Sequential Isolation of Essential Oils Repellent to the Red Palm Weevil Rhynchophorus ferrugineus Olivier (Coleoptera: Curculionidae).

The push-pull approach using semiochemicals in pest control requires both an attractant and a repellent. Many previous studies have arbitrarily tested one or more known insect repellents or plant essential oils (EOs) hoping to find repellents of an insect pest. We used a comprehensive approach that synergistically tests in the field numerous natural volatiles from commercial EOs to identify repellents of the red palm weevil Rhynchophorus ferrugineus (Coleoptera: Curculionidae), a worldwide pest of palms and date palms.

Absolute Configuration of the Spherical Mealybug Sex Pheromone, γ-Necrodyl Isobutyrate: Chemoenzymatic Synthesis and Bioassays.

The spherical mealybug, (Hemiptera: Pseudococcidae), is a major global pest causing feeding damage to leaves and fruits of citrus varieties, soybean, mango, pomegranate, and grapevines. Females of the mealybug release a sex pheromone that was identified recently as a mixture of γ-necrodyl isobutyrate and γ-necrodol. The identification required synthesis based on a natural source of -α-necrodol, of unknown chirality, obtained from essential oil of Spanish lavender, .

Development of an immunoassay and a sol-gel-based immunoaffinity cleanup method for coplanar polychlorinated biphenyls from soil and sediment samples.

Two polychlorinated biphenyls (PCB) enzyme linked immunosorbent assays (ELISAs) were developed using goat PCB purified immunoglobulin (IgG) antibodies (Abs). The IgGs exhibited the highest affinity toward PCB-77 (24 ng mL(-1)) with sensitivities in the range of 6-11 ng mL(-1). The Abs cross-reacted with PCB-126 and the heptachlorodibenzofuran 1,2,3,4,6,7,8-HpCDF but not with PCB-169, PCB-118, Aroclor 1232, 1248, 1260 or the hexachlorodibenzofuran 2,3,4,6,7,8-HxCDF.

Bioavailability of backbone cyclic PK/PBAN neuropeptide antagonists--inhibition of sex pheromone biosynthesis elicited by the natural mechanism in Heliothis peltigera females.

The bioavailability (i.e. ability to penetrate the insect cuticle, to reach the target organ and to exert bioactivity) of two backbone cyclic (BBC) pyrokinin/pheromone biosynthesis-activating neuropeptide (PK/PBAN) antagonistic peptides was tested by applying them topically to Heliothis peltigera females and monitoring the resulting inhibition of sex pheromone production elicited by the natural (endogenous) mechanism during scotophase.

A novel dihydroimidazoline, trans-Pro mimetic analog is a selective PK/PBAN agonist.

The pyrokinin/pheromone biosynthesis activating neuropeptide (PK/PBAN) family plays a significant role in the regulation of reproductive and developmental processes in a variety of insects. A transPro, type I beta-turn has been previously identified as important for the activity of PK/PBAN peptides. A PK/PBAN analog (PPK-Jo) incorporating a novel dihydroimidazole transPro mimetic motif was evaluated in four PK/PBAN bioassays (pheromonotropic, melanotropic, pupariation and hindgut myotropic).