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Entomopathogenic nematodes (EPNs) are an important component of integrated pest management (IPM) strategies; understanding their compatibility with other biocontrol options is of crucial importance in promoting their use. In this study, the toxicity of azadirachtin, sulfoxaflor, spindle oil (Mineral oil), and thyme oil was tested on the survival and pathogenicity of Steinernema carpocapsae (Weiser, 1955) (Rhabditida: Steinernematidae), Steinernema bicornutum sp. n. (Rhabditida: Steinernematidae), Heterorhabditis bacteriophora (Poinar, 1976) (Rhabditida: Heterorhabditidae), and Heterorhabditis indica (Poinar, Karunakar & David, 1992) under controlled conditions (25 ± 1 °C, 60 ± 10% RH). The toxicity of aforementioned agrochemicals to EPNs was evaluated in 12-well plates and the infective juveniles (IJs) of each EPN species (6000 IJs/50 µL ddh2O) were exposed to the recommended field concentrations of agrochemicals. In the pathogenicity tests, the agrochemical and IJs solutions (3000 IJs/ml agrochemical) were applied to potato tubers in plastic containers which contained 20 adults of Planococcus citri (Risso, 1813) (Hemiptera: Pseudococcidae). The survival of IJs and P. citri (Adults) was evaluated daily for three consecutive days after treatment. The results revealed that all tested EPN species were quite compatible with tested agrochemicals and showed survival of over 95% after 72 h of exposure to tested agrochemicals. EPNs and spindle oil combination induced the highest mortality of adult P. citri, and all EPN species caused mortalities over 90% at 72 h after treatment, except for S. bicornotum-spindle oil combination. Additive effects were observed in all combinations of EPNs with agrochemicals except for thyme oil. It appears, therefore, that EPNs applied in combination with azadirachtin, sulfoxaflor, and spindle oil have a great potential for successful control of P. citri. However, further studies are still required to determine the antagonistic or otherwise synergistic effects of tested chemicals on EPNs in controlling P. citri under field conditions. [ABSTRACT FROM AUTHOR]

One invasive species that decreases citrus fruit yield is the Asian citrus psyllid, Diaphorina citri Kuwayama. The psyllids are the carriers of Candidatus Liberibacter species, the pathogen that causes citrus greening disease (commonly called huanglongbing, or HLB), which is the most devastating citrus disease in the world. Originally from Southeast Asia, the Asian citrus psyllid, a highly invasive species, is spreading rapidly throughout the world. Regarding geographical distribution and population growth, climate change will aggravate its impacts on many citrus agroecosystems. However, limited information on the mechanisms underpinning the pest's invasion impedes the formulation of biosecurity risk measures. We highlight the potential suitable areas for D. citri, combining their climatic requirements, temperature and humidity, in the CLIMEX model. The model's performance was high, and it can be utilized for biosecurity risk assessment, as only 2.82% of the 496 known occurrence spots were located in areas deemed unsuitable by the model's fit. The potential habitat suitability for D. citri covered all continents except Antarctica, and the suitability ranges from unsuitable (EI < 0) to highly suitable areas (EI ≥ 30). Our model predicted suitable areas outside its known native and invaded regions, especially in Africa, South America, and Oceania. Most of these regions will remain suitable for D. citri in the future. This underscores the importance of our findings as a significant guide for future early detection and the development of climate-smart management strategies against D. citri. [ABSTRACT FROM AUTHOR]