Fusarium genus is a wide host phytopathogen causing significant losses in multiple crops, including hops. There is limited information on the sustainable management of Fusarium spp. in hop fields. Trichoderma is an endophytic fungus used in agriculture as a biological control agent (BCA) and as a plant growth promoter. It has been used to antagonize Fusarium spp. in other crops. The objective of the current study was to identify indigenous hop field Trichoderma isolates with biocontrol and hop growth promotion capabilities. Three isolates of Fusarium and eleven autochthonous Trichoderma isolates collected from sustainable hop fields were evaluated in this work. Direct confrontation tests (the physical interaction between the pathogen and BCA and their competition for space and nutrient resources) and membrane tests (the capacity of the BCA to produce metabolites or enzymes through a cellophane film and inhibit the development of the pathogen) assessed the antagonism of these Trichoderma isolates against Fusarium culmorum, F. sambucinum, and F. oxysporum. A bioassay with hop plantlets inoculated with a spore suspension of Trichoderma was performed to assess its hop growth enhancement. T. hamatum (T311 and T324), T. virens T312, and T. gamsii T327 showed high growth inhibition of Fusarium spp. phytopathogens and high plant growth promotion. Native Trichoderma isolates from sustainable hop-producing soils have great potential as BCAs and hop growth promoters.

Acanthoscelides obtectus, one of the world’s most important post-harvest pests, attacks wild and cultivated common beans (Phaseolus vulgaris L.). Four Trichoderma strains, Trichoderma arundinaceum IBT 40837 (=Ta37), a wild-type strain producer of trichothecene harzianum A (HA); two transformed strains of Ta37, Ta37-17.139 (Δtri17) and Ta37-23.74 (Δtri23); and T. brevicompactum IBT 40841 (=Tb41), a wild-type strain producer of the trichothecene trichodermin, were evaluated to determine the effect of these compounds on the virulence of A. obtectus and the effect of these strains on the seed’s capacity of germination and on the agronomic traits of the plants grown from these seeds. Treatments of bean seeds with different Trichoderma strains provided varying survival rates in A. obtectus adults, so life survival of insects after Tb41 strain application was reduced to 15 days. Δtri17 and Tb41 strains sprayed on P. vulgaris beans resulted in low weight losses (1.21 and 1.55%, respectively). In spite of the low germination percentage of beans treated with Δtri23 strain (lower than the germination percentages of the rest of the fungal strains applied), this treatment encouraged a greater Wet Weight of Aerial Part of the plants grown from both damaged and undamaged beans. High germination rates of Ta37 and Δtri17 strains (higher than with the rest of treatments), did not turn into a greater Wet Weight Aerial Part and Wet Weight of Root System in the future plants developed. Linear regression between the number of exit holes and the wet weight aerial part on the one hand, and between the number of exit holes and the wet weight root system on the other, showed interaction, so Δtri23 and Tb41 strains behaved differently in comparison to their respective control treatments. The number of exit holes of beans treated with Δtri23 or Tb41 was negatively correlated with both the wet weight aerial part and the wet weight root system in P. vulgaris plants. Δtri23 sprayed on undamaged beans caused the greatest Wet Weight Aerial Part and wet weight root system in plants. Due to the good results obtained by Δtri23 and Tb41 strains in this work, more studies for A. obtectus control, P. vulgaris plant growth and trichothecenes production by these strains should be explored, in order to advance in the knowledge of how these fungi could be used in the field crop, together with the application of management strategies to mitigate risks for farmers and to minimize environmental contamination.