Effects of Lethal Bronzing Disease, Palm Height, and Temperature on Abundance and Monitoring of Haplaxius crudus

Abstract

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 H. crudus 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 H. crudus abundance. When the palms were infected with LB, at low temperature, H. crudus was more abundant on shorter than taller palms; however, H. crudus was more abundant on taller than shorter palms at the median and higher temperatures. These results may indicate that H. crudus 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.

DNA degradation in Haplaxius crudus (Hemiptera: Cixiidae) and Diaphorina citri (Hemiptera: Liviidae) on yellow sticky traps in Florida

“…P. aculeata’ ( Howard et al 1983 ). Unlike other insects, H. crudus appears to display a preference for phytoplasma-infected palms compared to healthy palms in field settings ( Mou et al 2020b ). Haplaxius crudus collected from population surveys in Mexico and Florida tested positive for ‘ Ca.…”

Identification of Green-Leaf Volatiles Released from Cabbage Palms (Sabal palmetto) Infected with the Lethal Bronzing Phytoplasma

“…Recently, the vector of LB was identified as the planthopper Haplaxius crudus (Hemiptera: Cixiidae) [3], which is a very widespread and abundant species in Florida and the Caribbean basin (including Mesoamerica and northern South America) [4]. During survey work in Florida in areas with active disease spread, it was demonstrated that populations of H. crudus were higher in areas of LB incidence and appeared to preferentially feed on LB-infected palms over healthy individuals [5]. Furthermore, the difference between LB-infected and healthy trees was demonstrated using a low-cost electronic nose (eNose) [6].…”