Effects of Lethal Bronzing Disease, Palm Height, and Temperature on Abundance and Monitoring of <i>Haplaxius crudus</i>

• Main Authors: De-Fen Mou, Chih-Chung Lee, Philip G. Hahn, Noemi Soto, Alessandra R. Humphries, Ericka E. Helmick, Brian W. Bahder
• Format: Article
• Language: English
• Published: MDPI AG 2020-10-01
• Series: Insects
• Subjects: insect vector; phytoplasma; vector preference; interactive effects; Hemiptera; Cixiidae
• Online Access: https://www.mdpi.com/2075-4450/11/11/748

Insect vector feeding preference and behavior play important roles in pathogen transmission, especially for pathogens that solely rely on insect vector transmission. This study aims to examine the effects of the 16SrIV-D phytoplasma, the causal agent of lethal bronzing (LB) disease of palms, on associated auchenorrhynchan insects. The numbers of auchenorrhynchans collected during weekly surveys during a yearlong study using yellow sticky traps were analyzed. The cumulative number of <i>H. crudus</i> was 4.5 times greater on phytoplasma-infected relative to non-infected palms. Other auchenorrhynchans showed no difference between phytoplasma-infected and non-infected palms or were greater on non-infected rather than on infected palms. Furthermore, we examined the effects of LB, palm height, temperature, and the interactive effects of these factors on <i>H. crudus</i> abundance. When the palms were infected with LB, at low temperature, <i>H. crudus</i> was more abundant on shorter than taller palms; however, <i>H. crudus</i> was more abundant on taller than shorter palms at the median and higher temperatures. These results may indicate that <i>H. crudus</i> prefers LB-infected palms over non-infected palms. The interactive effects of LB, palm heights, and temperature further suggest that vector monitoring and disease management should be optimized according to seasonal variation in temperature.