Changes in the Fungal Community Assembly of Apple Fruit Following Postharvest Application of the Yeast Biocontrol Agent Metschnikowia fructicola

Recently, increasing focus has been placed on exploring fruit microbiomes and their association with their hosts. Investigation of the fruit surface microbiome of apple has revealed variations in the composition and structure depending on management practices, phenological stages, and spatial distribution on the fruit itself. However, the fate of the fruit surface microbiome assembly and dynamics in apple following interventions such as the application of biocontrol agents remains unknown. The objective of the study was to explore the effect of a postharvest application of a yeast biocontrol agent, Metschnikowia fructicola, on the composition of the epiphytic fungal microbiota on apples during cold storage. Our results demonstrated that the applied biocontrol agent, M. fructicola, persisted in high abundance (>28% relative abundance) on the fruit surface throughout the storage period. The biocontrol application significantly decreased the richness and caused a significant shift in the overall composition and structure of the fungal microbiome relative to untreated or water-treated controls. The yeast application reduced the abundance of several apple fungal pathogens, namely, Alternaria, Aspergillus, Comoclatris, Stemphylium, Nigrospora, Penicillium, and Podosphaera, throughout the cold storage period.

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Longitudinal Characterization of the Gut Bacterial and Fungal Communities in Yaks

Journal of Fungi ◽

10.3390/jof7070559 ◽

2021 ◽

Vol 7 (7) ◽

pp. 559

Author(s):

Yaping Wang ◽

Yuhang Fu ◽

Yuanyuan He ◽

Muhammad Fakhar-e-Alam Kulyar ◽

Mudassar Iqbal ◽

...

Keyword(s):

Natural Aging ◽

Fungal Communities ◽

Significant Shift ◽

Mature Adult ◽

Bacterial Phyla ◽

Development Stages ◽

Composition And Structure ◽

Intestinal Functions ◽

Development Phases

Development phases are important in maturing immune systems, intestinal functions, and metabolism for the construction, structure, and diversity of microbiome in the intestine during the entire life. Characterizing the gut microbiota colonization and succession based on age-dependent effects might be crucial if a microbiota-based therapeutic or disease prevention strategy is adopted. The purpose of this study was to reveal the dynamic distribution of intestinal bacterial and fungal communities across all development stages in yaks. Dynamic changes (a substantial difference) in the structure and composition ratio of the microbial community were observed in yaks that matched the natural aging process from juvenile to natural aging. This study included a significant shift in the abundance and proportion of bacterial phyla (Planctomycetes, Firmicutes, Bacteroidetes, Spirochaetes, Tenericutes, Proteobacteria, and Cyanobacteria) and fungal phyla (Chytridiomycota, Mortierellomycota, Neocallimastigomycota, Ascomycota, and Basidiomycota) across all development stages in yaks. As yaks grew older, variation reduced, and diversity increased as compared to young yaks. In addition, the intestine was colonized by a succession of microbiomes that coalesced into a more mature adult, including Ruminococcaceae_UCG-005, Romboutsia, Prevotellaceae_UCG-004, Blautia, Clostridium_sensu_stricto_1, Ruminococcus_1, Ruminiclostridium_5, Rikenellaceae_RC9_gut_group, Alloprevotella, Acetitomaculum, Lachnospiraceae_NK3A20_group, Bacteroides, Treponema_2, Olsenella, Escherichia-Shigella, Candidatus_Saccharimonas, and fungal communities Mortierella, Lomentospora, Orpinomyces, and Saccharomyces. In addition, microorganisms that threaten health, such as Escherichia-Shigella, Mortierella, Lomentospora and Hydrogenoanaerobacterium, Corynebacterium_1, Trichosporon, and Coprinellus, were enriched in young and old yaks, respectively, although all yaks were healthy. The significant shifts in microflora composition and structure might reflect adaptation of gut microbiome, which is associated with physicochemical conditions changes and substrate availability in the gut across all development periods of yaks.

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Transcriptome Analysis of Pre-Storage 1-MCP and High CO2-Treated ‘Madoka’ Peach Fruit Explains the Reduction in Chilling Injury and Improvement of Storage Period by Delaying Ripening

International Journal of Molecular Sciences ◽

10.3390/ijms22094437 ◽

2021 ◽

Vol 22 (9) ◽

pp. 4437

Author(s):

Han Ryul Choi ◽

Min Jae Jeong ◽

Min Woo Baek ◽

Jong Hang Choi ◽

Hee Cheol Lee ◽

...

Keyword(s):

Cold Storage ◽

Transcriptome Analysis ◽

Molecular Mechanisms ◽

Chilling Injury ◽

Chemical Properties ◽

Storage Period ◽

Differentially Expressed ◽

Peach Fruit ◽

High Co2 ◽

Physico Chemical

Cold storage of peach fruit at low temperatures may induce chilling injury (CI). Pre-storage 1-MCP and high CO2 treatments were reported among the methods to ameliorate CI and reduce softening of peach fruit. However, molecular data indicating the changes associated with pre-storage 1-MCP and high CO2 treatments during cold storage of peach fruit are insufficient. In this study, a comparative analysis of the difference in gene expression and physico-chemical properties of fruit at commercial harvest vs. stored fruit for 12 days at 0 °C (cold-stored (CS), pre-storage 1-MCP+CS, and pre-storage high CO2+CS) were used to evaluate the variation among treatments. Several genes were differentially expressed in 1-MCP+CS- and CO2+CS-treated fruits as compared to CS. Moreover, the physico-chemical and sensory data indicated that 1-MCP+CS and CO2+CS suppressed CI and delayed ripening than the CS, which could lead to a longer storage period. We also identified the list of genes that were expressed commonly and exclusively in the fruit treated by 1-MCP+CS and CO2+CS and compared them to the fruit quality parameters. An attempt was also made to identify and categorize genes related to softening, physiological changes, and other ripening-related changes. Furthermore, the transcript levels of 12 selected representative genes from the differentially expressed genes (DEGs) in the transcriptome analysis were confirmed via quantitative real-time PCR (qRT-PCR). These results add information on the molecular mechanisms of the pre-storage treatments during cold storage of peach fruit. Understanding the genetic response of susceptible cultivars such as ‘Madoka’ to CI-reducing pre-storage treatments would help breeders release CI-resistant cultivars and could help postharvest technologists to develop more CI-reducing technologies.

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Assessing the Potential of Algae Extracts for Extending the Shelf Life of Rainbow Trout (Oncorhynchus mykiss) Fillets

Foods ◽

10.3390/foods10050910 ◽

2021 ◽

Vol 10 (5) ◽

pp. 910

Author(s):

María I. Sáez ◽

María D. Suárez ◽

Francisco J. Alarcón ◽

Tomás F. Martínez

Keyword(s):

Rainbow Trout ◽

Cold Storage ◽

Haematococcus Pluvialis ◽

Radical Scavenging ◽

Storage Period ◽

Carotenoid Content ◽

Total Phenolic ◽

Antioxidant Power ◽

Color Parameters ◽

Total Carotenoid Content

This study evaluates the potential of different algae extracts (Crassiphycus corneus, Cc; Ulva ohnoi, Uo; Arthrospira platensis, Ap; Haematococcus pluvialis, Hp) as additives for the preservation of rainbow trout fillets. The extracts were prepared with different water to ethanol ratios from the four algae species. The highest ferric reducing antioxidant power (FRAP) was observed in Uo extracted in 80% ethanol. Ap aqueous extract also had considerable FRAP activity, in agreement with a high total phenolic content. Radical scavenging activity (DPPH) was higher in Cc 80% ethanol extract, in agreement with a high total carotenoid content. In fact, when the algae aqueous extracts were assayed on the fish fillets, their antioxidant activity exceeded that of ascorbic acid (ASC). All algae extracts delayed microbial growth and lipid oxidation processes in trout fillets throughout the cold storage period compared to controls, and also improved textural parameters, these effects being more evident for Ap and Hp. With respect to the color parameters, the Hp extract prevented the a* values (redness) from decreasing throughout cold storage, a key point when it comes to colored species, not least salmonids. On the other hand, the Ap extract was not as effective as the rest of treatments in avoiding a* and b* decrease throughout the storage period, and thereby the color parameters were impaired. The results obtained, together with the natural origin and the viability for large-scale cultivation, make algae extracts interesting fish preservative agents for the food industry.

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Effect of Harvest Date on Mango (Mangifera Indica L. Cultivar Osteen) Fruit’s Qualitative Development, Shelf Life and Consumer Acceptance

Agronomy ◽

10.3390/agronomy11040811 ◽

2021 ◽

Vol 11 (4) ◽

pp. 811

Author(s):

Giuseppe Gianguzzi ◽

Vittorio Farina ◽

Paolo Inglese ◽

Maria Gloria Lobo Rodrigo

Keyword(s):

Management Practices ◽

Mangifera Indica ◽

Storage Period ◽

Environmental Parameters ◽

Internal Quality ◽

Harvest Management ◽

Post Harvest ◽

Full Flowering ◽

Constant Quality ◽

Definition Of

The qualitative characteristics of mango fruits change throughout their development process and are also influenced by their duration. Harvesting at different times after the fruit set affects external and internal quality and the post-harvest behavior and management possibilities of the fruits. The objective of this study was to assess the evolution of the most important physicochemical and organoleptic parameters of cv. Osteen fruits concern the length of their stay on the plant and also to their post-harvest management. For this reason, fruits were harvested progressively in ten pickings. The study showed that mango fruits that are kept on the tree reach the best quality traits, corresponding to their physiological maturation. The length of the storage period needed to reach the consumption point varies greatly according to the harvesting moment and to the different environmental parameters, which also affect the organoleptic and physicochemical quality of the fruits. The number of days after full flowering were confirmed to be the primary information to consider when planning harvest with commercial use of the fruit, but interesting indications can be acquired through the definition of non-destructive (hardness, color) or destructive (dry matter) parameters. The data collected help improve mango fruit′s post-harvest management practices, to provide a product with constant quality and homogeneity to the consumer.

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Postharvest application of oxalic acid to preserve overall appearance and nutritional quality of fresh-cut green and purple asparagus during cold storage: a combined electrochemical and mass-spectrometry analysis approach

Postharvest Biology and Technology ◽

10.1016/j.postharvbio.2018.10.016 ◽

2019 ◽

Vol 148 ◽

pp. 158-167 ◽

Cited By ~ 6

Author(s):

Antonio Barberis ◽

Maria Cefola ◽

Bernardo Pace ◽

Emanuela Azara ◽

Ylenia Spissu ◽

...

Keyword(s):

Mass Spectrometry ◽

Oxalic Acid ◽

Cold Storage ◽

Nutritional Quality ◽

Mass Spectrometry Analysis ◽

Analysis Approach ◽

Spectrometry Analysis ◽

Postharvest Application ◽

Fresh Cut

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Effects of Storage Temperature and Preservative Treatment on Shelf Life of the Pond-Raised Freshwater Fish, Silver Perch (Bidyanus bidyanus)

Journal of Food Protection ◽

10.4315/0362-028x-64.10.1584 ◽

2001 ◽

Vol 64 (10) ◽

pp. 1584-1591 ◽

Cited By ~ 39

Author(s):

A. GELMAN ◽

L. GLATMAN ◽

V. DRABKIN ◽

S. HARPAZ

Keyword(s):

Shelf Life ◽

Cold Storage ◽

Storage Temperature ◽

Storage Period ◽

Potassium Sorbate ◽

Test Results ◽

Bacterial Composition ◽

Fish Flesh ◽

Microbiological Characteristics ◽

Initial Load

Sensory and microbiological characteristics of pond-raised freshwater silver perch (Bidyanus bidyanus) fish, during cold storage over a period of 25 days were evaluated. Whole fish (averaging 400 g each) were stored in cold storage rooms at either 0 to 2°C, 5°C, or 5°C + potassium sorbate as a preservative. The organoleptic and hypoxanthine test results show that the treatment of potassium sorbate can slow the process of spoilage by about 5 days. Yet, the most important factor affecting the shelf life of these fish is the storage temperature. Keeping the fish at 0 to 2°C can prolong the storage prior to spoilage by 10 days compared with those kept at 5°C. These results obtained through organoleptic tests are corroborated by both the chemical (hypoxanthine and total volatile basic nitrogen) and to some extent by the physical (cosmos) tests. The initial total bacteriological counts were 5 × 102 CFU/cm2 for fish surface and <102 CFU/g for fish flesh, and these counts rose continuously, reaching about 106 CFU/g (0 to 2°C) and 107 CFU/g (5°C) in flesh and 107 to 108 CFU/cm2 on the surface by the end of the storage period. The addition of potassium sorbate led to a smaller increase in bacterial numbers, especially during the first 15 days. Bacterial composition fluctuated during storage. The initial load on the fish surface was predominantly mesophilic and gram positive and consisted mostly (80%) of Micrococci, Bacillus, and Corynebacterium. During the next 10 days, these bacteria were practically replaced by gram-negative flora comprised mostly of Pseudomonas fluorescens that rapidly increased with storage time and accounted for 95% after 15 days.

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First Report of a Leaf Spot on Conyza sumatrensis Caused by Phoma macrostoma in China

Plant Disease ◽

10.1094/pdis-03-11-0228 ◽

2012 ◽

Vol 96 (1) ◽

pp. 148-148 ◽

Cited By ~ 1

Author(s):

J. Liu ◽

H. D. Luo ◽

W. Z. Tan ◽

L. Hu

Keyword(s):

Leaf Spot ◽

Fungal Pathogens ◽

Biological Diversity ◽

Biocontrol Agent ◽

Continuous Light ◽

The United States ◽

Leaf Spot Disease ◽

Pathogenicity Test ◽

Dry Land ◽

First Report

Conyza sumatrensis (Asteraceae), an annual or biennial plant, is native to North and South America. It is an invasive, noxious weed that is widespread in southern and southeastern China. It invades farm land and causes great losses to dry land crops, including wheat, corn, and beans. It also reduces biological diversity by crowding out native plants in the infested areas (3,4). During a search for fungal pathogens that could serve as potential biological control agents of C. sumatrensis, a leaf spot disease was observed in 2010 in Chongqing, China. An isolate (SMBC22) of a highly virulent fungus was obtained from diseased leaves. Pathogenicity tests were performed by placing 6-mm-diameter mycelial disks of 7-day-old potato dextrose agar (PDA) cultures of SMBC22 on leaves of 15 healthy greenhouse-grown plants of C. sumatrensis; the same number of control plants was treated with sterile PDA disks. Treated plants were covered with plastic bags for 24 h and maintained in a growth chamber with daily average temperatures of 24 to 26°C, continuous light (3,100 lux), and high relative humidity (>90%). Lesions similar to those observed in the field were first obvious on the SMBC22-inoculated leaves 3 days after inoculation. Symptoms became severe 7 to 9 days after inoculation. Control plants remained healthy. The fungus was reisolated from inoculated and diseased leaves and it was morphologically the same as SMBC22. The pathogenicity test was conducted three times. A survey of 10 southern and southeastern Chinese provinces revealed that the disease was widespread and it attacked leaves and stems of seedlings and mature plants of C. sumatrensis. Lesions on leaves were initially small, circular, and water soaked. The typical lesion was ovoid or fusiform, dark brown, and surrounded by a yellow halo. The spots coalesced to form large lesions and plants were often completely blighted. Fungal colonies of SMBC22 on PDA plates were initially white and turned dark gray. Colonies were circular with smooth edges with obvious rings of pycnidia on the surface. Aerial hyphae were short and dense. Pycnidia, black and immersed or semi-immersed in the medium, were visible after 12 days of incubation. Pycnidia were 72 to 140 μm in diameter. Conidia were produced in the pycnidia and were hyaline, unicellular, ellipsoidal, and 4.4 to 6.1 × 1.6 to 2.2 μm. To confirm identification of the fungus, genomic DNA was extracted from mycelia of a 7-day-old culture on PDA at 25°C (2). The internal transcribed spacer (ITS) gene of rDNA was amplified using primers ITS4/ITS5. The gene sequence was 524 bp long and registered in NCBI GenBank (No. HQ645974). BLAST analysis showed that the current sequence had 99% homology to an isolate of Phoma macrostoma (DQ 404792) from Cirsium arvense (Canada thistle) in Canada and reported to cause chlorotic symptoms on that host plant (1). To our knowledge, this is the first report of P. macrostoma causing disease on C. sumatrensis in China. P. macrostoma, thought of as a biocontrol agent of broadleaf weeds in Canada, has been patented in the United States. The current isolate of P. macrostoma is considered as a potential biocontrol agent of C. sumatrensis. References: (1) P. R. Graupner et al. J. Nat. Prod. 66:1558, 2004. (2) S. Takamatsu et al. Mycoscience 42:135, 2001. (3) W. Z. Tan et al. Page 177 in: Manual of Emergency Control Technology Invasive Pests in China. G. L. Zhang, ed. Science Press, Beijing, 2010. (4) C. Wang et al. J. Wuhan Bot. Res. 28:90, 2010.

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Lolium multiflorum seeds in the soil: I. Soil seed bank dynamics in a no til system

Revista Brasileira de Sementes ◽

10.1590/s0101-31222008000200013 ◽

2008 ◽

Vol 30 (2) ◽

pp. 100-110 ◽

Cited By ~ 2

Author(s):

Fernanda Costa Maia ◽

Manoel de Souza Maia ◽

Renée M. Bekker ◽

Rogério Previatti Berton ◽

Leandro Sebastião Caetano

Keyword(s):

Seed Bank ◽

Management Practices ◽

Transition Period ◽

Soil Seed Bank ◽

Lolium Multiflorum ◽

Storage Period ◽

Annual Ryegrass ◽

Seed Population ◽

Seed Bank Dynamics ◽

One Year

The objective of the study was to characterize annual ryegrass seed population dynamics, managed for natural re-sowing, in no til systems in rotation with soybean, in different chronosequences An area was cultivated for two years with soybean, left as fallow land for the next two years and then cultivated again with soybean for the next two years. The four chronosequences represented different management periods, two with soybean (6 and 8 years old) and the other two resting (3 and 9 years old). Soil samples were taken every month during one year and divided into two depths (0-5 and 5-10 cm). Vegetation dynamics were also evaluated (number of plants, inflorescences and seedlings). Soil seed bank (SSB) dynamics showed structural patterns in time, with a "storage period" in summer, an "exhausting period" during autumn and a "transition period" in winter and spring. Pasture establishment by natural re-sowing was totally dependent on the annual recruitment of seeds from the soil. The influence of the management practices on the SSB was more important than the number of years that these practices had been implemented. Places where soybean was sown showed the largest SSBs. Most of the seeds overcame dormancy and germinated at the end of the summer and beginning of the autumn, showing a typically transitory SSB, but with a small proportion of persistent seeds

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Identification of the Fungal Pathogens of Postharvest Disease on Peach Fruits and the Control Mechanisms of Bacillus subtilis JK-14

Toxins ◽

10.3390/toxins11060322 ◽

2019 ◽

Vol 11 (6) ◽

pp. 322 ◽

Cited By ~ 11

Author(s):

Shuwu Zhang ◽

Qi Zheng ◽

Bingliang Xu ◽

Jia Liu

Keyword(s):

Biological Control ◽

Bacillus Subtilis ◽

Fungal Pathogens ◽

Biological Control Agent ◽

Storage Period ◽

Control Agent ◽

Antagonistic Activity ◽

Postharvest Disease ◽

Economic Losses ◽

Control Mechanisms

Postharvest fungal disease is one of the significant factors that limits the storage period and marketing life of peaches, and even result in serious economic losses worldwide. Biological control using microbial antagonists has been explored as an alternative approach for the management of postharvest disease of fruits. However, there is little information available regarding to the identification the fungal pathogen species that cause the postharvest peach diseases and the potential and mechanisms of using the Bacillus subtilis JK-14 to control postharvest peach diseases. In the present study, a total of six fungal isolates were isolated from peach fruits, and the isolates of Alternaria tenuis and Botrytis cinerea exhibited the highest pathogenicity and virulence on the host of mature peaches. In the culture plates, the strain of B. subtilis JK-14 showed the significant antagonistic activity against the growth of A. tenuis and B. cinerea with the inhibitory rates of 81.32% and 83.45% at 5 days after incubation, respectively. Peach fruits treated with different formulations of B. subtilis JK-14 significantly reduced the mean disease incidences and lesion diameters of A. tenuis and B. cinerea. The greatest mean percent reduction of the disease incidences (81.99% and 71.34%) and lesion diameters (82.80% and 73.57%) of A. tenuis and B. cinerea were obtained at the concentration of 1 × 107 CFU mL−1 (colony forming unit, CFU). Treatment with the strain of B. subtilis JK-14 effectively enhanced the activity of the antioxidant enzymes-superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) in A. tenuis and B. cinerea inoculated peach fruits. As such, the average activities of SOD, POD and CAT were increased by 36.56%, 17.63% and 20.35%, respectively, compared to the sterile water treatment. Our results indicate that the isolates of A. tenuis and B. cinerea are the main pathogens that cause the postharvest peach diseases, and the strain of B. subtilis JK-14 can be considered as an environmentally-safe biological control agent for the management of postharvest fruits diseases. We propose the possible mechanisms of the strain of B. subtilis JK-14 in controlling of postharvest peach diseases.

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