## 4 Discussion
armigera_ larvae, especially on higher concentrations, but a notable mortality rate was also recorded on lower ones. It is believed that the interaction with the insect host can be more powerful and manageable in cases of absence of previous long-term relationships [41]. The lack of past interaction boosts the efficiency of EPF as the insect hosts have not developed defensive mechanisms on the new pathogen [42]. The selection of locally adapted virulent strains in agroecosystems is the initial step in commercialization and large-scale application [43; 44; 45]. Additionally, indigenous strains of EPF have ecological compatibility with insect pests, positive effects on the local environment, lessened pesticide residues in food, reduced risk of significant impact on non-target organisms, and increased biodiversity in managed ecosystems [46; 47; 48]. The entomopathogenic effect of the _Fusarium_ species has been reported by investigators on certain insect species, such as the greenhouse whitefly, _Trialeurodes vaporarium_ ([PERSON]) (Homoptera: Aleyrodidae) [49], the spruce budworm, _Choristoneura funifera_ ([PERSON].) (Lepidoptera: Tortricidae) [50], the wheat stem sawfly, _Ceplus cinctus_ ([PERSON]) (Hymenoptera: Cephidae) [51] and eggs and larvae of the tobacco cutworm, _Spodoptera litura_ ([PERSON]) (Lepidoptera: Nocutiidae) [52]. As reviewed by [PERSON] et al. [53], the most frequently reported entomopathogenic _Fusarium_ species lay between four species complexes of _Fusarium incarnatum-equistiel_, _F. fujikuroi_, _F. solani_, and _F. oxysporum. F. solani_ and _F. fujikuroi_ (homotypic synonym: _Gibberell fujikuroi_) showed a high mortality rate on the larvae of _H. armigera_ and once again confirmed the existing literature claiming the entomopathogenic traits of these species as they have been tested on a variety of insects [51]. Our results include the first ever report on the entomogenity of _F. chlamdogorum_. _ex dichamydogorum_, _F. pseudantlubilium_, _F. tonkinense_ (Bugnic.) (basionym: _Cylindrocarbon tonkinense_) and _F. algeriense_ as they induced mortality at 77%, 71%, 71%, and 61%, respectively, at high conidial concentrations. Lastly, there is substantial evidence of the _F. incarnatum-equistiel_ species complex being effective against insects and our results identified that one member of the complex, _F. longifundum_, induced 67% mortality on _H. armigera_ larvae. It is well known how this fungus, as a plant pathogen, can attack and kill its host plant. Some explanation of the entomopathogenic effect of the fungus was based on the production of toxins, such as beauvericin [54], fusarin C [55; 56], and moniliformin [57; 58]. Some strains of _Fusarium awenaceum_ (Fr.) Sacc. (Hypocreales: Nectriaceae) can synthesize enniantic cyclic peptides, primarily ennatiins A, B and B1 under laboratory conditions [54], but these enniants may have a role in plant pathogenicity [59]. The effectiveness against _H. armigera_ is of an importance as it is characterized by its resistance to many chemical insecticides [60; 61]. _F. solani_ appeared to be the most lethal against _H. armigera_ larvae, even though there have been some reports on the species' mutualistic relationship with insects. The lethal effect observed by [PERSON] et al. [62] reported that _Fusarium proliferation_ (Matsush.) Nirenberg (Hypocreales: Nectriaceae) isolates cannot produce significant amounts of toxic metabolites, which could be attributed to extracellular enzymes (e.g., proteases and chitinases). In fact, the capacity to synthesize enzymes involved in the degradation of the cuticle of insects has been demonstrated for some entomopathogenic fungi [63]. [PERSON] et al. [64] reported the production of chitinase and protease by hyphomycetes. So, treatment with formulations of _Fusarium_ induce the appearance of brown-black deposits of melanin on the integument of treated nymphs [62]. The same symptoms mentioned above were observed on the treated _H. armigera_ larvae with _Fusariumisolates.