title: Relationship Between Piercing-Sucking Insect Control and Internal Lint and Seed Rot in Southeastern Cotton (Gossypium hirsutum L.).
abstract: In 1999, crop consultants scouting for stink bugs (Hemiptera spp.) in South Carolina discovered a formerly unobserved seed rot of cotton that caused yield losses ranging from 10 to 15% in certain fields. The disease has subsequently been reported in fields throughout the southeastern Cotton Belt. Externally, diseased bolls appeared undamaged; internally, green fruit contain pink to dark brown, damp, deformed lint, and necrotic seeds. In greenhouse experiments, we demonstrated transmission of the opportunistic bacterium Pantoea agglomerans by the southern green stink bug, Nezara viridula (L.). Here, green bolls were sampled from stink bug management plots (insecticide protected or nontreated) from four South Atlantic coast states (North Carolina, South Carolina, Georgia, and Florida) to determine disease incidence in the field and its association with piercing-sucking insects feeding. A logistic regression analysis of the boll damage data revealed that disease was 24 times more likely to occur (P = 0.004) in bolls collected from plots in Florida, where evidence of pest pressure was highest, than in bolls harvested in NC with the lowest detected insect pressure. Fruit from plots treated with insecticide, a treatment which reduced transmission agent numbers, were 4 times less likely to be diseased than bolls from unprotected sites (P = 0.002). Overall, punctured bolls were 125 times more likely to also have disease symptoms than nonpunctured bolls, irrespective of whether or not plots were protected with insecticides (P = 0.0001). Much of the damage to cotton bolls that is commonly attributed to stink bug feeding is likely the resulting effect of vectored pathogens.
authors.affiliation: U.S. Department of Agriculture, Agricultural Research Service, Southern Plains Agricultural Research Center, Cotton Pathology Research Unit, 2765 F&B Rd., College Station, TX 77845. Gino.Medrano@ars.usda.gov.
authors.forename: Enrique G
authors.initials: EG
authors.lastname: Medrano
authors.affiliation: U.S. Department of Agriculture, Agricultural Research Service, Southern Plains Agricultural Research Center, Cotton Pathology Research Unit, 2765 F&B Rd., College Station, TX 77845.
authors.forename: Alois A
authors.initials: AA
authors.lastname: Bell
authors.affiliation: Clemson University, Department of Entomology, Blackville, SC 29817.
authors.forename: Jeremy K
authors.initials: JK
authors.lastname: Greene
authors.affiliation: University of Georgia, Department of Entomology, Tifton, GA 31793.
authors.forename: Phillip M
authors.initials: PM
authors.lastname: Roberts
authors.affiliation: North Carolina State University, Department of Entomology, Raleigh, NC 27695.
authors.forename: Jack S
authors.initials: JS
authors.lastname: Bacheler
authors.affiliation: University of Florida, NFREC, Department of Plant Pathology, Quincy, FL 32351.
authors.forename: James J
authors.initials: JJ
authors.lastname: Marois
authors.affiliation: University of Florida, NFREC, Department of Plant Pathology, Quincy, FL 32351.
authors.forename: David L
authors.initials: DL
authors.lastname: Wright
authors.affiliation: U.S. Department of Agriculture, Agricultural Research Service, Southern Plains Agricultural Research Center, Cotton Pathology Research Unit, 2765 F&B Rd., College Station, TX 77845.
authors.forename: Jesus F
authors.initials: JF
authors.lastname: Esquivel
authors.affiliation: Cotton Incorporated, Cary, NC 27513.
authors.forename: Robert L
authors.initials: RL
authors.lastname: Nichols
authors.affiliation: USDA, ARS, SPARC, 2765 F&B Rd., College Station, TX 77845.
authors.forename: Sara
authors.initials: S
authors.lastname: Duke
mesh_terms: D000818:Animals; D005638:Fruit / Q000382:microbiology; D003368:Gossypium; D060434:Herbivory; D020062:Heteroptera / Q000502:physiology*; D007300:Insect Control; D007303:Insect Vectors / Q000382:microbiology*; D008954:Models, Biological; D020636:Pantoea / Q000502:physiology*; D010935:Plant Diseases / Q000382:microbiology*; D012639:Seeds / Q000382:microbiology; D015144:Southeastern United States
keywords: disease; pesticide; vector