First Record of Aspergillus fijiensis as an Entomopathogenic Fungus against Asian Citrus Psyllid, Diaphorina citri Kuwayama (Hemiptera: Liviidae).

The Asian citrus psyllid Kuwayama (Hemiptera: Liviidae) is the most widespread and devastating pest species in citrus orchards and is the natural vector of the phloem-limited bacterium that causes Huanglongbing (HLB) disease. Thus, reducing the population of is an important means to prevent the spread of HLB disease. Due to the long-term use of chemical control, biological control has become the most promising strategy. In this study, a novel highly pathogenic fungal strain was isolated from naturally infected cadavers of adult . The species was identified as using morphological identification and phylogenetic analysis and assigned the strain name GDIZM-1. Tests to detect aflatoxin B demonstrated that GDIZM-1 is a non-aflatoxin B producer. The pathogenicity of the strain against was determined under laboratory and greenhouse conditions. The results of the laboratory study indicated that nymphs from the 1st to 5th instar and adults of were infected by GDIZM-1. The mortality of nymphs and adults of caused by infection with increased with the concentration of the conidial suspension and exposure time, and the median lethal concentration (LC) and median lethal time (LT) values gradually decreased. The mortality of for all instars was higher than 70%, with high pathogenicity at the 7th day post treatment with 1 × 10 conidia/mL. The results of the greenhouse pathogenicity tests showed that the survival of adults was 3.33% on the 14th day post-treatment with 1 × 10 conidia/mL, which was significantly lower than that after treatment with the GDIZMMa-3 strain and sterile water. The results of the present study revealed that the isolate of GDIZM-1 was effective against and it provides a basis for the development of a new microbial pesticide against after validation of these results in the field.