with sugar yields. Results from these collective experiments suggest impacts on sugar yields are influenced by pest density and infestation duration. Visual ratings of sooty mold coverage revealed a range of susceptibility among 33 sugarcane genotypes. The research presented herein documents the impact of S. saccharivora to Louisiana sugarcane and provides important ground work for developing effective pest management strategies. Future research efforts should aim to identify ecological factors influencing population dynamics, varietal preferences, and economic thresholds.