Correlation between black point symptoms and fungal infestation and seedling viability of wheat kernels

The level of occurrence of black point, the spectrum of fungal species and damage to wheat seedling vigour associated with it were assessed during 2003 and 2004 in the Slovak Republic. The incidence of black point kernels ranged between 0.2–2.4% in 2003 and 24.2–34.3% in 2004. The kernels’ fungal contamination varied from 60% to 100%. Alternaria spp., F. poae and F. culmorum were isolated from all localities and all subsamples. Stemphylium vesicarium, Fusarium culmorum, F. graminearum, F. avenaceum, F. sporotrichioides, Microdochium nivale, Epicoccum nigrum, Penicillium spp., Aspergillus niger, Rhizopus nigricans and Cochliobolus sativus were isolated less frequently. Fungi of the genus Alternaria were the most dominant, followed by Fusarium and Microdochium among which F. poae was dominant. Irrespective of incubation temperature, the germinative capacity and coleoptile growth rate of discolored kernels were affected more in the wet and cold year 2004. The inhibition of germination and seedling viability was more pronounced at the incubation temperature 22°C than at 15°C. Inhibition of coleoptile growth rate was 0.12–3.12% in black point kernels collected in 2003, and 0.24–9.28% in those collected in 2004.

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Characterisation of Lactobacillus rhamnosus VT1 and its effect on the growth of Candida maltosa YP1

Czech Journal of Food Sciences ◽

10.17221/680-cjfs ◽

2008 ◽

Vol 25 (No. 5) ◽

pp. 272-282 ◽

Cited By ~ 2

Author(s):

D. Liptáková ◽

Ľ. Valík ◽

A. Lauková ◽

V. Strompfová

Keyword(s):

Growth Rate ◽

Incubation Temperature ◽

Lactobacillus Rhamnosus ◽

Microbial Interactions ◽

Lag Phase ◽

Regression Equations ◽

Candida Maltosa ◽

Food Protection ◽

Spoilage Yeast ◽

Standard Response

The combined effect of initial amount of 18 h L. rhamnosus VT1 inoculum and incubation temperature on the growth of Candida maltosa YP1, an oxidative food spoilage yeast strain, was primarily modelled and studied by standard response surface methodology. This study resulted in the following linear regression equations characterising lag time and growth rate of C. maltosa YP1 in milk in competition with the potentially protective lactobacillus strain. Lag-phase of C. maltosa was strongly influenced by the amount of lactobacillus inoculum (V0) and incubation temperature (1/T). The synergic effect of both these factors was also evident as results from the equation lag = –33.50 + 186.38 × V0 × 1/T + 512.27 × 1/T – 5.511 × V0 (R2(λ) = 0.849). The growth rate was sufficiently described by the linear relation: GrCm = –0.00046 + 0.0033 × T – 0.0016 × V0 (R2(Gr) = 0.847). On the basis of these equations, the mutual microbial interactions and the potential application of the lactobacillus strains to food protection are discussed.

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Volatile Organic Compound Profiles From Wheat Diseases Are Pathogen-Specific and Can Be Exploited for Disease Classification

Frontiers in Microbiology ◽

10.3389/fmicb.2021.803352 ◽

2022 ◽

Vol 12 ◽

Author(s):

Andrea Ficke ◽

Belachew Asalf ◽

Hans Ragnar Norli

Keyword(s):

Pure Culture ◽

Fusarium Culmorum ◽

Fungal Species ◽

Plant Diseases ◽

Disease Classification ◽

Diagnostic Tools ◽

Head Blight ◽

Wheat Varieties ◽

Wheat Diseases ◽

Volatile Organic

Plants and fungi emit volatile organic compounds (VOCs) that are either constitutively produced or are produced in response to changes in their physico-chemical status. We hypothesized that these chemical signals could be utilized as diagnostic tools for plant diseases. VOCs from several common wheat pathogens in pure culture (Fusarium graminearum, Fusarium culmorum, Fusarium avenaceum, Fusarium poae, and Parastagonospora nodorum) were collected and compared among isolates of the same fungus, between pathogens from different species, and between pathogens causing different disease groups [Fusarium head blight (FHB) and Septoria nodorum blotch (SNB)]. In addition, we inoculated two wheat varieties with either F. graminearum or P. nodorum, while one variety was also inoculated with Blumeria graminis f.sp. tritici (powdery mildew, PM). VOCs were collected 7, 14, and 21 days after inoculation. Each fungal species in pure culture emitted a different VOC blend, and each isolate could be classified into its respective disease group based on VOCs with an accuracy of 71.4 and 84.2% for FHB and SNB, respectively. When all collection times were combined, the classification of the tested diseases was correct in 84 and 86% of all cases evaluated. Germacrene D and sativene, which were associated with FHB infection, and mellein and heptadecanone, which were associated with SNB infection, were consistently emitted by both wheat varieties. Wheat plants infected with PM emitted significant amounts of 1-octen-3-ol and 3,5,5-trimethyl-2-hexene. Our study suggests that VOC blends could be used to classify wheat diseases. This is the first step toward a real-time disease detection in the field based on chemical signatures of wheat diseases.

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Chemotype and aggressiveness evaluation of Fusarium graminearum and Fusarium culmorum isolates from wheat fields in Wisconsin

Plant Disease ◽

10.1094/pdis-06-20-1376-re ◽

2021 ◽

Author(s):

Brian Mueller ◽

Carol Groves ◽

Damon L. Smith

Keyword(s):

Growth Rate ◽

Fusarium Head Blight ◽

Fusarium Graminearum ◽

Fusarium Culmorum ◽

Head Blight ◽

Growing Seasons ◽

Progress Curve ◽

Sporulation Capacity ◽

Derivatives Of

Fusarium graminearum commonly causes Fusarium head blight (FHB) on wheat, barley, rice, and oats. Fusarium graminearum produces nivalenol and deoxynivalenol (DON) and forms derivatives of DON based on its acetylation sites. The fungus is profiled into chemotypes based on DON derivative chemotypes (3 acetyldeoxynivalenol (3ADON) chemotype; 15 acetyldeoxynivalenol (15ADON) chemotype) and/or the nivalenol (NIV) chemotype. The current study assessed the Fusarium population found on wheat and the chemotype profile of the isolates collected from 2016 and 2017 in Wisconsin. Fusarium graminearum was isolated from all locations sampled in both 2016 and 2017. Fusarium culmorum was isolated only from Door County in 2016. Over both growing seasons, 91% of isolates were identified as the 15ADON chemotype while 9% of isolates were identified as the 3ADON chemotype. Aggressiveness was quantified by area under disease progress curve (AUDPC). The isolates with the highest AUDPC values were from the highest wheat producing cropping districts in the state. Deoxynivalenol production in grain and sporulation and growth rate in vitro were compared to aggressiveness in the greenhouse. Our results showed that 3ADON isolates in Wisconsin were among the highest in sporulation capacity, growth rate, and DON production in grain. However, there were no significant differences in aggressiveness between the 3ADON and 15ADON isolates. The results of this research detail the baseline frequency and distribution of 3ADON and 15ADON chemotypes observed in Wisconsin. Chemotype distributions within populations of F. graminearum in Wisconsin should continue to be monitored in the future.

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Biology, Management, and Protection of North American Sturgeon

Biology, Management, and Protection of North American Sturgeon ◽

10.47886/9781888569360.ch19 ◽

2002 ◽

Keyword(s):

Growth Rate ◽

Incubation Temperature ◽

Larval Survival ◽

Sampling Time ◽

White Sturgeon ◽

Green Sturgeon ◽

Acipenser Medirostris ◽

Relative Growth ◽

Klamath River ◽

Length Relationship

Abstract.—Gametes of green sturgeon Acipenser medirostris (caught in the Klamath River, California) and farm-reared white sturgeon A. transmontanus were obtained using hormonal induction of ovulation and spermiation. The offspring of one female in each species were reared in the laboratory, to compare their development and growth. Green and white sturgeon embryos had similar rates of development and hatched after 169 h and 176 h, respectively, at incubation temperature 15.7 ± 0.2°C. Embryos of both species exhibited similar holoblastic development and passed through 36 stages characteristic of acipenserids. Green sturgeon fertilization and hatching rates were 41.2% and 28.0%, compared with 95.4% and 82.1% for the white sturgeon. Larval survival to 45 d (metamorphosis) was 93.3% in green and 92.1% in white sturgeon. Newly hatched green sturgeon (length 13.7 ± 0.4 mm, mean ± SD) were larger and less pigmented, compared with white sturgeon. They had large ovoid yolk sacs and did not exhibit pelagic behavior that was observed in white sturgeon. The onset of exogenous feeding in green sturgeon occurred at age 10–15 d and length 24.0 ± 0.5 mm, and metamorphosis was completed at age 45 d and length 74.4 ± 5.9 mm (rearing temperature 18.5 ± 0.2°C). Weight and length of green sturgeon larvae and juveniles were considerably greater than in white sturgeon at each sampling time, but the relative growth rate and weight-length relationship were similar in both species. This suggests an effect of larger egg size and maternal yolk supply on the growth of green sturgeon. We conclude that green sturgeon differs from the white sturgeon in their reproductive strategy and, potentially, reproductive habitat.

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Description of a Novel Mycovirus in the Phytopathogen Fusarium culmorum and a Related EVE in the Yeast Lipomyces starkeyi

Viruses ◽

10.3390/v12050523 ◽

2020 ◽

Vol 12 (5) ◽

pp. 523

Author(s):

Mathieu Mahillon ◽

Gustavo Romay ◽

Charlotte Liénard ◽

Anne Legrève ◽

Claude Bragard

Keyword(s):

Retention Rate ◽

Fusarium Culmorum ◽

Fungal Species ◽

Dual Culture ◽

Isogenic Line ◽

Biological Characterization ◽

Lipomyces Starkeyi ◽

Fungal Host ◽

Dsrna Genome ◽

Novel Virus

A new mycovirus was found in the Fusarium culmorum strain A104-1 originally sampled on wheat in Belgium. This novel virus, for which the name Fusarium culmorum virus 1 (FcV1) is suggested, is phylogenetically related to members of the previously proposed family ‘’Unirnaviridae’’. FcV1 has a monopartite dsRNA genome of 2898 bp that harbors two large non-overlapping ORFs. A typical -1 slippery motif is found at the end of ORF1, advocating that ORF2 is translated by programmed ribosomal frameshifting. While ORF2 exhibits a conserved replicase domain, ORF1 encodes for an undetermined protein. Interestingly, a hypothetically transcribed gene similar to unirnaviruses ORF1 was found in the genome of Lipomyces starkeyi, presumably resulting from a viral endogenization in this yeast. Conidial isolation and chemical treatment were unsuccessful to obtain a virus-free isogenic line of the fungal host, highlighting a high retention rate for FcV1 but hindering its biological characterization. In parallel, attempt to horizontally transfer FcV1 to another strain of F. culmorum by dual culture failed. Eventually, a screening of other strains of the same fungal species suggests the presence of FcV1 in two other strains from Europe.

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Assessing Genetic Resistance in Wheat to Black Point Caused by Six Fungal Species in the Yellow and Huai Wheat Area of China

Plant Disease ◽

10.1094/pdis-01-20-0018-re ◽

2020 ◽

Vol 104 (12) ◽

pp. 3131-3134

Author(s):

Qiaoyun Li ◽

Mengyu Li ◽

Yumei Jiang ◽

Siyu Wang ◽

Kaige Xu ◽

...

Keyword(s):

Disease Incidence ◽

Genetic Resistance ◽

Bipolaris Sorokiniana ◽

Triticum Aestivum L ◽

Fungal Species ◽

Field Conditions ◽

Sources Of Resistance ◽

Black Point ◽

Environmentally Sustainable ◽

Resistant Cultivars

The most effective and environmentally sustainable method for controlling black point disease of wheat (Triticum aestivum L.) is to plant resistant cultivars. To identify sources of resistance to black point, 165 selected cultivars/lines were inoculated with isolates of six fungal species (Bipolaris sorokiniana, Alternaria alternata, Fusarium equiseti, Exserohilum rostratum, Epicoccum sorghinum, and Curvularia spicifera) known to cause black point in wheat using spore suspensions under controlled field conditions in 2016 and 2017. Inoculation of the isolates significantly increased the incidence of black point in the cultivars/lines compared with those grown under natural field conditions (NFC). The disease incidence of plants inoculated with B. sorokiniana and E. rostratum was 15.5% and 18.8% in 2016, and 20.4% and 23.0% in 2017, whereas those under NFC were 5.7% (2016) and 1.5% (2017), respectively. Furthermore, disease symptoms varied with pathogen. Among the 165 cultivars/lines tested, 3.6%, 50.9%, 60.0%, 1.8%, 47.3%, and 58.8% were resistant to B. sorokiniana, A. alternata, F. equiseti, E. rostratum, E. sorghinum, and C. spicifera, respectively. In addition, we identified one line (‘SN530070’) resistant to black point caused by all six pathogens. This is the first study to assess resistance to wheat black point caused by six fungal species under controlled conditions. The black point-resistant cultivars/lines could be useful in breeding and also in research on the mechanisms of resistance to black point.

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Growth characterisation of Staphylococcus aureus in milk: a quantitative approach

Czech Journal of Food Sciences ◽

10.17221/24/2009-cjfs ◽

2009 ◽

Vol 27 (No. 6) ◽

pp. 433-453 ◽

Cited By ~ 5

Author(s):

A. Medveďová ◽

Ľ. Valík ◽

Z. Sirotná ◽

D. Liptáková

Keyword(s):

Staphylococcus Aureus ◽

Growth Rate ◽

Incubation Temperature ◽

Food Poisoning ◽

Raw Milk ◽

Lag Phase ◽

Phase Duration ◽

Temperature Range ◽

Root Model ◽

Toxigenic Strains

Staphylococcus aureus is a pathogenic bacterium that induces several of human illnesses. The staphylococcal enterotoxin (SE) production as the results of previous growth of toxigenic strains is the most crucial problem which may lead to the staphylococcal food poisoning outbreaks in humans. That is why the growth of three strains of Staphylococcus aureus was characterised in milk and modelled in dependence of temperature. For the lag phase duration of S. aureus 2064, the Davey model was used with the following result: ln(1/lag) = 1.973 – 87.92/T + 285.09/T2 (R2 = 0.962). The dependence of the growth rate on incubation temperature was modelled by the Ratkowsky square root model and Gibson in sub-optimal and whole temperature range, respectively. The validation of both models showed high significance of the growth rate data fitting. The optimal temperature of Topt = 38.5°C was resulted from Gibson model for the S. aureus 2064 growth in milk. For practical purpose, the time necessary for the increase of S. aureus by 3 log counts was also calculated within the growth temperature range. These data may provide useful information e.g. for the producers using raw milk in their artisanal cheese practice as the specific strains were used in this study.

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Attach Me If You Can: Murine Norovirus Binds to Commensal Bacteria and Fungi

Viruses ◽

10.3390/v12070759 ◽

2020 ◽

Vol 12 (7) ◽

pp. 759 ◽

Cited By ~ 2

Author(s):

Jasmine L. Madrigal ◽

Sutonuka Bhar ◽

Samantha Hackett ◽

Haley Engelken ◽

Ross Joseph ◽

...

Keyword(s):

Incubation Temperature ◽

Growth Conditions ◽

Fungal Species ◽

Commensal Bacteria ◽

Murine Norovirus ◽

Human Norovirus ◽

Viral Pathogens ◽

Bacteria And Fungi ◽

The Impact ◽

Murine Noroviruses

The presence of commensal bacteria enhances both acute and persistent infection of murine noroviruses. For several enteric viral pathogens, mechanisms by which these bacteria enhance infection involve direct interactions between the virus and bacteria. While it has been demonstrated that human noroviruses bind to a variety of commensal bacteria, it is not known if this is also true for murine noroviruses. The goal of this study was to characterize interactions between murine noroviruses and commensal bacteria and determine the impact of bacterial growth conditions, incubation temperature and time, on murine norovirus attachment to microbes that comprise the mammalian microbiome. We show that murine noroviruses bind directly to commensal bacteria and show similar patterns of attachment as human norovirus VLPs examined under the same conditions. Furthermore, while binding levels are not impacted by the growth phase of the bacteria, they do change with time and incubation temperature. We also found that murine norovirus can bind to a commensal fungal species, Candida albicans.

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