## 4 Discussion  
In this work, an endophytic yeast with antifungal effect against _B. cinerea_ isolated from _E. chiloensis_ was identified as _Naganishia_ sp. This is the first report of this fungal species as an endophyte from _E. chiloensis_. In previous studies, endophytic fungi (_Aureobasidium_ sp., _Epicoccum_ sp., and one species of the order Pleosporales) with antifungal activity against _B. cinerea_ were isolated from this plant species [12; 14]. _Naganishia_ sp. has been previously reported as endophytic fungus [16; 33; 34]. _Naganishia liquefaciens_ was found as endophyte in _Arnebia euchroma_, a medicinal plant found in the Himalayas [16]. _Naganishia albida_ and _Naganishia globosa_ were reported as endophytes in agricultural crops in 36 countries [33]. _Naganishia_ sp. was also isolated as endophyte from endemic xerophytic plants growing in an extremely arid desert in northwest China [34]. This study demonstrated that the endophytic yeast, _Naganishia_ sp., inhibited _B. cinerea_ growth by emitting VOCs. It has been previously described that VOCs emitted by microorganisms such as _Diaporte apicultatum_, _Aureobasidium__pullulans_, _Streptomyces__globisporus_, _Candidas__sp., and _Scharomoves_ sp. inhibit sporulation, spore germination, and mycelian growth of _B. cinerea_, modulating its pathogenicity [35; 36]. The mode of action of VOCs on _B. cinerea_ is not yet well understood. This study showed that VOCs emitted by the isolate _Naganishia_ sp. induced the production of a low number of conidiophores without conidia, affecting the sporulation of _B. cinerea_. Additionally, in this study was also shown that VOCs caused damage to the cell wall and plasma membrane of _B. cinerea_. It has been described that VOCs can penetrate cell membranes due to their hydrophobicity, generating changes in membrane potential and permeability, altering hypha integrity [36; 37]. Similar to these results, [PERSON] et al. [25] demonstrated that VOCs, emitted by _A. pullulans_, caused deformation in spores and germ tubes of _B. cinerea_ and _Alternaria__alternata__, leading to the release of cell contents and suggesting an alteration of the plasma membrane. Moreover, VOCs emitted by _Naganishia_ sp. promoted the accumulation of reactive oxygen species in _B. cinerea_, generating oxidative stress and lipoperoxidation. Oxidative stress could damage the plasma membrane and induce IC formation. Interestingly, conidiation in _B. cinerea_ is regulated by signaling pathways involved in cell differentiation, which can be inhibited by ROS, showing phenotypes with sporulation defects [38; 39]. In _B. cinerea_, the Nox complex (BcNoxA/B,  
Figure 12: Effect of VOCs emitted by _Naganishia_ sp. on _B. cinerea_ growth in vivo. (**A**) Infection area on tomato after 4 days post inoculation with _B. cinerea_. (**B**) Infection area on grape after 2 days post inoculation with _B. cinerea_. Bars represent the mean of three biological replicates \(\pm\) SD. For statistical analysis, Student’s \(t\)-test was performed. Columns with different letters are significantly different (\(p<0.05\)). BcNoxC) participates in mycelial growth, conidial development, and IC formation [40; 41]. VOCs, such as methyl thujate, induce the expression of Nox genes in _B. cinerea_, increasing ROS production and decreasing fungal pathogenicity [42]. Furthermore, in _A. alternata_, inactivation of the NoxA, NoxB, or NoxR genes reduces conidial by 95% [43]. Similar results were observed in _Coniothyrrium minitans_, where the Nox1 protein was essential for fungal condiation [44]. Therefore, based on this, it can be hypothesized that the increase in ROS produced by the VOCs emitted by endophytic yeast, _Naganishia_ sp., could produce a decrease in the formation of conidia in _B. cinerea_. On the other hand, some microbial VOCs cause cell death in fungi [45]; VOCs produced by the endophytic fungus _Sarocaladium brachiariae_ caused cell death in _Fusarium oxysporum_[46].