A plant-free push–pull system using sustained-release electrospun micro-/nanofibers for insect behavioral manipulation
摘要
Plant-derived semiochemicals underpin the push–pull strategy, yet their widespread agricultural adoption is limited by the land requirements, growth dependence and inconsistent field performance of companion plants. Here we develop a fully plant-free push–pull system for managing the white grub Holotrichia parallela in peanut agroecosystems, achieved by embedding optimized PVOC blends into biodegradable electrospun fibers composed of an 8% PHB/2% PCL polymer matrix (PHB8/PCL2). The attractant mixture (1-heptanol and (Z)-3-hexenyl acetate) and repellent mixture (1,8-cineole and 2-ethylhexanol) were efficiently encapsulated (45–53%) within uniform fibers (1.24 ± 0.03 μm), which released volatiles following first-order kinetics for more than 56 days. Electroantennography confirmed sustained antennal detectability, with > 60% of initial response retained at day 14 and measurable activity through day 42. Behavioral assays showed that attractant-loaded fibers elicited ~ 65% attraction and maintained > 50% activity for 35 days, while repellent-loaded fibers induced 53–66% deterrence over the same period. In field trials conducted in peanut fields, the plant-free system reduced grub density by 73%, matching the efficacy of plant-based push–pull plots while outperforming commercial dispensers. The PHB8/PCL2 matrices degraded by > 50% within 60 days, avoiding environmental persistence. These results establish electrospun biodegradable fibers as a scalable semiochemical platform and a viable plant-free alternative for sustainable behavioral pest manipulation.