Developmental effects of biopolymeric nanoparticles on Chrysodeixis includens (Walker)

Previous research has indicated that biopolymeric nanoparticles made of zein, the primary protein found in maize, are efficacious in inducing mortality within Noctuidae. However, this research was focused on the acute response. Because nanoparticles are more chemically reactive than their bulk counterparts, chronic non-lethal studies on pests are necessary prior to use in an integrated pest management program. To assess chronic exposure to zein nanoparticles (ZNP), we conducted life table studies on Chrysodexis includens (Walker) using a diet incorporated bioassay. Cohorts reared on non-lethal concentrations of empty zein nanoparticles (0.344 PPM) were compared to an untreated check (UTC). Individual larvae were checked daily for mortality and staged using head capsule slippage until pupation. Pupae were then sexed and weighed and then placed into containers as mated pairs. Egg deposition of adult females and larval eclosion were checked every two days. Results from the lifetable assays showed that there were no differences in pupal weights or eclosion rates. However, differences were noted in egg deposition per individual female (UTC: 117 ± 16, ZNP: 155 ± 6). Cohorts reared on zein nanoparticles had a higher net reproductive rate (1410.64 ± 142.40) than the untreated check (680.36 ± 271.22). These data suggest that zein nanoparticles may improve reproductive fitness of C. includens when administered in non-lethal concentrations over an individual’s lifetime. Further studies will address generational effects.