Evaluation of Artemisia absinthium L. Essential Oil as a Potential Novel Prophylactic against the Asian Citrus Psyllid Diaphorina citri Kuwayama

Simple Summary The extensive use of synthetic chemical pesticides to manage insect pests has adversely affected humans and the environment. Therefore, botanical pesticides could be helpful as alternative tools for integrated pest management since they have low mammalian toxicity and minimal risk of developing resistance in target pests. Our current study aimed to evaluate the efficacy of Artemisia absinthium essential oil (AAEO) as a novel alternative to synthetic insecticides against Diaphorina citri. The results indicated that AAEO could be developed as a valuable novel crop protectant against D. citri. Interest in developing novel crop protectants has increased in the recent decade due to the harmful effects of synthetic pesticides on humans and the environment. Diaphorina citri threatens the citrus industry worldwide and is the primary vector of phloem-limited bacterium (HLB). However, there is no available cure for HLB. Diaphorina citri management mainly depends on the use of synthetic insecticides, but their massive application leads to resistance in pest populations. Therefore, alternative pest management strategies are needed. Our results indicated that fewer D. citri adults settled on plants treated with AAEO than on control 48 h after release. The psyllids fed on citrus leaves treated with AAEO significantly reduced the honeydew production compared to the control. The AAEO showed potent ovicidal activity against the D. citri eggs with LC50 5.88 mg/mL. Furthermore, we also explored the fitness of D. citri on AAEO-treated and untreated Citrus sinensis by using two-sex life table tools. Our results revealed that the intrinsic rate of increase (r) was higher on untreated seedlings (0.10 d(-1)) than those treated with an LC20 concentration of AAEO (0.07 d(-1)). Similarly, the net reproductive rate (R-0) was higher for untreated seedlings (14.21 offspring) than those treated (6.405 offspring). Furthermore, the AAEO were safer against Aphis mellifera, with LC50 35.05 mg/mL, which is relatively higher than the LC50 24.40 mg/mL values against D. citri. The results indicate that AAEO exhibits toxic and behavioral effects on D. citri, which can be a potential candidate for managing this pest.