Investigation of biodegradable insecticidal properties of different plant lectins on Tropinota (Epicometis) hirta (Poda, 1761) (Coleoptera: Cetoniidae)

Tropinota (Epicometis) hirta (Poda, 1761) (Coleoptera: Cetoniidae), a polyphagous agricultural pest that causes significant economic damage to fruits, vegetables and cereals. Due to its presence during the same period as bees, chemical control methods are not recommended. This study aims to evaluate the effectiveness of plant lectins as bioinsecticides in comparison to synthetic insecticides. Adult insects were collected from various locations in İvrindi district of Balıkesir, Türkiye, between March 25 and June 6, 2024. The insects were fed in vivo with lectins from Wisteria floribunda (Willd.) DC. (Fabales: Fabaceae) (WF), Phaseolus vulgaris L. (Fabales: Fabaceae) (PV), Triticum vulgaris L. (Poales: Poaceae) (TV) and Phytolacca americana L. (Caryophyllales: Phytolaccaceae) (PA) at concentrations of 200, 250 and 300 mg/g for 7 days. The highest lethal effect among the applied lectin doses was detected at the PA300 dose. Upon examining the insect gut tissues, it was found that the TV300 lectin dose contained higher levels of oxidants compared to the synthetic insecticide. Additionally, the applied lectins exhibited inhibitory effects on the activity of various digestive enzyme in insects. Our findings suggest that lectins can be used as a biodegradable alternative to chemical insecticides for controlling T. hirta.