## 4 Discussion
We observed that a small percentage of larvae died, without any significant difference between larvae fed with untreated and _B. bussiana_-treated maize plants. We did not observe fungal outgrowth from _S. frugiperda_ cadavers; therefore, the larvae probably were not in direct contact with _B. bussiana_ blastospores. It was not possible to determine the presence of _B. bussiana_ in the plant tissues that were used to feed the larvae since there was no plant material left after the larvae were fed. However, in our previous studies, we found _B. bussiana_ as an endophyte in _Zea mays_ plants that grew after _B. bussiana_-methylcellulose-seed treatments [26]. One perspective from this study is to analyze the microbiota of _S. frugiperda_ excrement to determine if _B. bussiana_ was present. On the other hand, we observed that _S. frugiperda_ larvae fed on plants treated with _B. bussiana_ strain PTG4 had their development considerably affected, with a prolonged larval stage, a decline in larval weight, and a smaller number of pupae. In addition, we observed a high number of escaped larvae that were fed on GHA _B. bussiana_ strain-treated plants (26.7%) (Table 1), and the remaining showed a decline in pupal length and weight. [PERSON] [39] reported that by adding cultured _B. bussiana_ to the insects' diet, after removing mycelia, it was possible to reduce the percentage of pupation and the pupation time was prolonged. On the other hand, [PERSON] et al. [40] reported that adult malformations occurred in _B. bussiana_-treated squash beetles. [PERSON] and [PERSON] [15] did not find any difference in cotton boll worm and pupal weight when the insects were fed on _B. bussiana_ and _Purpurecillium lilacinum_ inoculated cotton plants. In our bioassays, since they were no-choice experiments, there was not sufficient remaining plant material to analyze and determine if there were any feeding preferences of larvae between negative control plants and _B. bussiana_-treated plants. Another important observation of this study was the adult male/female ratio obtained after the development of larvae fed on _B. bussiana_-treated _Z. mays_ plants. We observed a lower number of adult male moths. Interestingly [PERSON] et al. recently reported differences in _S. frugiperda_ female fertility, fecundity, and longevity using corn plants endophystically-inoculated with _B. bussiana_ by foliar spray treatments [41]. In contrast, they did not find significant differences in the sex ratio of _Helicoverpa gelotopoecon_ when they were fed on _B. bussiana_ treated soybean plants [42]. [PERSON] et al. observed a higher number of emerged males in their study with different fungal strains to protect _Vicia faba_ and _Phaseolus vulgaris_ against _Lirionyza huidobensis_ [43]. In addition, we observed apparent parthenogenesis in female adults, but further studies are needed to determine the cause of this, in addition to the analyses of the longevity, survival capacity, eating habits, or any other changes in the life cycle of the larvae born from these eggs. Furthermore, [PERSON] et al. (2013) reported a reduced survival and fecundity of _Sitobion avenue_ after feeding on maize plants inoculated with _B. bussiana_. Insect immunity is influenced by successive exposures to the same pathogen and has a long-term effect on its survival ([PERSON] et al., 2014). More studies are needed to determine whether _B. bussiana_ affects _S. frugiperda_ successive generations. In this regard, [PERSON] et al. (2010) reported that endophytic _B. bussiana_ established after foliar treatment of _Citrus limon_ plants acted as a growth suppressor to three successive generations of _Diaphorina citri_. Based on our laboratory results, two preliminary field trials in 2019 were conducted. The main objective was to analyze the effect of GHA _B. bussiana_-seed treatment on natural _S. frugiperda_ populations, as we observed no mortality but some effects on the insect physiology and certain avoidance to the treated plants (Table 1).