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Bacillus velezensis TCS001 is a new type of marine biocontrol bacterium, which has broadspectrum antifungal activity and promotes plant growth, and has great potential for development in agricultural applications. In this study, the additives and proportions of wetting and dispersing additives, thickeners, and preservatives with high compatibility with TCS001 were screened using the toxic medium method, growth determination method and suspension performance evaluation method, and the formula of TCS001 suspension agent (TCS001 SC)was obtained. The screening results showed that the TCS001 SC formula was: 40% TCS001 fermentation broth(≥1010 CFU/mL), 3% wetting and dispersing additives SXC, 3% wetting and dispersing additives UNA, 0.15% thickener xanthan gum, 0.2% preservative Kathone, 0.2% preservative sodium benzoate. When the water was supplemented to100% (mass fraction), the number of viable bacteria of TCS001 SC developed was 4.0 × 109 CFU/mL, with a miscellaneous bacteria rate of 4.8%. For TCS001 SC, the pH value was 6.68, and the suspension rate was 97.8%. The pass rate through the 75 μm test sieve was 99.9%, and the mass fraction of residue after pouring was 1.6%, and after washing was 0.41%. And the long-lasting foaming property (after 1min)was 16 mL, all performances are in line with industry standards (NY/T 2989-2016). Further more, the storage stability of TCS001 SC was measured at different temperatures, there was no significant difference in the number of viable bacteria when stored at (0 ± 0.2)°C for 7 days and (4 ±0.2)°C for 360 days compared to before storage respectively, and the survival rate of bacterial cells was above 80% when stored at (28 ± 0.2)°C for 360 days and (35 ± 0.2)°C for 84 days, respectively indicating good storage stability. On this basis, the field test was carried out with strawberry anthracnose as the target, and the results showed that TCS001 SC 1500-3000 mL/hm² could significantly reduce the occurrence of strawberry anthracnose, and the control efficacy was between59.37%-79.52%. Among them, the control efficacy of 3000 mL/hm² spraied 3 times at 7 d intervals on strawberry anthracnose reached 79.52%, which provided a theoretical basis for the registration of TCS001 SC as a microbial fungicide for the prevention and control of strawberry anthracnose. [ABSTRACT FROM AUTHOR]

Strawberry anthracnose, caused by Colletotrichum spp., is a major disease that causes tremendous damage to cultivated strawberry plants (Fragaria × ananassa Duch.). Examining and distinguishing plants potentially carrying the pathogen is one of the most effective ways to prevent and control strawberry anthracnose disease. Herein, we used this method on Colletotrichum gloeosporioides at the crown site on indoor strawberry plants and established a classification and distinguishing model based on measurement of the spectral and textural characteristics of the disease-free zone near the disease center. The results, based on the successive projection algorithm (SPA), competitive adaptive reweighted sampling (CARS), and interval random frog (IRF), extracted 5, 14, and 11 characteristic wavelengths, respectively. The SPA extracted fewer effective characteristic wavelengths, while IRF covered more information. A total of 12 dimensional texture features (TFs) were extracted from the first three minimum noise fraction (MNF) images using a grayscale co-occurrence matrix (GLCM). The combined dataset modeling of spectral and TFs performed better than single-feature modeling. The accuracy rates of the IRF + TF + BP model test set for healthy, asymptomatic, and symptomatic samples were 99.1%, 93.5%, and 94.5%, the recall rates were 100%, 94%, and 93%, and the F1 scores were 0.9955, 0.9375, and 0.9374, respectively. The total modeling time was 10.9 s, meaning that this model demonstrated the best comprehensive performance of all the constructed models. The model lays a technical foundation for the early, non-destructive detection of strawberry anthracnose. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Shenyang Agricultural University is the property of Journal of Shenyang Agricultural University Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

AbstractStrawberry has high nutritional and economic value and is an important horticultural crop widely cultivated worldwide. Strawberry anthracnose is the most harmful disease in strawberry production, which causes huge production losses every year. Mining disease resistance genes and breeding high-quality strawberry varieties are the fundamental way to solve the problem of strawberry anthracnose. In this study, transcriptome analysis and disease resistance-related genes mining were targeted on strawberry anthracnose. The main results are as follows: (1) A total of 100.45 Gb clean reads were obtained, with no less than 6.26 Gb for each sample; (2) The clean reads for each sample were aligned to the reference genome efficiently at 91.30% − 92.27%; (3) 93,042 genes were annotated; (4) 16 anti-anthracnose-related genes were identified, including FaAUX1, FaARF18, FaSAUR50, FaGH3.6, FaAHP1, FaARR (3, 5 and 11), FaPYR1, FaPYL11, FaPP2C (6, 16, 24, 37 and 51) and FaPR1. The above results can provide theoretical guidance for the molecular breeding of disease resistance of strawberry.

Strawberry anthracnose, caused by Colletotrichum spp., is a major disease that causes tremendous damage to cultivated strawberry plants (Fragaria × ananassa Duch.). Examining and distinguishing plants potentially carrying the pathogen is one of the most effective ways to prevent and control strawberry anthracnose disease. Herein, we used this method on Colletotrichum gloeosporioides at the crown site on indoor strawberry plants and established a classification and distinguishing model based on measurement of the spectral and textural characteristics of the disease-free zone near the disease center. The results, based on the successive projection algorithm (SPA), competitive adaptive reweighted sampling (CARS), and interval random frog (IRF), extracted 5, 14, and 11 characteristic wavelengths, respectively. The SPA extracted fewer effective characteristic wavelengths, while IRF covered more information. A total of 12 dimensional texture features (TFs) were extracted from the first three minimum noise fraction (MNF) images using a grayscale co-occurrence matrix (GLCM). The combined dataset modeling of spectral and TFs performed better than single-feature modeling. The accuracy rates of the IRF + TF + BP model test set for healthy, asymptomatic, and symptomatic samples were 99.1%, 93.5%, and 94.5%, the recall rates were 100%, 94%, and 93%, and the F1 scores were 0.9955, 0.9375, and 0.9374, respectively. The total modeling time was 10.9 s, meaning that this model demonstrated the best comprehensive performance of all the constructed models. The model lays a technical foundation for the early, non-destructive detection of strawberry anthracnose.

Anthracnose caused by Colletotrichum spp. was widespread in recent years and resulted in great damage to strawberry production. Soil microbial communities were key contributors to host nutrition, development, and immunity; however, the difference between the microbial communities of healthy and anthracnose-infected strawberry rhizosphere soils remains unclear. In this study, the Illumina sequencing technique was used to comparatively study the prokaryotic and fungal community compositions and structures between healthy and anthracnose-infected strawberry rhizosphere soils in Yuxi, Yunnan Province. Both microbial community diversities and richness of anthracnose-infected strawberry rhizosphere soils were higher than those of healthy strawberry rhizosphere soils. A total of 2,518 prokaryotic and 556 fungal operational taxonomic units (OTUs) were obtained at the 97% similarity threshold. Proteobacteria, Thaumarchaeota, and Acidobacteria were the dominant prokaryotic phyla; Ascomycota, unclassified_k__Fungi, and Mortierellomycota were the dominant fungal phyla. The relative abundances of beneficial bacterial phyla Actinobacteria and Firmicutes, genera Streptomyces, Azospirillum , and Bacillus were significantly reduced in anthracnose-infected strawberry rhizosphere soils; the relative abundance of beneficial fungal species Trichoderma asperellum shows a similar tendency with bacterial abundance. Besides Colletotrichum , 15 other potential fungal pathogen genera and seven fungal pathogen species were identified; among the potential pathogen genera and species, eight pathogen genera and Fusarium oxysporum showed significant differences between healthy and anthracnose-infected strawberry rhizosphere soils. The results suggested that strawberry planted in this area may be infected by other fungal pathogens except for Colletotrichum spp. Our present research will provide theoretical basis and data reference for the isolation and identification of strawberry pathogens and potential probiotics in future works. [ABSTRACT FROM AUTHOR]

Anthracnose caused by Colletotrichum spp. was widespread in recent years and resulted in great damage to strawberry production. Soil microbial communities were key contributors to host nutrition, development, and immunity; however, the difference between the microbial communities of healthy and anthracnose-infected strawberry rhizosphere soils remains unclear. In this study, the Illumina sequencing technique was used to comparatively study the prokaryotic and fungal community compositions and structures between healthy and anthracnose-infected strawberry rhizosphere soils in Yuxi, Yunnan Province. Both microbial community diversities and richness of anthracnose-infected strawberry rhizosphere soils were higher than those of healthy strawberry rhizosphere soils. A total of 2,518 prokaryotic and 556 fungal operational taxonomic units (OTUs) were obtained at the 97% similarity threshold. Proteobacteria, Thaumarchaeota, and Acidobacteria were the dominant prokaryotic phyla; Ascomycota, unclassified_k__Fungi, and Mortierellomycota were the dominant fungal phyla. The relative abundances of beneficial bacterial phyla Actinobacteria and Firmicutes, genera Streptomyces, Azospirillum, and Bacillus were significantly reduced in anthracnose-infected strawberry rhizosphere soils; the relative abundance of beneficial fungal species Trichoderma asperellum shows a similar tendency with bacterial abundance. Besides Colletotrichum, 15 other potential fungal pathogen genera and seven fungal pathogen species were identified; among the potential pathogen genera and species, eight pathogen genera and Fusarium oxysporum showed significant differences between healthy and anthracnose-infected strawberry rhizosphere soils. The results suggested that strawberry planted in this area may be infected by other fungal pathogens except for Colletotrichum spp. Our present research will provide theoretical basis and data reference for the isolation and identification of strawberry pathogens and potential probiotics in future works.

Strawberry has high nutritional and economic value and is an important horticultural crop widely cultivated worldwide. Strawberry anthracnose is the most harmful disease in strawberry production, which causes huge production losses every year. Mining disease resistance genes and breeding high-quality strawberry varieties are the fundamental way to solve the problem of strawberry anthracnose. In this study, transcriptome analysis and disease resistance-related genes mining were targeted on strawberry anthracnose. The main results are as follows: (1) A total of 100.45 Gb clean reads were obtained, with no less than 6.26 Gb for each sample; (2) The clean reads for each sample were aligned to the reference genome efficiently at 91.30% − 92.27%; (3) 93,042 genes were annotated; (4) 16 anti-anthracnose-related genes were identified, including FaAUX1, FaARF18, FaSAUR50, FaGH3.6, FaAHP1, FaARR (3, 5 and 11), FaPYR1, FaPYL11, FaPP2C (6, 16, 24, 37 and 51) and FaPR1. The above results can provide theoretical guidance for the molecular breeding of disease resistance of strawberry. [ABSTRACT FROM AUTHOR]

Strawberry anthracnose (p ath o ge n Colletotrichum gloeosporioides) i s an i mportant disease in strawberries that becomes c hal lenging during an out break. In particular, if rain continues during the high -temperatu reseed ling raising period, it t ends to occur vio l ent l y, and fo r ou td oor s e edl in gs, ch e mi ca l con t rol durin g ra inf al l is i mpo rt ant . Therefore, we compared the effe c ts of t he ch e mi c al s and id en tif ie d thos e th at w e re l e as t aff ec t ed b y r ainf a ll . Fludio xoni l, p ro pin eb, and c ap tan w e tt ab le po wd e rs w e re s ta bl e and h i ghl y e ffe c ti ve e ven wh en used prior to th e rain commen cement, followed by man coze band diet hofe ncarb + thio ph ana t e -meth yl w e tt abl e powders. [ABSTRACT FROM AUTHOR]

• Volatile organic compounds (VOCs) produce by strain CG-G2 had antifungal activity. • VOCs keep fruit quality and inhibit the infection of Colletotrichum gloeosporioides. • VOCs cause collapse of fungal hyphae and inhibit spore germination. • Flavonoid induce by VOCs in strawberry fruit contributes to fungal resistance. • Methyl 2-methyl butyrate is a main component of antifungal activity in VOCs. Colletotrichum gloeosporioides is a fungal disease of strawberry fruit. Biocontrol strategies holds tremendous promise in alleviating fruit decay. Here, 30 actinomycetes were isolated from rhizosphere soil of Calotropis gigantea. A strain labeled with CG-G2 exhibited the strongest antagonistic activity against C. gloeosporioides and was assigned as Streptomyces corchorusii. Compared to strain CG-G2 extracts, the volatile organic compounds (VOCs) had a high antifungal activity against anthracnose. These volatiles effectively inhibited mycelial growth and spore germination of C. gloeosporioides. The hyphal and conidial structure was severely destroyed. Metabolomics analysis revealed that VOCs inhibited C. gloeosporioides via inducing flavonoids metabolism contributing to antifungal activity. Three main antagonistic compounds in VOCs were identified as methyl 2-methyl butyrate, hexanenitrile and methyl 2-Ethyl hexanoate. Especially, methyl 2-methyl butyrate demonstrated a remarkable efficacy in inhibiting fruit decay and preserving fruit quality. Hence, S. corchorusii CG-G2 will be a potential biocontrol agent for controlling anthracnose on harvested fruits. [ABSTRACT FROM AUTHOR]

Copyright of Acta Agriculturae Zhejiangensis is the property of Acta Agriculturae Zhejiangensis Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

[Display omitted] • We achieved unambiguous identification of strawberry anthracnose as early as 3 days after exposure to Colletotrichum gloeosporioides. • We found molecular markers associated with C. gloeosporioides and plant metabolites, such as fluorescence background, amide III, fatty acids, aromatic rings, and terpenoids. • Early on–site detection of strawberry anthracnose is possible using potable Raman system even without visible symptoms. We developed a method for the early on–site detection of strawberry anthracnose using a portable Raman system with multivariate statistical analysis algorithms. By using molecular markers based on Raman spectra, the proposed method can detect anthracnose in strawberry stems 3 days after exposure to Colletotrichum gloeosporioides. A fiber–optic probe was applied for the portable Raman system, and the acquisition time was 10 s. We found that the molecular markers were closely related to the following subjects: i) an increase in amide III and fatty acids of C. gloeosporioides invading strawberry stems (Raman bands at 1180–1310 cm−1) and ii) a decrease in metabolites in strawberry plants, such as phenolic compounds and terpenoids (Raman bands at 760, 800, and 1523 cm−1). We also found that the increased fluorescence background caused by various chromophores within the invading C. gloeosporioides could serve as a marker. A two–dimensional cluster plot obtained by principal component analysis (PCA) showed that the three groups (control, fungal infection, and pathogen) were distinguishable. The linear discriminant analysis (LDA)–based prediction algorithm could identify C. gloeosporioides infection with a posterior probability of over 40%, even when no symptoms were visible on the inoculated strawberry plants. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Henan Agricultural Sciences is the property of Editorial Board of Journal of Henan Agricultural Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Strawberry anthracnose caused by Colletotrichum gloeosporioides has recently become a major problem in Taiwan, in concurrence with herbicide use by growers. In evaluations of the effects of paraquat, glyphosate and glufosinate on C. gloeosporioides, anthracnose severity and soil microbial communities, paraquat and glyphosate promoted hyphal growth, conidial production and germination, and soil survival of C. gloeosporioides; glufosinate had inhibitory effects. Soil drench with glyphosate, but not paraquat or glufosinate, increased populations of fungi and yeast-like microorganisms. Anthracnose was more severe on leaves after either foliar sprays or drenches with paraquat or glyphosate than on controls without herbicide. Thus, a sudden outbreak of strawberry anthracnose is likely attributable to the stimulatory effects of herbicides on the causal pathogen. To minimize the inoculum potential of C. gloeosporioides and anthracnose severity, strawberry growers should eliminate any plant debris after herbicide treatment. [ABSTRACT FROM AUTHOR]

In this work, we present a novel biostimulant for sustainable crop disease management, PSP1, based on the plant defense-elicitor AsES, an extracellular protease produced by the strawberry fungal pathogen Acremonium strictum. Fungal fermentation conditions and downstream processing were determined to maximize extracellular protein production, product stability and a high plant defense-eliciting activity, as monitored by anthracnose resistance in supernatant-treated strawberry plants subsequently infected with a virulent strain of Colletotrichum acutatum. Fermentation batches were shown to reduce anthracnose development by 30–60% as compared to infected non-treated plants. Product formulation was shown to be stable for 6 months when stored at temperatures up to 45°C and toxicological tests showed that PSP1 was harmless to beneficial organisms and non-toxic to mammalian species at concentrations 50 times higher than those used in plant experiments. Furthermore, disease protection studies using dilutions of PSP1 indicated that there is a minimum threshold protease activity needed to induce pathogen defense in strawberry and that this induction effect is dose-independent. A significant characteristic of PSP1 is its broad-range protection against different diseases in various crop species. In soybean, PSP1 reduced the symptomatology by 70% of Corynespora cassiicola, etiological agent of the target spot. This protection effect was similar to the commercial inducer BION 500 WG based on BTH, and both products were shown to induce an oxidative burst and up-regulated PR1-gene expression in soybean. Furthermore, a double PSP1-treatment on greenhouse-grown sugarcane plants provided protection against bacterial red stripe disease caused by Acidovorax avenae and a double foliar application of PSP1 on field-grown wheat plants significantly increased resistance against Fusarium graminearum, causal agent of head blight disease, manifested mainly in an increased seed germination rate. In summary, these disease protection studies demonstrated an effective control against both bacterial and fungal pathogens in both monocot and dicot crop species, which together with its low production cost, effectiveness at low concentrations, long shelf-life, tolerance to high temperatures, harmlessness to non-target organisms and simple handling and application, make PSP1 a very promising candidate for effective and sustainable disease management in many crop species.

In this work, we present a novel biostimulant for sustainable crop disease management, PSP1, based on the plant defense-elicitor AsES, an extracellular protease produced by the strawberry fungal pathogen Acremonium strictum. Fungal fermentation conditions and downstream processing were determined to maximize extracellular protein production, product stability and a high plant defense-eliciting activity, as monitored by anthracnose resistance in supernatant-treated strawberry plants subsequently infected with a virulent strain of Colletotrichum acutatum. Fermentation batches were shown to reduce anthracnose development by 30–60% as compared to infected non-treated plants. Product formulation was shown to be stable for 6 months when stored at temperatures up to 45°C and toxicological tests showed that PSP1 was harmless to beneficial organisms and non-toxic to mammalian species at concentrations 50 times higher than those used in plant experiments. Furthermore, disease protection studies using dilutions of PSP1 indicated that there is a minimum threshold protease activity needed to induce pathogen defense in strawberry and that this induction effect is dose-independent. A significant characteristic of PSP1 is its broad-range protection against different diseases in various crop species. In soybean, PSP1 reduced the symptomatology by 70% of Corynespora cassiicola, etiological agent of the target spot. This protection effect was similar to the commercial inducer BION 500 WG based on BTH, and both products were shown to induce an oxidative burst and up-regulated PR1-gene expression in soybean. Furthermore, a double PSP1-treatment on greenhouse-grown sugarcane plants provided protection against bacterial red stripe disease caused by Acidovorax avenae and a double foliar application of PSP1 on field-grown wheat plants significantly increased resistance against Fusarium graminearum, causal agent of head blight disease, manifested mainly in an increased seed germination rate. In summary, these disease protection studies demonstrated an effective control against both bacterial and fungal pathogens in both monocot and dicot crop species, which together with its low production cost, effectiveness at low concentrations, long shelf-life, tolerance to high temperatures, harmlessness to non-target organisms and simple handling and application, make PSP1 a very promising candidate for effective and sustainable disease management in many crop species. [ABSTRACT FROM AUTHOR]

Colletotrichum fructicola is a major causal agent among anthracnose pathogens of strawberry in Nara, Japan. We hypothesized that a wide range of weeds growing in and around strawberry fields are inoculum sources of the disease and investigated their potential as hosts of C. fructicola. We also examined the influence of herbicide treatment on C. fructicola sporulation on weeds. The fungus was detected on 31 of 541 (5.7%) leaves sampled from 13 weed species from 2005 to 2008. The fungus was most frequently isolated from leaves of Amaranthus blitum with an isolation frequency of 17.9%; inoculation of A. blitum with the pathogen caused brown leaf spots. Other weeds such as Digitaria ciliaris, Galinsoga ciliata, Solidago altissima, Erigeron annuus, and Sonchus oleraceus were found to harbor the fungus at lower rates (4.3-8.1%) without symptoms. C. fructicola formed acervuli on leaves of A. blitum, D. ciliaris, and S. oleraceus after plants were killed by a herbicide (glyphosate). These results demonstrated that infected weeds associated with strawberry cultivation are potential inoculum sources of C. fructicola, especially after herbicide treatment. [ABSTRACT FROM AUTHOR]

We developed a loop-mediated isothermal amplification (LAMP) assay for detecting Colletotrichum gloeosporioides, which causes anthracnose, in strawberry plants. Primer sets targeted the region from the gene encoding 5.8S ribosomal RNA to internal transcribed spacer 2, which is highly conserved in 25 Colletotrichum species in GenBank. Our results indicated that the LAMP assay, which uses template DNA prepared using microwave irradiation, is a simple and sensitive tool for detecting C. gloeosporioides in infected strawberry plants. Further, our results showed that the LAMP assay could differentiate Colletotrichum species such as C. acutatum, C. aenigma, and C. siamense. [ABSTRACT FROM AUTHOR]

Neutral electrolyzed water (NEW: pH 6.5-7.5) applied through an overhead irrigation system was evaluated for control of strawberry anthracnose caused by Colletotrichum fructicola. Conidia of the pathogen were completely killed by a 10-s exposure to 10.0 mg/L of available chlorine in the NEW. Disease suppression was significantly higher using the NEW treatment through overhead irrigation, either alone or combined with fungicides, than using conventional fungicides. Plants had no visible phytotoxicity after the NEW treatment, even when combined with fungicides. Thus, the NEW treatment was effective at controlling anthracnose caused by C. fructicola. [ABSTRACT FROM AUTHOR]

In order to know the pathogenesis of Colletotrichum fragariae and the interaction mechanism with the hosts at levels of histology and cytology, the healthy strawberry seedlings were inoculated with conidia of pathogen C. fragariae by root dipping in conidia suspension. The pathogen infection process was observed by fluorescence microscope at different time points after inoculation. Results： After 12 h, 95 % of conidia germinated, about 69 % conidia formed classical appressoria and hyphopodia, and infection pegs began to penetrate the epidermal cells of roots at 24 h, and by 48 h, the hyphae had extensively colonized and formed a network around the roots. By four days, several plants had developed slightly brown discolouration at root tips, by nine days, almost all roots had developed largely black and/or brown discolouration and formed a spot of acervulus. By 13 days, hyphae had invaded to the vascular bundle on the main roots and formed the new conidia, completing the disease cycle. By 20 days, hyphae had invaded petioles and rachis above ground, and were found on the petioles surface and glandular hairs of petioles at 41 d. By 55 d hyphae had invaded the leaves and their glandular hairs. Typical anthracnose disease spots were found on the leaves, which had begun to decompose. Conclusion： subsequent to inoculation, the C. fragariae infection can spread across the entire strawberry plants via the roots, which is indicative of a systemic infection. [ABSTRACT FROM AUTHOR]

To investigate the pathogen of strawberry anthracnose and the antibacterial activity of different fungicides on strawberry anthracnose, the morphologic traits, pathogenicity and molecular identification for the pathogen of strawberry anthracnose collected in Jurong city, Jiangsu province were studied, and then the indoor toxicity of 12 different fungicides on strawberry anthracnose by using mycelium growth rate method were determined. The results showed that the pathogen was Gl-omerella cingulata. According to the indoor tests, the EC50 values of Prochloraz, Flusilazole, Pro-piconazole, Epoxiconazole, Difenoconazole, Tebuconazole, Diniconazole, Pyraclostrobin, Hexaconazole, Myclobutanil, Carbendazim and Boscalid were 0. 0544, 0. 4220, 0. 6831, 0. 7112, 0. 8083, 1. 2652, 1. 3560, 1. 9176, 2. 2559, 7. 5834, 14. 3522 and16. 8140 μg · mL-1, respectively. There was great difference between the sensitivity of strawberry anthracnose to 12 different fungicides, among them strawberry anthracnose was the most sensitive to Prochloraz. [ABSTRACT FROM AUTHOR]

The composition of non-infected and Colletotrichum nymphaeae infected strawberry fruits (cultivar ‘Asia') in three different stages of ripeness were evaluated. Additionally, the effect of infection on strawberry runners was monitored. C. nymphaeae infection caused a significant increase in total sugar content in mature fruits (1.1 fold) and a decrease in total sugar content in semi-mature fruits (1.4 fold) and organic acid content in all stages of ripeness (1.7 fold). Ellagic acid derivatives (1.9 fold), flavanols (1.5 fold) and flavonols (5.1 fold) significantly increased during all stages of ripeness after infection. The pattern of phenolic accumulation in strawberry runners was altered by C. nymphaeae infection in contrast to strawberry fruits as most of identified phenols decreased as a response to the infection. [ABSTRACT FROM AUTHOR]

15 soil samples were collected, and 79 actinomycetes strains were isolated by dilution plate method. 5 strains with antagonistic effects on Colletotrichum gloeosporioides were obtained by plate confrontation and growth rate methods. The antagonistic rate of strain DTJ-24 was as high as 69. 89 %,and had good passage stability. Based on the morphological, biochemical characteristics and 16s rDNA gene sequence analysis,the strain DTJ-24 was identified as Streptomyces lavendulae. It is the first time to report that S. lavendulae have antagonistic effects on strawberry anthracnose. [ABSTRACT FROM AUTHOR]

Microscopic investigations were conducted into the interaction of Colletotrichum acutatum on white and red strawberry (Fragaria ・ananassa) fruit surfaces. The results showed that, whilst the early interaction events were similar in both white and red fruits, after 24 h fungal colonization dramatically varied: in white fruits C. acutatum became quiescent as melanized appressoria, but on red fruits it displayed subcuticular necrotrophic invasion. A microarray analysis of white and red strawberries after 24 h of interaction with C. acutatum was performed, in order to reveal differences in gene expression possibly related to the different susceptibility of unripe and ripe fruits. Epi ⁄ catechin related genes and fatty acid metabolism genes, involved in the production of quiescence-related molecules such as flavan-3-ols, proanthocyanidins and antifungal dienes, were found to be regulated during strawberry ripening, supporting a role for these molecules as preformed defence mechanisms. Besides several genes commonly regulated upon pathogen interaction, different genes were specifically transcribed only in white or red challenged fruits; a number of these, such as those coding for lectin and polyphenol oxidase, possibly account for specific pathogen-induced responses. The putative biological role of these genes in the different susceptibility of fruits to C. acutatum is discussed. [ABSTRACT FROM AUTHOR]

To analyze genetic relationships among Colletotrichum gloeosporioides isolates; 34 isolates were collected from strawberries all over Japan, but primarily from Chiba Prefecture, and 20 were isolated from hosts other than strawberry. These isolates were assayed for virulence on strawberries and subjected to a fingerprint (FP) analysis by repetitive extragenic palindromic-PCR. Most of the isolates that were highly virulent to strawberries had relatively similar FPs even though they were isolated from various host plants (strawberry, cyclamen, nipplefruit and Japanese pear) in different regions. A cluster analysis revealed that the highly virulent and the weakly virulent isolates tended to form individual clusters, indicating that the highly virulent strains of C. gloeosporioides, which were genetically close to isolates with similar FPs and distinguishable from the weakly virulent strains, were responsible for strawberry anthracnose in Japan. [ABSTRACT FROM AUTHOR]

The effects of a range of concentrations of four nutrients – nitrogen, phosphorus, potassium and calcium – in fertilizer solutions on the severity of anthracnose on strawberry cv. Nyoho cultivated under a noncirculation hydroponics system were determined after inoculation with Colletotrichum gloeosporioides. Crop growth and tissue nitrogen, phosphorus, potassium and calcium contents of the entire above-ground parts of the plant were also investigated. Elevated nitrogen and potassium concentrations in the fertilizer solution increased disease severity in contrast to phosphorus and calcium. Treatment with either NH4 or NO3 nitrogen was not significantly different. The dry weight of the strawberry plants increased significantly with elevated concentrations of nitrogen ( R2 = 0·9078) and phosphorus ( R2 = 0·8842), but was not influenced by the elevated amounts of potassium ( R2 = 0·8587) and calcium ( R2 = 0·6526) concentrations. [ABSTRACT FROM AUTHOR]

Abstract Isolates of Colletotrichum acutatum , C. fragariae and C. gloeosporioides pathogenic to strawberry plants were examined by sequence analysis of the 5.8S-ITS region. Phylogenetic relationships among isolates of Colletotrichum are, for the most part, congruent with the molecular groups established in earlier works. 5.8S-ITS sequence analysis showed a high level of genetic divergence within C. acutatum. Isolates of this species clustered into two very distinct clusters with further subdivision. The divergences between C. fragariae and C. gloeosporioides were too low to distinguish them as separate species. On the basis of the sequence data, specific primers were designed both to identify isolates belonging to the genus Colletotrichum , and to distinguish isolates of the species C. acutatum . The specificity of these primers was validated by testing a wide range of strawberry isolates of Colletotrichum , non-strawberry isolates of Colletotrichum and other fungi used as controls. Although the 5.8S-ITS sequences were not polymorphic enough to allow the construction of C. gloeosporioides -specific primers, specific PCR amplification followed by an Mvn I digestion provides a tool to specifically identify strawberry isolates of C. gloeosporioides . [ABSTRACT FROM AUTHOR]

Abstract Strains of Colletotrichum species isolated from diseased strawberry plants from different countries were studied by random amplified polymorphic DNA (RAPD). Grouping and variability shown by RAPD supported the results of previous molecular studies made of Colletotrichum species. The variability was larger with C. acutatum , in which 15 different RAPD patterns were observed. Cluster analysis (UPGMA) was used to divide the C. acutatum strains into two major groups that correlated with other molecular markers previously used. Strains belonging to the first group showed a high level of similarity despite their diverse geographical origins, which probably correspond to a clonal population that resulted from a rapid and wide expansion of the strawberry trade. On the contrary, strains belonging to the second group showed a high level of genetic diversity that could indicate that they belong to lineages of older origins and/or to sexual reproducing lines. Within C. fragariae and C. gloeosporioides , two morphologically indistinguishable species, less genetic variability was observed, but both species were differentiated by RAPD patterns. A C. fragariae associated RAPD band was cloned, sequenced and used to design specific primers for this species. A PCR product of 580 bp was obtained only when DNA from C. fragariae strains was used, and this is proposed as a method for quickly and easily identifying C. fragariae strains. [ABSTRACT FROM AUTHOR]

Strawberry anthracnose, caused by Colletotrichum species, is a major fungal disease threatening the strawberry industry in Sichuan Province of southwestern China. However, research on identification of Colletotrichum species associated with strawberry anthracnose in Sichuan remains scarce. In this study, 73 representative Colletotrichum strains were isolated from diseased leaves, stolons, petioles, and crowns of 11 major strawberry-planting localities in Sichuan Province. Based on morphological characteristics and multiloci phylogenetic analysis, the Colletotrichum strains were identified as three distinct species: Colletotrichum fructicola (53 strains, 72.60%), Colletotrichum siamense (17 strains, 23.29%), and Colletotrichum gloeosporioides sensu stricto (3 strains, 4.11%). Among them, C. fructicola was the most ubiquitous and dominant species, whereas C. gloeosporioides sensu stricto was restricted to Chongzhou. Importantly, our pathogenicity tests showed that C. fructicola and C. siamense can infect both leaves and stolons, whereas C. gloeosporioides sensu stricto was only pathogenic to leaves. Interestingly, although the sexual stage of C. siamense was not observed in this study, it still exhibited the strongest virulence to strawberry compared with C. gloeosporioides sensu stricto and C. fructicola . This is the first study to characterize Colletotrichum species causing strawberry anthracnose and evaluate their pathogenicity in Sichuan Province of southwestern China, which will provide a better strategy for accurate diagnosis and management of anthracnose disease in strawberry.

Modern strawberry production is often threatened by microbe pathogens. Anthracnose is among the most prominent fungal disease caused mainly by Colletotrichum gloeosporioides and leads to large-scale losses both in quality and yield. Little is known regarding the mechanisms underlying the genetics in the strawberry- C. gloeosporioides interaction. In the current research, a wild accession ' Fragaria nilgerrensis ' is used as a resistant model to study the roles of terpenoid and terpene genes in leaf response to C. gloeosporioides. We found that several terpenoids and terpene genes were up-regulated at early time points after challenged with C. gloeosporioides. Among the metabolites detected, sesquiterpenes were the most significantly accumulated compounds, increasing up to ~12-fold at 18 h post infection (hpi), followed by monoterpenes which showed a slight increase upon infection. Consistently, the time-resolved transcriptome data revealed that genes pertaining to terpenoid metabolism were rapidly up-regulated and co-expressed with signaling pathway genes relevant to defense response. Notably, quantitative real-time PCR confirmed that the expression of five terpene synthase genes (TPS) were greatly enhanced, by a factor of one to three orders of magnitude at 3–6 hpi. Our results reveal a possible link between rapidly induced terpenoid metabolism and the autoimmunity underlying anthracnose resistance in a wild strawberry species. Image 1 • The wild strawberry Fragaria nilgerrensis is resistant to C. gloeosporioides , a causal agent of anthracnose disease. • Spray treatment of leaves with fungal spores induces rapid reprogramming in leaf metobolomics and transcriptome. • Rapid accumulation of terpenoids, particularly sesquiterpene compounds in challenged leaves is observed. • Genes encoding the MVA and MEP pathways as well as four terpene synthases are up-regulated at early as 3-6 hpi. • Terpenoid biosynthesis genes are co-expressed with genes of the host defense pathways. [ABSTRACT FROM AUTHOR]

Multiple species in the fungal genus Colletotrichum cause anthracnose fruit rot diseases that are responsible for major yield losses of as much as 100%. Individual species of Colletotrichum typically have broad host ranges and can infect multiple fruit species. Colletotrichum fioriniae causes anthracnose fruit rots of apples, blueberries, and strawberries in Kentucky orchards where these fruits grow in close proximity. This raises the possibility of cross-infection, which may have significant management implications. The potential occurrence of cross-infection was investigated by using telomere fingerprinting to identify C. fioriniae clones in several mixed-fruit orchards. Telomere fingerprints were highly polymorphic among a test group of C. fioriniae strains and effectively defined clonal lineages. Fingerprints were compared among apple, blueberry, and strawberry isolates of C. fioriniae from three different orchards and similarity matrices were calculated to build phylograms for each orchard group. Multiple clonal lineages of C. fioriniae were identified within each orchard on the same fruit host. Related lineages were found among isolates from different hosts, but the results did not provide direct evidence for cross-infection of different fruit species by the same clones. Recovery of the same clonal lineages within orchards across multiple years suggested that local dispersal was important in pathogen population structure and that C. fioriniae strains persisted within orchards over time. Isolates from blueberry were less diverse than isolates from apple, perhaps related to more intensive anthracnose management protocols on apple versus blueberry. Telomere fingerprinting is a valuable tool for understanding population dynamics of Colletotrichum fruit rot fungi.

• Nano-encapsulation is a promising strategy to the applicability of essential oils as antimicrobials. • Essential oils from thyme and dill took longer to be released when they were encapsulated in silver nanoparticles. • Thyme and dill essential oils encapsulated silver nanoparticles had higher antifungal effect. • Nano-encapsulation changed essential oils composition and fungal morphology. Nanotechnology is an eco-friendly strategy in managing plant diseases. In combination with existing practices nanotechnology can enhance the protection of agricultural products and food. For example, essential oils (EOs) of thyme (Thymus daenensis L.) and dill (Anethum graveolens L.) have an antimicrobial potential and this potential may be enhanced by certain nanoparticle systems. Here we demonstrate that encapsulating EOs of thyme and dill in silver nanoparticles increases their fungicidal activity against Colletotrichum nymphaeae , causing anthracnose in many horticultural crops. Using GC-MS analysis, we identified p -cymene, thymol, carvacrol and (E)-caryophyllene as the main EOs of thyme and limonene, cis -dihydrocarvone, cyclohexanon, and carvone as the main EOs of dill. When the EOs of the two sources were encapsulated in silver nanoparticles, synergistic effects against C. nymphaeae were observed, resulting in more than 80% inhibition of mycelium growth of C. nymphaeae. Moreover, conidia germination was suppressed by nano-encapsulated EOs. We also observed considerable morphological changes in the fungal hyphae when nano-encapsulated EOs were applied. Our study demonstrates the potential of encapsulated EOs in controlling pathogens that can be very applicable as antifungal agents. [ABSTRACT FROM AUTHOR]

Fungi in the genus Colletotrichum cause apple, blueberry, and strawberry fruit rots, which can result in significant losses. Accurate identification is important because species differ in aggressiveness, fungicide sensitivity, and other factors affecting management. Multiple Colletotrichum species can cause similar symptoms on the same host, and more than one fruit type can be infected by a single Colletotrichum species. Mixed-fruit orchards may facilitate cross-infection, with significant management implications. Colletotrichum isolates from small fruits in Kentucky orchards were characterized and compared with apple isolates via a combination of morphotyping, sequencing of voucher loci and whole genomes, and cross-inoculation assays. Seven morphotypes representing two species complexes ( C. acutatum and C. gloeosporioides ) were identified. Morphotypes corresponded with phylogenetic species C. fioriniae , C. fructicola , C. nymphaeae , and C. siamense , identified by TUB2 or GAPDH barcodes. Phylogenetic trees built from nine single-gene sequences matched barcoding results with one exception, later determined to belong to an undescribed species. Comparison of single-gene trees with representative whole genome sequences revealed that CHS and ApMat were the most informative for diagnosis of fruit rot species and individual morphotypes within the C. acutatum or C. gloeosporioides complexes, respectively. All blueberry isolates belonged to C. fioriniae , and most strawberry isolates were C. nymphaeae , with a few C. siamense and C. fioriniae also recovered. All three species cause fruit rot on apples in Kentucky. Cross-inoculation assays on detached apple, blueberry, and strawberry fruits showed that all species were pathogenic on all three hosts but with species-specific differences in aggressiveness.

Anthracnose is a serious fungal disease that primarily infects strawberry roots and stolons during development. Here, 91 isolates from different areas of Zhejiang province, China, were collected. Morphological characteristics were analyzed, and a phylogenetic analysis based on multiple genes (actin, internal transcribed spacer, calmodulin, glyceraldehyde-3-phosphate dehydrogenase, and chitin synthase) was performed. We found that all of the Colletotrichum species causing strawberry anthracnose belonged to the Colletotrichum gloeosporioides complex. Among them, we identified 48 isolates of C. fructicola , 21 isolates of C. siamense , 13 isolates of C. gloeosporioides , and 9 isolates of C. aenigma . C. siamense was distributed in the central and eastern regions of Zhejiang province (Hangzhou, Jinhua, Shaoxing, Ningbo, and Taizhou). This is the first report of C. siamense causing strawberry anthracnose in Zhejiang province. C. fructicola was the most dominant species causing strawberry anthracnose in Zhejiang province. We identified the four species causing strawberry anthracnose in Zhejiang province, which will improve our understanding of the strawberry anthracnose epidemic and will benefit the development of future control measures.

To prevent the spread of anthracnose in strawberry plants and characterize the metabolic changes occurring during plant-pathogen interactions, we developed a method for the early diagnosis of disease based on an analysis of the metabolome by gas chromatography-mass spectrometry. An examination of the metabolic profile revealed 189 and 202 total ion chromatogram peaks for the control and inoculated plants, respectively. A partial least squares discriminant analysis (PLS-DA) model was conducted for the reliable and accurate discrimination between healthy and diseased strawberry plants, even in the absence of disease symptoms (e.g., early stages of infection). ANOVA (analysis of variance) and orthogonal partial least squares analysis (OPLS) identified 20 metabolites as tentative biomarkers of Colletotrichum theobromicola infection (e.g., citric acid, d-xylose, erythrose, galactose, gallic acid, malic acid, methyl α-galactopyranoside, phosphate, and shikimic acid). At least some of these potential biomarkers may be applicable for the early diagnosis of anthracnose in strawberry plants. Moreover, these metabolites may be useful for characterizing pathogen infections and plant defense responses. This study confirms the utility of metabolomics research for developing diagnostic tools and clarifying the mechanism underlying plant-pathogen interactions. Furthermore, the data presented herein may be relevant for developing new methods for preventing anthracnose in strawberry seedlings cultivated under field conditions.