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The species Trichoderma harzianum was analyzed as possible biocontrol agent of Alternaria alternata under different environmental conditions (water activity and temperature). The strains were analyzed macroscopically to obtain the Index of Dominance. The analysis was completed using two microscopic techniques. T. harzianum showed dominance on contact over A. alternata at all testing temperatures and water activities tested except at 0.95 a(w) and 15 degrees C, at which T. harzianum inhibited A. alternata at a distance. Biocontrol was governed by different mechanisms such as competition for space and nutrients, mycoparasitism, and possible antibiosis. Temperature and water activity significantly influenced fungal growth rate.

-Trichoderma harzianum has been found to be a competitor and mycoparasite of Fusarium verticillioides which causes foot rot disease on rice. The experiment was undertaken macroscopically and microscopically. In total 6 treatments were performed combining three water activities (0.95, 0.98, 0.995) and two temperatures (15 and 25 °C). At all conditions tested, except at 0.95 α w and 15 °C. Trichoderma harzianum acted as biocontrol agent trough two synergistic mechanisms -competition and mycoparasitism -over F. verticillioides. At 0.95 α w and 15 °C mutual antagonism by contact was observed. The effect of abiotic factors water activity and temperature on fungal growth was determined.

Chemical composition of commercial Origanum compactum and Cinnamomum zeylanicum essential oils and the antifungal activity against pathogenic fungi isolated from Mediterranean rice grains have been investigated. Sixty-one compounds accounting for more than 99.5% of the total essential oil were identified by using gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). Carvacrol (43.26%), thymol (21.64%) and their biogenetic precursors p-cymene (13.95%) and γ-terpinene (11.28%) were the main compounds in oregano essential oil, while the phenylpropanoids, eugenol (62.75%), eugenol acetate (16.36%) and (E)-cinnamyl acetate (6.65%) were found in cinnamon essential oil. Both essential oils at 300 μg/mL showed antifungal activity against all tested strains. O. compactum essential oil showed the best antifungal activity towards Fusarium species and Bipolaris oryzae with a total inhibition of the mycelial growth. In inoculated rice grains at lower doses (100 and 200 μg/mL) significantly reduced the fungal infection, so O. compactum essential oil could be used as ecofriendly preservative for field and stored Valencia rice.