A competitive immunoassay for detecting triazophos based on fluorescent catalytic hairpin self-assembly.

A rapid detection method is introduced for residual trace levels of triazophos in water and agricultural products using an immunoassay based on catalytic hairpin self-assembly (CHA). The gold nanoparticle (AuNPs) surface was modified with triazophos antibody and sulfhydryl bio-barcode, and an immune competition reaction system was established between triazophos and its ovalbumin-hapten (OVA-hapten). The bio-barcode served as a catalyst to continuously induce the CHA reaction to achieve the dual signal amplification.

[Ecological functions of E-β-farnesene on aphids and their natural enemies in potato field.].

As a most common component of aphid alarm pheromone, E-β-farnesene (EβF) could not only dispel aphids, but also modify some behavioral responses of their natural enemies. In order to investigate the ecological function of EβF, its influence on the population dynamics of Myzus persicae (Sulzer), Aphis gossypii (Glover), Macrosiphum euphorbiaein (Thomas) and their natural enemies was studied in potato fields. The results showed that there were significantly lower aphid abundance (2012, 2013), higher ladybird beetle abundance (2012, 2013), and higher mummified aphid abundance (2012) on potato plants in EβF treated plots (100 μL per week).