Knowledge of specific peroxidases that respond to aphid herbivory is limited in C4 grasses, but could provide targets for improving defence against these pests. A sorghum (Sorghum bicolor (L.) Moench) peroxidase (SbPrx-1; Sobic.
View Article and Find Full Text PDFThe western chinch bug, Blissus occiduus Barber, is a serious pest of buffalograss, Buchloe dactyloides (Nuttall) due to physical and chemical damage caused during the feeding process. Although previous work has investigated the feeding behaviors of chinch bugs in the Blissus complex, no study to date has explored salivary gland morphology and the associated salivary complex of this insect. Whole and sectioned B.
View Article and Find Full Text PDFBackground: Seed treatment insecticides have become a popular management option for early-season insect control. This study investigated the total uptake and translocation of seed-applied [(14) C]imidacloprid, [(14) C]clothianidin and [(14) C]flupyradifurone into different plant parts in three soybean vegetative stages (VC, V1 and V2). The effects of soil moisture stress on insecticide uptake and translocation were also assessed among treatments.
View Article and Find Full Text PDFBackground: Neonicotinoid insecticides are widely known for their broad-spectrum control of arthropod pests. Recently, their effects on plant physiological mechanisms have been characterized as producing a stress shield, which is predicted to enhance tolerance to adverse conditions. Here we investigate the molecular underpinnings of the stress shield concept using the neonicotinoid thiamethoxam in two separate experiments that compare gene expression.
View Article and Find Full Text PDFOxidative enzymes are one of many key players in plant tolerance responses and defense signaling pathways. This study evaluated gene expression of four buffalograss transcripts (two peroxidases, a catalase, and a GRAS (gibberellic acid insensitive [GAI], repressor of GAI, and scarecrow) and total peroxidase activity in response to western chinch bug (Blissus occiduus Barber) feeding in susceptible and resistant buffalograsses (Buchloë dactyloides (Nuttall) Engelmann). Basal levels of all four transcripts were consistently higher in the resistant buffalograss when compared with the susceptible genotype, which suggests important physiological differences exist between the two buffalograsses.
View Article and Find Full Text PDFBackground: Neonicotinoid insecticides are generally efficacious against many turfgrass pests, including several important phloem-feeding insects. However, inconsistencies in control of western chinch bugs, Blissus occiduus, have been documented in field efficacy studies. This research investigated the efficacy of three neonicotinoid insecticides (clothianidin, imidacloprid and thiamethoxam) against B.
View Article and Find Full Text PDFImmature blow flies (Calliphoridae) are typically the first colonizers of cadavers. Identification of the early instars using traditional, morphology-based keys is difficult because of their small size, similarity, and simplicity in external morphology. Information derived from molecular genetic data would augment the accurate identification of immature flies.
View Article and Find Full Text PDFThe stable fly, Stomoxys calcitrans (L.), has been considered one of the most serious biting flies of confined and pastured livestock. The economic losses caused by the stable fly to the cattle industry in the United States exceed $2 billion annually.
View Article and Find Full Text PDFThe western chinch bug, Blissus occiduus Barber, has been documented as one of the most serious pests of buffalograss, Buchloë dactyloides (Nuttall) Engelmann, and zoysiagrass, Zoysia japonica Steudel, grown for turf in midwestern states. Resistance to the western chinch bug has been identified in both buffalograsses and zoysiagrasses. Choice and no-choice studies were conducted to determine the categories (antibiosis, antixenosis, and tolerance) of three resistant buffalograsses (PX3-5-1', 196', and 184') and three resistant zoysiagrasses (El Toro, Emerald, and Zorro).
View Article and Find Full Text PDFA 2-yr study was conducted to document the influence of selected buffalograss, Buchloë dactyloides (Nuttall) Engelmann, management practices (three mowing heights and five nitrogen levels) on the seasonal abundance of the western chinch bug, Blissus occiduus Barber (Heteroptera: Lygaeidae), and its beneficial arthropods. Vacuum, pitfall, and sticky traps samples were collected every 14 d from the middle of May through October from western chinch bug-resistant ('Prestige') and -susceptible ('378') buffalograss management plots. In total, 27,374 and 108,908 western chinch bugs were collected in vacuum and pitfall traps, respectively.
View Article and Find Full Text PDFWhen insect evidence is obtained during autopsy, forensic entomologists make decisions regarding the effects of low-temperature (-1 degrees C to 4 degrees C) storage of the body and associated insects when estimating the post-mortem interval (PMI). To determine the effects of storage in a morgue cooler on the temperature of maggot masses, temperatures inside and outside of body bags containing a human cadaver and porcine cadavers (seven replicates) were measured during storage. Temperatures remained significantly higher (p<0.
View Article and Find Full Text PDFThe impact of Blissus occiduus Barber feeding on resistant ('Prestige') and susceptible ('378') buffalograsses, Buchloë dactyloides (Nuttall) Engelmann, was evaluated through measurement of carbon exchange rate, light and carbon assimilation (A-C(i)) curves, chlorophyll a fluorescence, and nonstructural carbohydrates. No significant differences in carbon exchange rates were observed between infested and control plants for 378 at 5 and 10 d after infestation; however, at 20 d after chinch bug introduction, significant differences in carbon exchange rates between infested and control 378 plants were detected. Carbon exchange rates were similar between infested and control Prestige plants at 5,10, and 20 d after infestation, suggesting that resistant plants can allocate energy for recovery from chinch bug injury.
View Article and Find Full Text PDFChinch bugs are common pests of many agronomic and horticulturally important crops and turfgrasses. Previous research has indicated that some grasses exhibit resistance to multiple chinch bug species, whereas others are resistant to only one species. The objectives of this research were to document differences in the probing frequencies and locations among Blissus species as well as differences in mouthpart morphology as a first step in understanding the differential responses of grasses to chinch bug feeding.
View Article and Find Full Text PDFChinch bugs are common pests of many agronomic and horticulturally important crops and turfgrasses. The extensive overlap of plant hosts and geographic distribution of Blissus leucopterus leucopterus (Say), Blissus leucopterus hirtus Montandon, Blissus insularis Barber, and Blissus occiduus Barber underscores the importance of identifying resistant germplasm. Cool- and warm-season turfgrasses and sorghum, Sorghum bicolor (L.
View Article and Find Full Text PDFThe chinch bug, Blissus occiduus Barber (Hemiptera: Blissidae), is an important pest of buffalograss, Buchloë dactyloides (Nutall) Engelmann and potentially other turfgrass, crop, and non-crop hosts. Choice studies documented the number of B. occiduus present on selected turfgrasses, crops and weeds, and provided important insights into the host preferences of this chinch bug.
View Article and Find Full Text PDFThe sex pheromone of the scarab beetle, Phyllophaga anxia, is a blend of the methyl esters of two amino acids, L-valine and L-isoleucine. A field trapping study was conducted, deploying different blends of the two compounds at 59 locations in the United States and Canada. More than 57,000 males of 61 Phyllophaga species (Coleoptera: Scarabaeidae: Melolonthinae) were captured and identified.
View Article and Find Full Text PDFThis research investigated the role of oxidative enzymes in the defense response of buffalograss, Buchloë dactyloides (Nuttall) Engelmann, to Blissus occiduus Barber. Changes in catalase and peroxidase activity were observed in both resistant and susceptible buffalograsses in response to chinch bug feeding. Susceptible plants were shown to have a lower level of catalase activity compared with their respective control plants.
View Article and Find Full Text PDFBlissus occiduus Barber is an important pest of buffalograss, Buchloë dactyloides (Nuttall) Engelmann, turf. No-choice studies documented the susceptibility of selected turfgrasses, crops, and weeds to B. occiduus feeding.
View Article and Find Full Text PDFChoice and no-choice studies were conducted to determine the categories (antibiosis, antixenosis, and tolerance) of resistance of four buffalograsses (NE91-118, 'Bonnie Brae', 'Cody', and 'Tatanka') previously identified as resistant to the western chinch bug, Blissus occiduus Barber. Antibiosis studies found no significant differences in western chinch bug fecundity, nymphal development, or survival among the resistant and susceptible buffalograsses. Tolerance studies indicated that NE91-118, Cody, and Tatanka exhibited moderate-to-high levels of tolerance based on western chinch bug damage ratings and plant height, whereas Bonnie Brae exhibited moderate-to-low levels of tolerance.
View Article and Find Full Text PDFBlissus occiduus Barber has emerged as an important insect pest of buffalograss, Buchloë dactyloides (Nuttall) Engelmann, in Nebraska. This research evaluated selected buffalograss germplasm for resistance to B. occiduus.
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