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Mexico is among the most important citrus fruit producers in the world. However, during storage, several problems related to fungi can arise. The most common fungal postharvest diseases detected on Citrus limon var Eureka (Italian lime) produced in the Tamaulipas state are green/blue mold (Penicillium spp.), fusarium rot (F. oxysporum, F. solani, F. proliferatum, among others), and anthracnose (Colletotrichum spp.). In this work, we selected yeasts, occurring as the natural epiphytic mycoflora of lemons or from fermented traditional products, to be tested as part of a formulation for protecting stored lemons against fungal diseases. The best-performing yeasts, labeled as LCBG-03 (Meyerozyma guilliermondii), LCBG-30 (Pseudozyma sp.), and LCBG-49 (Saccharomyces cerevisiae), were selected to test their compatibility and biocontrol performance against strains of Penicillium digitatum (AL-38), Fusarium sp. (AL-21), Colletotrichum gloeosporioides (AL-13), and Epicoccum sorghinum (H3A). Based on their in vitro performance regarding the percentage of radial growth inhibition, both applied individually or as two yeasts mixed at equal cellular concentrations, the best combinations (containing M. guilliermondii formulated with either Pseudozyma sp. or S. cerevisiae) were selected with efficacies higher than 95% in both in vitro fungal radial growth rate inhibition and on stored lemon fruits. This work contributes to the search for compatible yeast combinations with the aim to diminish the fungal losses of citrus fruits using biocontrol for citrus postharvest protection. [ABSTRACT FROM AUTHOR]

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This study was made to identify the fungi associated with post-harvest decay in avocado fruit from Xalisco city in Nayarit state and to determine their potential biocontrol with Meyerozyma caribbica. The eight isolated fungi were identified as six Colletotrichum gloeosporioides, one Colletotrichum sp., and one Fusarium sp. through morphological characteristics and sequencing the D1/D2 region of the large-subunit rDNA gene. Koch's postulates were fulfilled by pathogenicity tests carried out on avocado fruit; obtaining different severity disease degrees. The yeasts' potential to control avocado diseases has been poorly studied. Therefore, the use of M. caribbica against the isolated fungi was proposed, the inhibition reached was above 78%. Hence, can be considered as a potential biocontrol agent to be applied in avocado fruit in the post-harvest stage. To our knowledge, this is the first report of Fusarium sp. as a causal agent of stem-end root in avocado fruit in Mexico. [ABSTRACT FROM AUTHOR]

Colletotrichum species are the most important postharvest spoilage fungi of papaya fruit. The objective of this research was to evaluate the effect of temperature and relative humidity on growth rate and time for growth to become visible of five strains of Colletotrichum gloeosporioides isolated from papaya fruit in a complex medium. As a primary model, the radial growth rates were estimated using the Baranyi and Roberts model in papaya agar. The Solver MS Excel function was used to obtain the time to visible mycelium (tv). Secondary models obtained with the Rosso et al. cardinal model of inflection were applied to describe the effect of temperature on the growth rate (μ). The Arrhenius-Davey model was used to model tv. The obtained models seem to be satisfactory for describing both μ and tv. The relative humidity had an effect on μ and tv for all tested C. gloeosporioides isolates, but no model accurately described the behavior of the fungus. External validation of models was performed with papaya fruit. Growth models were developed with the same models used in vitro. The bias and the accuracy factors as indices for performance evaluation of predictive models in food microbiology as a function of temperature and RH were 1.22 and 1.33, respectively, for μ and 1.18 and 1.62, respectively, for tv, indicating accurate predictions. The supply chain of papaya is complex and requires constant conditions, and poor conditions can result in damage to the fruit. Knowledge of the behavior of C. gloeosporioides on papaya fruit and application of the developed models in the supply chain will help to establish transport control strategies to combat these fungi. This research has contributed to development of the first models of growth for C. gloeosporioides in Mexico. Temperature greatly affected fungal rot of papaya at the postharvest stage. Fungal growth occurred when water was available, regardless of the relative humidity. Predictive models may help food processors make decisions for suboptimal supply chains. [ABSTRACT FROM AUTHOR]