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The soft rot disease caused by Rhizopus stolonifer is an important disease in cherry tomato fruit. In this study, the effect of iturin A on soft rot of cherry tomato and its influence on the storage quality of cherry tomato fruit were investigated. The results showed that 512 μg/mL of iturin A could effectively inhibit the incidence of soft rot of cherry tomato fruit. It was found that iturin A could induce the activity of resistance-related enzymes including phenylalanine ammonia lyase (PAL), polyphenol oxidase (PPO), peroxidase (POD), glucanase (GLU), and chitinase (CHI), and active oxygen-related enzymes including ascorbate peroxidases (APX), superoxide dismutases (SOD), catalases (CAT), and glutathione reductase (GR) of cherry tomato fruit. In addition, iturin A treatment could slow down the weight loss of cherry tomato and soften the fruit. These results indicated that iturin A could retard the decay and improve the quality of cherry tomato fruit by both the inhibition growth of R. stolonifera and the inducing the resistance.

This study attempted to characterize the involvement of a change in the redox status and subcellular localization in the BABA-induced priming resistance of peach fruit against Rhizopus rot. Specifically, 50 mM BABA primed the peaches for the enhanced disease resistance against R. stolonifer, as demonstrated by suppression of the disease development upon pathogen challenge accompanied by the clearly elevated level of TGA transcription factor (PpTGA1) and NPR1 gene (PpNPR1). In addition, the BABA elicitation enhanced the activities of a series of critical enzymes in the PPP and AsA-GSH cycle, and eventually promoted the NADPH and GSH pools, which altered the intracellular redox state towards a highly reductive condition. Additionally, PpTGA1-GFP was localized in the cytoplasm in the absence of BABA treatment or R. stolonifer inoculation, while BABA elicitation plus R. stolonifer inoculation caused PpTGA1-GFP to specifically translocate to the nucleus, where it interacted with PpNPR1 and regulated the positive expression of PR genes. Therefore, the observations implied that BABA could promote the reduction of the redox state, resulting in the translocation of PpTGA1 to the nucleus, which was a prerequisite for the induction of a priming defence against Rhizopus rot in peach.

The aim of this work was to investigate the early detection of anthracnose and soft rot diseases in cold stored strawberry fruit by evaluating the CO 2 and volatile organic compounds (VOCs) released by the fungi Colletotrichum fragariae and Rhizopus stolonifer. Strawberries were stored at 5, 10 and 21 °C (control group) and the VOCs and CO 2 production of inoculated and non-inoculated strawberries were followed by gas chromatography. To evaluate and estimate the growth of both fungi, the CO 2 data were fitted to the Gompertz model. Data of the VOCs released at the end of the fungal growth were analyzed using principal components analysis (PCA) to discriminate between infected and non-infected strawberries. The results showed that fungal growth was affected by temperature and C. fragariae had a maximum growth after 14.6 h at 5 °C and R. stolonifer at 21 °C after 45.2 h. On the other hand, through VOCs released by C. fragariae and R. stolonifer and PCA, four groups were obtained: a) strawberry infected with C. fragariae, stored at 10 °C, b) strawberry infected with R. stolonifer, stored at 21 °C, c) control group kept at 10 °C and, d) strawberry infected with C. fragariae and control group (5 and 21 °C), and strawberry infected with R. stolonifer at 5 and 10 °C. In conclusion, CO 2 and VOCs released by C. fragariae and R. stolonifer on strawberries could infer the presence of anthracnose and soft rot during storage of the fruit at low temperature., (Copyright © 2019 Elsevier GmbH. All rights reserved.)

The inhibitory effect of Bacillomycin D, a cyclic lipopeptide, on Rhizopus stolonifer colonization of cherry tomato was studied, and its possible mechanism of action was explored. Bacillomycin D showed a direct inhibitory effect on R. stolonifer spore germination and mycelial growth in vitro. It conferred both a direct inhibitory effect on R. stolonifer growth in cherry tomato in vivo and induced host resistance in cherry tomato. Moreover, Bacillomycin D treatment significantly increased the activities of plant defense-related enzymes, including chitinase (CHI), β-1,3-glucanase (GLU), phenylalanine ammonia-lyase (PAL), and peroxidase (POD). Real-time PCR (RT-PCR) showed that defense-related genes involved in the salicylic acid defense signaling pathway and genes encoding pathogenesis-related proteins were up-regulated in Bacillomycin D treatment. Furthermore, Bacillomycin D-C16 resulted in direct inhibition and a remarkable induced resistance to R. stolonifer which was higher than as induced by Bacillomycin D-C14. Together, the data indicated that Bacillomycin D can control the growth of R. stolonifer through both the direct inhibition of the fungus and the activation of defense-related genes and enzymes in cherry tomato.

The effect of temperature on the mycelium growth kinetics of four postharvest fungal isolates (i.e., Penicillium expansum, Alternaria alternata, Botrytis cinerea and Rhizopus stolonifer) was assessed. A cardinal model with inflection (CMI) was used to describe the effect of the temperature on the growth rate (μ) and the lag time (λ) of each isolate. Cardinal temperature values such as T min , T max and T opt were estimated and isolates were sorted according to their growth rate and lag time duration. Additionally, model validation was performed on a medium prepared from mashed pear pulp and on artificially wound-inoculated pear fruits. P. expansum was shown to be the most psychotrophic fungus with the lowest estimated T min  = -8.78. Model validation on pear pulp agar showed growth rate over-prediction in the case of R. stolonifer and B. cinerea but a good correlation in the case of P. expansum and A. alternata. In vivo experiments on pear fruits showed discrepancies from the synthetic and the simulated counterparts for all the fungi with the only exception of P. expansum., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Evolutions of phenolic contents and antioxidant activities during solid-state fermentation (SSF) of plum pomaces (from the juice industry) and brandy distillery wastes with Aspergillus niger and Rhizopus oligosporus were investigated. The effect of fermentation time on the oil content and major lipid classes in the plum kernels was also studied. Results showed that total phenolic (TP) amounts increased by over 30% for SSF with Rhizopus oligosporus and by >21% for SSF with A. niger. The total flavonoid contents presented similar tendencies to those of the TPs. The free radical scavenging activities of methanolic extracts were also significantly enhanced. The HPLC-MS analysis showed that quercetin-3-glucoside was the major phenolic compound in both fermented plum by-products. The results also demonstrated that SSF not only helped to achieve higher lipid recovery from plum kernels, but also resulted in oils with better quality attributes (high sterol ester and n-3 PUFA-rich polar lipid contents)., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Background: Oregano essential oil (EO) was incorporated into film-forming dispersions (FFDs) based on biopolymers (chitosan and/or methylcellulose) at two different concentrations. The effect of the application of the FFDs was evaluated on tomato plants (cultivar Micro-Tom) at three different stages of development, and on pre-harvest and postharvest applications on tomato fruit., Results: The application of the FFDs at '3 Leaves' stage caused phytotoxic problems, which were lethal when the EO was applied without biopolymers. Even though plant growth and development were delayed, the total biomass and the crop yield were not affected by biopolymer-EO treatments. When the FFDs were applied in the 'Fruit' stage the pre-harvest application of FFDs had no negative effects. All FFDs containing EO significantly reduced the respiration rate of tomato fruit and diminished weight loss during storage. Moreover, biopolymer-EO FFDs led to a decrease in the fungal decay of tomato fruit inoculated with Rhizopus stolonifer spores, as compared with non-treated tomato fruit and those coated with FFDs without EO., Conclusion: The application of biopolymer-oregano essential oil coatings has been proven to be an effective treatment to control R. stolonifer in tomato fruit. © 2016 Society of Chemical Industry., (© 2016 Society of Chemical Industry.)

In this study, we evaluated the efficacy of coatings comprising shrimp chitosan (CHI) and Mentha piperita L. (MPEO) or Mentha × villosa Huds (MVEO) essential oils to control mold infections caused by Aspergillus niger, Botrytis cinerea, Penicillium expansum and Rhizopus stolonifer in cherry tomato fruits (Solanum lycopersicum L.) during storage at room temperature (25°C for 12 days) and low temperature (12°C for 24 days). The effects of the coatings on the physicochemical and sensory characteristics of cherry tomato fruits during storage were also assessed. The minimum inhibitory concentration (MIC) of CHI against all test fungi was 8 mg/mL, whereas the MIC for both MPEO and MVEO was 5 μL/mL. Combinations of CHI at 4 mg/mL and MPEO or MVEO at 2.5 or 1.25 μL/mL strongly inhibited the mycelial growth and spore germination of target fungi. The coatings comprising CHI and MPEO or CHI and MVEO at the different tested concentrations delayed the growth of decay-causing fungi in artificially contaminated tomato fruit during storage at either room temperature or low temperature. The assayed coatings preserved the quality of cherry tomato fruit during storage, in terms of physicochemical and sensory attributes. These results indicate that coatings comprising CHI and MPEO or CHI and MVEO represent promising postharvest treatments to prevent common postharvest mold infections in cherry tomato fruit during storage without affecting the quality of the fruit., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Two nectarine cultivars ('Flavela' and 'Flanoba') were treated with Aloe vera gel alone, or with the addition of thymol, and then inoculated with Rhizopus stolonifer, Botrytis cinerea and Penicillium digitatum. Both treatments were effective in reducing the decay incidence caused by the 3 fungi species, although the addition of thymol did not generally improve the efficacy of Aloe vera gel on reducing the infection damage. The coatings were clearly effective in reducing the postharvest ripening process of both nectarine cultivars manifested by a delay in ethylene production and respiration rate, weight loss and softening. Interestingly, these coatings showed effectiveness on reducing decay development in inoculated fruits and thus Aloe vera could be considered as natural antifungal compound and might serve as alternative of synthetic fungicides., (Copyright © 2011 Elsevier B.V. All rights reserved.)

Treatment of stone fruits (apricot, peach and nectarine) with Pantoea agglomerans strain EPS125 decreased the incidence and diameter of lesions of brown rot caused by Monilinia laxa and soft rot caused by Rhizopus stolonifer. Root control was achieved on fruits either wounded and subsequently inoculated with the pathogens or non-wounded and naturally infected from orchards. The efficacy of biocontrol was dependent on the concentration of the biocontrol agent and pathogen. At medium to low pathogen dose, optimal EPS125 concentrations were above 10(7) CFU ml(-1). The median effective dose (ED(50)) of EPS125 was 4.5x10(4) in M. laxa and 2.2x10(5) CFU ml(-1) in R. stolonifer. However, EPS125 was more effective in M. laxa than in R. stolonifer as indicated by the ratio between ED(50) of the biocontrol agent and pathogen (K(z)/K(x)) which was 166 and 1263, respectively. Interactions between the strain EPS125 and the fruit surface, and M. laxa and R. stolonifer, were studied to determine the mechanisms of protection from postharvest rots. The strain EPS125 colonizes, grows and survives on stone fruit wounds. Significant inhibition of conidial germination and hyphal growth of R. stolonifer and M. laxa was achieved when the fungal and EPS125 cells were cocultivated on peel leachate or nectarine juice. However, no effect was observed when the antagonist and the pathogen cells were physically separated by a membrane filter which permits nutrient and metabolite interchange. Therefore, a direct interaction between the strain and the pathogen cells is necessary for antagonism, without a significant contribution of the production of antibiotic substances or nutrient competition. Preemptive exclusion by wound colonization and direct interaction with the pathogen is proposed as the mechanism of biocontrol.

The various mold count methods for nectars, purees, and pastes make no adjustment for concentration of the pulped liquid. Thus, mold counts of different forms of the same product (e.g., guava nectar, puree, or paste) or of the same product from different manufacturers cannot be compared. A method was developed in which the product is centrifuged under standardized conditions, then diluted to a standard pellet-to-final-volume ratio. Because variations in the concentration of fruit or vegetable tissue are corrected, comparisons of mold counts are possible. The method was adopted official first action.