Translator Disclaimer
19 January 2022 Spatial Distribution of Lepidopteran Stem Borers in Louisiana Rice Fields
Megan M. Mulcahy, Blake E. Wilson, Thomas E. Reagan
Author Affiliations +

Louisiana rice is attacked by a complex of lepidopteran stem borers that injure the vegetative and reproductive stages of rice, reducing tillering and grain output. Currently, insecticidal seed treatments are used in Louisiana as a preemptive means to control stem borers in rice. Our objective was to better understand the spatial distribution of stem borers in Louisiana rice fields. Thirteen nontreated commercial rice fields in Louisiana were mapped using GPS software and surveyed for stem borer damage in 2017 and 2018. Damage was recorded by counting the number of blank panicles (whiteheads) within quadrats located at different areas in each field. An ANOVA, spatial interpolation, hotspot analysis, and negative binomial regression were used to determine where stem borer injury was concentrated and whether the distribution of these pests was influenced by rice stand count, field composition, and site location. The results show that stem borers are typically aggregated along field edges, with population density decreasing toward the center of rice fields. Stem borer damage was 4.2- and 3.9-fold greater along field edges than in field centers in 2017 and 2018, respectively. Hotspot spatial analysis revealed 41.7 and 52.1% of low-density clusters occurred at or near field centers, respectively. Negative binomial regression revealed stem borer injury declines with increasing distance from field edges, with regional differences in infestation levels. This suggests stem borer control efforts could be spatially targeted to improve the efficiency of pest management.

© The Author(s) 2022. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail:
Megan M. Mulcahy, Blake E. Wilson, and Thomas E. Reagan "Spatial Distribution of Lepidopteran Stem Borers in Louisiana Rice Fields," Environmental Entomology 51(2), 405-412, (19 January 2022).
Received: 9 August 2021; Accepted: 8 November 2021; Published: 19 January 2022

This article is only available to subscribers.
It is not available for individual sale.

Eoreuma loftini
insecticidal seed treatment
population distribution
spatial interpolation
Get copyright permission
Back to Top