Comparison of Predatory Performance among Three Ladybird Species, IHarmonia axyridis/I, ICoccinella septempunctata/I and IHippodamia variegata/I, Feeding on Goji Berry Psyllid, IBactericera gobica/I

The goji berry, Lycium barbarum L., is a prominent indigenous medicinal plant in Northern China. The high nutrient content of fruits may make goji berry plants susceptible to pests. The goji berry psyllid Bactericera gobica is an extensively prevalent and devastating pest. The current primary approaches employed for goji berry psyllid prevention involve the utilization of chemical pesticides, which may potentially pose risks to human health and the environment. The advantage of biological control, in contrast to alternative methods, lies in its provision of a cost-effective and sustainable control system with minimal adverse effects. By comparing the predatory performance of three ladybird species preying on psyllids, our study suggests that each species possesses distinct advantages as potential predators of psyllids. Further field studies are necessary to determine the most promising ladybird species for rapid impact through inundative biological control, considering the specific environmental adaptability of each ladybird species. This study is expected to provide evidence supporting the potential of promising ladybird species as an effective biological control agent against goji berry psyllids. The psyllid Bactericera gobica is a serious pest in goji berry orchards. The current primary psyllid control methods involve chemical pesticides, which pose potential risks to human health and the environment. The implementation and promotion of biological control agents should receive increased attention as an alternative approach to safeguarding goji berry orchards. To compare the predatory performance of three potential biocontrol agents of psyllids, including Harmonia axyridis, Coccinella septempunctata and Hippodamia variegata, the functional response and intraspecific interactions of adult ladybirds were studied under laboratory conditions. We observed a significantly higher searching efficiency (0.84 ± 0.09) in H. axyridis when preying on psyllids compared to H. variegata (0.55 ± 0.05), whereas the handling time for psyllids was considerably longer in H. axyridis (7.33 ± 0.83 min) than in H. variegata (5.67 ± 0.97 min). The impact of intraspecific interactions on H. variegata (0.44 ± 0.04) was significantly greater than that on C. septempunctata (0.29 ± 0.03), whereas the maximum consumption by C. septempunctata (223.35 ± 41.3) significantly exceeded that of H. variegata (133.4 ± 26.9). Our study suggests that each of these three ladybird species possesse