Bioactivity of Carlina acaulis Essential Oil and Its Main Component towards the Olive Fruit Fly, Bactrocera oleae: Ingestion Toxicity, Electrophysiological and Behavioral Insights

Among botanical insecticides based on essential oils (EOs) or their main components, Carlina acaulis EO and the aromatic polyacetylene carlina oxide, constituting more than 90% of its EO, were recently proven to be effective against the larvae and adults of some insect vectors and pests. In this study, the toxicity of C. acaulis EO and carlina oxide were tested on Bactrocera oleae adults using a protein bait formulation. The LC50 values of the C. acaulis EO and carlina oxide were 706 ppm and 1052 ppm, respectively. Electroantennographic (EAG) tests on B. oleae adults showed that both carlina EO and oxide elicited EAG dose-dependent responses in male and female antennae. The responses to the EO were significantly higher than those to carlina oxide, indicating that other compounds, despite their lower concentrations, can play a relevant role. Moreover, Y-tube assays carried out to assess the potential attractiveness or repellency of carlina oxide LC90 to B. oleae adults showed that it was unattractive to both males and females of B. oleae, and the time spent by both sexes in either the control or the treatment arm did not differ significantly. Overall, this study points out the potential use of C. acaulis EO and carlina oxide for the development of green and effective “lure-and-kill” tools.

Survey and Monitoring of Chinese Citrus Fly (Bactrocera minax Enderlein) in Sweet Orange Orchards of Sindhuli, Nepal

Chinese citrus fly, Bactrocera minax (Enderlein), is one of the most important pests of citrus. The pest is more problematic in the eastern part of the country, Nepal. Because of the difficulties associated with the control of this pest by chemical insecticides, farmers had experienced great losses in Sweet Orange. Therefore, a participatory field survey was conducted under farmer field conditions to assess losses and measure the efficacy of different local and recommended management options to address the problem of this pest. Study consisted of two major parts: monitoring of pest population and farmer’s survey. For monitoring three orchards were selected located at different altitude i.e. 1200 masl, 1300 masl and 1400 masl. Great Fruit fly Bait (25% protein hydrolysate and 0.1% abamectin) in McPhail traps were used for monitoring. Monitoring was done in every 7 days interval and lures were changed in every 15 days for the effectiveness. Only 18.3% farmers were using protein bait for the management of fruit fly. B. minax had peak population intensity at May and was found decreasing after June so the management practices should be adopted before June to prevent the loss by fruit fly. However, for best effective control attention for monitoring and management procedures has to take place throughout the life cycle of the insect.

Affinity capture of polyribosomes followed by RNAseq (ACAPseq), a discovery platform for protein-protein interactions

Defining protein-protein interactions (PPIs) is central to the biological sciences. Here, we present a novel platform - Affinity Capture of Polyribosomes followed by RNA sequencing (ACAPseq) - for identifying PPIs. ACAPseq harnesses the power of massively parallel RNA sequencing (RNAseq) to quantify the enrichment of polyribosomes based on the affinity of their associated nascent polypeptides for an immobilized protein ‘bait’. This method was developed and tested using neonatal mouse brain polyribosomes and a variety of extracellular domains as baits. Of 92 baits tested, 25 identified one or more binding partners that appear to be biologically relevant; additional candidate partners remain to be validated. ACAPseq can detect binding to targets that are present at less than 1 part in 100,000 in the starting polyribosome preparation. One of the observed PPIs was analyzed in detail, revealing the mode of homophilic binding for Protocadherin-9 (PCDH9), a non-clustered Protocadherin family member.