Biological control employs beneficial microorganisms to suppress phytopathogens and mitigate the incidence of associated plant diseases. This study investigated the in vitro development and survival of Trichoderma spp. isolates derived from commercial formulations under different temperatures, pH levels, and sodium chloride (NaCl) concentrations and with synthetic fungicides with distinct modes of action. Three isolates were analyzed: URM-5911 and TRA-0048 (T. asperellum) and TRL-0102 (T. longibrachiatum). The results revealed substantial variability among the isolates, with the optimal mycelial growth temperatures ranging from 24.56 to 29.42 °C. All the isolates exhibited broad tolerance to the tested pH (5–9) and salinity levels (250–1000 mM), with TRL-0102 demonstrating the highest salt resistance. The fungicide treatments negatively affected mycelial growth across all the isolates, with Azoxystrobin + Difenoconazole and Boscalid causing growth reductions of up to 50%. Notably, Boscalid enhanced conidial production more compared to the control (126.0% for URM-5911, 13.7% for TRA-0048, and 148.5% for TRL-0102) and decreased the percentage of inactive conidia to less than 10% in all the isolates. These results provide strategic information for the application of Trichoderma spp. in agricultural systems, supporting the selection of more adapted and suitable isolates for integrated disease management programs.

Macrophomina (Botryosphaeriaceae) is one of the main genera of soilborne phytopathogenic fungi, which causes root and seed rot in more than 800 host plants worldwide. Recent phylogenetic studies identified the species M. phaseolina and M. pseudophaseolina in Trianthema portulacastrum and Boerhavia diffusa in melon and watermelon production areas in northeastern Brazil. Therefore, the objective of this study was: i) to verify the effect of temperature and salinity on the mycelial growth of M. phaseolina, M. pseudophaseolina and M. euphorbiicola, ii) to assess their pathogenicity on melon and watermelon seedlings, and iii) to determine their sensitivity to the fungicide carbendazim. The optimal temperature for mycelial growth rate (MGR) for Macrophomina spp. ranged from 27.18 ºC (CMM4771 – M. pseudophaseolina) to 31.80 ºC (CMM4763 – M. phaseolina). For the effect of salinity on mycelial growth of Macrophomina isolates, the EC50 ranged from 103.76 (CMM4868 – M. euphorbiicola) to 315.25 mM (CMM4801 – M. pseudophaseolina). The pathogenicity test demonstrated that M. phaseolina, M. pseudophaseolina and M. euphorbiicola are pathogenic on melon with M. phaseolina exhibiting a higher level of virulence. Macrophomina euphorbiicola isolates did not cause disease in watermelon. The most sensitive isolates to the fungicide carbendazim were CMM4868, CMM4867 (M. euphorbiicola) and CMM1531 (M. phaseolina) with EC50 of 0.003, 0.012 and 0.012 mg.L-1 a.i., respectively. All Macrophomina spp. used in these experiments were pathogenic to the tested melon and watermelon cultivars with the exception of the M. euphorbiicola isolate that did not cause damage to watermelon.

Heat treatment is used in the orange juice industry to neutralize the action of pathogenic microorganisms. However, it can reduce the nutritional value of the juice. Thus, our study assessed the cold plasma treatment as an alternative method against Escherichia coli and Candida albicans in 'Lima' orange juice. Both, plasma and heat treatments, reduced the amount of E. coli in the juice, inactivating 16.72 and 100%, respectively. Plasma did not inactivate C. albicans, but heat treatment inactivated 100%. Plasma and heat treatment increased Hue angle and luminosity (more yellowish juice). Plasma reduced vitamin C, carotenoids, and polyphenols content, while increased flavonoids. Heat treatment reduced the carotenoid content. However, neither heat nor plasma treatment altered the antioxidant activity. The plasma treatment reduced the intensity of color (chroma), the soluble solids content and the acidity ratio, total sugars, and the vitamin C content of juice compared to the heat-treated and control juices. Plasma-treated juice showed increased levels of yellow flavonoids, total phenolics and antioxidant activity until the 12^th day of storage.