Feeding Activity, Salivary Amylase Activity, and Superficial Damage to Soybean Seed by Adult Edessa meditabunda (F.) and Euschistus heros (F.) (Hemiptera: Pentatomidae)

Abstract

Greenhouse and laboratory studies were conducted to evaluate feeding activity and superficial damage to soybean seed by the brown-winged stink bug, Edessa meditabunda (F.), and the Neotropical brown stink bug, Euschistus heros (F.). Soybean plants (cv. BRS 282), at R6 stage of development were used. Thirty pairs of each species were used individually for 48 h. Two daily observations (9:00 AM and 3:00 PM) were taken to record the number of bugs (feeding/resting) on plant parts. Harvested seeds imbibed in tetrazolium solution were photographed for measurement of the damaged surface. Adult E. meditabunda significantly preferred soybean stems (19.7 bugs) to pods (2.7). Feeding/resting was similar at 9:00 AM (mean number of 28.0 bugs) and 3:00 PM (24.3). Euschistus heros equally fed/stayed on stems (7.3 bugs) and pods (6.9), although most bugs (12.3) remained on the cage net; feeding/resting on all plant structures amounted to 13.7 bugs at 9:00 AM and 17.7 bugs at 3:00 PM. Amylase activity was greater for E. heros (41.61 ± 0.89 U/mg) and almost none for E. meditabunda (2.35 ± 0.14 U/mg). The superficial damage to seeds was significantly greater for E. meditabunda (22. 9 mm(2)) compared to E. heros (12.5 mm(2)). However, E. meditabunda caused less shrinkage of the seed tegument, while E. heros damage was deeper and seeds showed reduction in size.

Distinct properties of proteases and nucleases in the gut, salivary gland and saliva of southern green stink bug, Nezara viridula

“…Saliva is released into plant tissues resulting in enzymatic degradation of plant cell components (sugars and lipids), proteins and nucleic acids, and the liquefied digestion products are sucked back for further digestion in the gut78. While release of stink bug saliva and digestive enzymes into the plant to facilitate nutrient extraction is a primary cause of stink bug-associated crop damage910, the biochemical properties of these enzymes are unknown. Insights into stink bug digestive physiology will allow for development of enzymatically stable agents for stink bug control.…”

Stink Bugs (Pentatomidae)

“…Rizzo ( 1971 ) presented detailed information on the biology, immature stages, fi eld ecology, and host plants of Edessa meditabunda . This species has been the subject of studies regarding its association with and damaging potential to soy-bean (Silva et al 2012 ) and sunfl ower (Malaguido and Panizzi 1998b ) and nymph development and feeding behavior (Panizzi and Machado-Neto 1992 ); also, the behavior of newly hatched nymphs on the corions has been recently studied in detail (Calizotti and Panizzi 2014 ). Rizzo and Saini ( 1987 ) presented biology data on Edessa rufomarginata .…”

Ultrastructural analysis of salivary glands in a phytophagous stink bug revealed the presence of unexpected muscles

“…This lack of knowledge is intriguing as phytosuccivorous stink bugs are key crop pests, damaging seeds and developing fruiting structures [4,14,15]. In particular, the production of soybeans, Glycine max , in the neotropics is threatened by a complex of stink bugs that occur throughout most of the cultivation area, with the Neotropical brown stink bug, Euschistus heros (F.), being the most abundant pest [4,14,16,17].…”

“…heros directly damage seed tissues, making them pinched and wrinkled, and reducing the seed oil content and the germination rate, which consequently affects grain yield and quality [14,15,18]. Furthermore, the feeding punctures caused by stinkbugs facilitate contamination by plant pathogens and may even cause physiological disturbances, such as foliar retention and delayed seed maturation [4,19,20].…”