<i>Trichoderma</i> spp. from Misiones, Argentina: effective fungi to promote plant growth of the regional crop <i>Ilex paraguariensis</i> St. Hil

Abstract

<i>Ilex paraguariensis</i> St. Hil (yerba mate) is an important crop in the north of Argentina, mainly in Misiones province. The application of <i>Trichoderma</i> as a biocontroller and biofertilizer can replace or reduce the use of agrochemicals, decreasing the negative ecological impact. In this research, we evaluated <i>in vitro</i> and <i>in vivo</i> antagonistic and plant growth promoting (PGP) properties of <i>Trichoderma</i> species isolated from different regions of Misiones province. Dual culture assays of <i>Trichoderma</i> against phytopathogenic fungi associated with yerba mate showed that <i>T. stilbohypoxyli</i> LBM 120 was the most effective antagonist, inhibiting in more than 75% all phytopathogen growth. <i>Trichoderma atroviride</i> LBM 112 and <i>T. stilbohypoxyli</i> LBM 120 were positive on endoglucanase, protease, chitinase, siderophore production, and phosphate solubilisation showed the best biological control agents and PGP properties. The PGP properties of <i>Trichoderma</i> spp. evaluated <i>in vivo</i> on yerba mate seedlings showed that <i>T. atroviride</i> LBM 112, <i>T. stilbohypoxyli</i> LBM 120, and <i>T. koningiopsis</i> LBM 219 enhanced plant dry weight over 47% in total and 24% in the aerial part. Moreover, <i>T. koningiopsis</i> LBM 219 increased root dry weight 25% in contrast with <i>in vitro</i> controls. In conclusion, native <i>Trichoderma</i> strains could be a sustainable solution to improve yerba mate yield.