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The Plant Pathology Journal Aug 2018Northern corn leaf spot and southern corn leaf blight caused by (anamorph, ) and (anamorph, ), respectively, are common maize diseases in Korea. Accurate detection of...
Northern corn leaf spot and southern corn leaf blight caused by (anamorph, ) and (anamorph, ), respectively, are common maize diseases in Korea. Accurate detection of plant pathogens is necessary for effective disease management. Based on the polyketide synthase gene (PKS) of and the nonribosomal peptide synthetase gene (NRPS) of , primer pairs were designed for PCR to simultaneously detect the two fungal pathogens and were specific and sensitive enough to be used for duplex PCR analysis. This duplex PCR-based method was found to be effective for diagnosing simultaneous infections from the two species that display similar morphological and mycological characteristics. With this method, it is possible to prevent infections in maize by detecting infected seeds or maize and discarding them. Besides saving time and effort, early diagnosis can help to prevent infections, establish comprehensive management systems, and secure healthy seeds.
PubMed: 30140186
DOI: 10.5423/PPJ.FT.10.2017.0209 -
Frontiers in Plant Science 2021Spot blotch (SB) of wheat is emerging as a major threat to successful wheat production in warm and humid areas of the world. SB, also called leaf blight, is caused by ,...
Spot blotch (SB) of wheat is emerging as a major threat to successful wheat production in warm and humid areas of the world. SB, also called leaf blight, is caused by , and is responsible for high yield losses in Eastern Gangetic Plains Zone in India. More recently, SB is extending gradually toward cooler, traditional wheat-growing North-Western part of the country which is a major contributor to the national cereal basket. Deployment of resistant cultivars is considered as the most economical and ecologically sound measure to avoid losses due to this disease. In the present study, 89 backcross introgression lines (DSBILs) derived from (cv. PDW274-susceptible) × (resistant) were evaluated against SB for four consecutive years, 2016-2020. Phenotypic evaluation of these lines showed a continuous variation in disease severity indicating that the resistance to SB is certainly quantitative in nature. Phenotypic data of DSBILs were further used for mapping QTLs using SNPs obtained by genotyping by sequencing. To identify QTLs stable across the environments, Best Linear Unbiased Estimates (BLUEs) and Predictions (BLUPs) were used for mapping QTLs based on stepwise regression-based Likelihood Ratio Test (RSTEP-LRT) for additive effect of markers and single marker analysis (SMA). Five QTLs, , , , , and , linked to SB resistance were mapped across chromosomes 2A, 2B, 3B, 5B, and 6A. Genes found adjacent to the SNP markers linked to these QTLs were literature mined to identify possible candidate genes by studying their role in plant pathogenesis. Further, highly resistant DSBIL (DSBIL-13) was selected to cross with a susceptible hexaploidy cultivar (HD3086) generating BCF population. The QTL , linked to SNP S5B_703858864, was validated on this BCF population and thus, may prove to be a potential diagnostic marker for SB resistance.
PubMed: 34122476
DOI: 10.3389/fpls.2021.650400 -
Plants (Basel, Switzerland) Mar 2023Southern corn leaf blight (SCLB) caused by threatens maize growth and yield worldwide. In this study, TMT-labeled comparative peptidomic analysis was established...
Southern corn leaf blight (SCLB) caused by threatens maize growth and yield worldwide. In this study, TMT-labeled comparative peptidomic analysis was established between infected and uninfected maize leaf samples using liquid-chromatography-coupled tandem mass spectrometry. The results were further compared and integrated with transcriptome data under the same experimental conditions. Plant peptidomic analysis identified 455 and 502 differentially expressed peptides (DEPs) in infected maize leaves on day 1 and day 5, respectively. A total of 262 common DEPs were identified in both cases. Bioinformatic analysis indicated that the precursor proteins of DEPs are associated with many pathways generated by SCLB-induced pathological changes. The expression profiles of plant peptides and genes in maize plants were considerably altered after infection. These findings provide new insights into the molecular mechanisms of SCLB pathogenesis and offer a basis for the development of maize genotypes with SCLB resistance.
PubMed: 36986996
DOI: 10.3390/plants12061307 -
Frontiers in Plant Science 2018Spot blotch (SB) caused by (anamorph: ) is an economically important disease of wheat worldwide. Under a severe epidemic condition, the disease can cause yield losses...
Spot blotch (SB) caused by (anamorph: ) is an economically important disease of wheat worldwide. Under a severe epidemic condition, the disease can cause yield losses up to 70%. Previous approaches like bi-parental mapping for identifying SB resistant genes/QTLs exploited only a limited portion of the available genetic diversity with a lower capacity to detect polygenic traits, and had a lower marker density. In this study, we performed genome-wide association study (GWAS) for SB resistance in hard winter wheat association mapping panel (HWWAMP) of 294 genotypes. The HWWAMP was evaluated for response to (isolate SD40), and a range of reactions was observed with 10 resistant, 38 moderately resistant, 120 moderately resistant- moderately susceptible, 111 moderately susceptible, and 15 susceptible genotypes. GWAS using 15,590 high-quality SNPs and 294 genotypes we identified six QTLs ( = <0.001) on chromosomes 2D, 3A, 4A, 4B, 5A, and 7B that collectively explained 30% of the total variation for SB resistance. Highly associated SNPs were identified for all six QTLs, (SNP: Kukri_c31121_1460, = 4%), (SNP: Excalibur_c46082_440, = 4%), 1 (SNP: IWA8475, = 5.5%), (SNP: Excalibur_rep_c79414_306, = 4%), (SNP: Kukri_rep_c104877_2166, = 6%), and (SNP: TA005844-0160, = 6%). Our study not only validates three (2D, 5A, and 7B) genomic regions identified in previous studies but also provides highly associated SNP markers for marker assisted selection. In addition, we identified three novel QTLs (, 1, and ) for SB resistance in wheat. Gene annotation analysis of the candidate regions identified nine NBS-LRR and 38 other plant defense-related protein families across multiple QTLs, and these could be used for fine mapping and further characterization of SB resistance in wheat. Comparative analysis with barley indicated the SB resistance locus on wheat chromosomes 2D, 3A, 5A, and 7B identified in our study are syntenic to the previously identified SB resistance locus on chromosomes 2H, 3H, 5H, and 7H in barley. The 10 highly resistant genotypes and SNP markers identified in our study could be very useful resources for breeding of SB resistance in wheat.
PubMed: 30034404
DOI: 10.3389/fpls.2018.00926 -
Journal of Applied Microbiology Oct 2017This study aimed at evaluating the inhibitory effects of various organic extracts of Ocimum basilicum against some species of Bipolaris and Cochliobolus with GC-MS and...
AIMS
This study aimed at evaluating the inhibitory effects of various organic extracts of Ocimum basilicum against some species of Bipolaris and Cochliobolus with GC-MS and HPLC analysis.
METHODS AND RESULTS
The ethyl acetate extract consisted of methyl cinnamate as the most abundant component, while butylated hydroxytoluene was the major component in the methanol extract. Pyrogallol and chlorogenic acid were major phenolic compounds in the ethyl acetate and methanol extracts, respectively. Complete growth inhibition of all fungi except Cochliobolus australiensis was observed by ethyl acetate extract, and on Bipolaris hawaiensis, Bipolaris spicifera and Cochliobolus cynodontis by methanol extract. Spore germination was completely inhibited for Bipolaris hawaiensis by ethyl acetate extract. Scanning electron microscopic observations revealed that the organic extracts cause considerable morphological changes of the fungal hyphae such as mycelial asymmetry, hyphal swelling, sunken, curling, distorted and broken hyphae.
CONCLUSIONS
The ethyl acetate and methanol extracts of O. basilicum can result in an effective suppression of mycelial growth, spore germination and germ tube elongation of Bipolaris and Cochliobolus species.
SIGNIFICANCE AND IMPACT OF THE STUDY
The organic extracts of O. basilicum are potential and promising natural tools for controlling Bipolaris and Cochliobolus species, economically important plant and human fungal pathogens.
Topics: Antifungal Agents; Ascomycota; Humans; Morphogenesis; Ocimum basilicum; Plant Extracts; Spores, Fungal
PubMed: 28718990
DOI: 10.1111/jam.13543 -
Journal of Fungi (Basel, Switzerland) Apr 2022Kazakhstan is the fourteenth largest wheat producer in the world. Despite this fact, there has not been a comprehensive survey of wheat root and crown rot. A...
Kazakhstan is the fourteenth largest wheat producer in the world. Despite this fact, there has not been a comprehensive survey of wheat root and crown rot. A quantitative survey was conducted for the purpose of establishing the distribution of fungi associated with root and crown rot on wheat (Triticum spp.). During the 2019 growing season, samples were taken from the affected plants’ roots and stem bases. A total of 1221 fungal isolates were acquired from 65 sites across the central (Karagandy region), eastern (East Kazakhstan region), and southeastern (Almaty region) parts of the country and identified using morphological and molecular tools. The internal transcribed spacer (ITS), translation elongation factor 1-alpha (EF1-α), and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) sequences were successfully used to identify the species of fungal isolates. It was found that Bipolaris sorokiniana (44.80%) and Fusarium acuminatum (20.39%) were the most predominant fungal species isolated, which were present in 86.15 and 66.15% of the fields surveyed, respectively, followed by F. equiseti (10.16%), Curvularia spicifera (7.62%), F. culmorum (4.75%), F. oxysporum (4.10%), F. redolens (2.38%), Rhizoctonia solani AG2-1 (1.06%), Nigrospora oryzae (0.98%), C. inaequalis (0.90%), F. pseudograminearum (0.74%), F. flocciferum (0.74%), Macrophomina phaseolina (0.66%), F. cf. incarnatum (0.33%), Fusarium sp. (0.25%), and F. torulosum (0.16%). A total of 74 isolates representing 16 species were tested via inoculation tests on the susceptible Triticum aestivum cv. Seri 82 and the results revealed that F. culmorum and F. pseudograminearum, B. sorokiniana, Fusarium sp., R. solani, F. redolens, C. spicifera, C. inaequalis, and N. oryzae were virulent, whereas others were non-pathogenic. The findings of this investigation demonstrate the presence of a diverse spectrum of pathogenic fungal species relevant to wheat crown and root rot in Kazakhstan. To the best of our knowledge, this is the first report of F. pseudograminearum, Fusarium sp., C. spicifera, and C. inaequalis as pathogens on wheat in Kazakhstan.
PubMed: 35628673
DOI: 10.3390/jof8050417 -
3 Biotech Oct 2022Brown spot disease, caused by , is one of the several disastrous diseases affecting rice. The brown spot fungus illustrates substantial pathogenic and genetic...
UNLABELLED
Brown spot disease, caused by , is one of the several disastrous diseases affecting rice. The brown spot fungus illustrates substantial pathogenic and genetic variability. To the best of our knowledge, extensive analysis utilizing specific SSR primers for genome is quite inadequate for the population structure and genetic diversity of Indian isolates. A total of 84 brown spot isolates were collected from rice-cultivating areas across southern and eastern Indian states, viz., Tamil Nadu, Andhra Pradesh, Odisha and Chhattisgarh. The pathogenicity and virulence characteristics of these isolates were assessed with the susceptible cultivar CR Dhan 201. Twelve genome-specific SSR markers of warranted the investigation of the population structure and genetic diversity among the isolates. These isolates were categorized based on their disease grade as highly virulent isolates (4 nos.), virulent isolates (8 nos.), moderately virulent isolates (47 nos.) and less virulent isolates (25 nos.). PCR amplification and DNA sequencing confirmed the isolates to be PCR amplification and DNA sequencing confirmed the isolates to be The SSR markers produced a total of 35 alleles with 1 to 4 alleles per locus with a gene diversity ranging between 0.00 and 0.687 and a major allele frequency variation of 0.425-0.975. The PIC value ranged from 0.00 to 0.638 having a mean value of 0.34. Cluster analysis technique was applied to group the brown spot isolates into four distinct clusters. Principal coordinate and structure analysis identified two genetic clusters of isolates for individual states with some degree of distinctness complying with their virulence. Analysis of molecular variance revealed more genetic variation within populations and less among populations. The study outcome would expedite the comprehension of genetic diversity of across the southern and eastern states of India. Furthermore, we anticipate its guidance in the development of more effective disease management strategies as well as in the generation of novel resistant varieties through marker-assisted breeding.
SUPPLEMENTARY INFORMATION
The online version contains supplementary material available at 10.1007/s13205-022-03347-4.
PubMed: 36275360
DOI: 10.1007/s13205-022-03347-4 -
Persoonia Dec 2014The fungal genus Curvularia includes numerous plant pathogens and some emerging opportunistic pathogens of humans. In a previous study we used morphology and sequences...
The fungal genus Curvularia includes numerous plant pathogens and some emerging opportunistic pathogens of humans. In a previous study we used morphology and sequences of the nuclear ribosomal internal transcribed spacer region (ITS) and the glyceraldehyde-3-phosphate dehydrogenase (gpd) gene to identify species within a set of 99 clinical Curvularia isolates from the USA. Seventy-two isolates could be identified while the remaining 27 isolates belonged in three unclassified clades that were tentatively labelled Curvularia sp. I, II and III. In the present study, we further assess the taxonomic placement of these isolates using sequences of ITS, gpd, the large subunit rDNA, and the second largest subunit of RNA polymerase II. DNA sequence comparisons with a set of 87 isolates representing 33 Curvularia spp. and members of the closely-related genera Bipolaris and Exserohilum revealed that Curvularia sp. I, II and III represent novel lineages in Curvularia. These lineages are morphologically different from the currently accepted species. In the phylogenetic tree, Curvularia sp. I and sp. III were each split into two distinct lineages. Morphology and phylogeny supported the proposal of five new species, to be named C. americana, C. chlamydospora, C. hominis, C. muehlenbeckiae and C. pseudolunata. The concatenated 4-locus phylogeny revealed the existence of six clades in Curvularia, which are associated with particular morphological features. They were named after representative species, namely americana, eragrostidis, hominis, lunata, spicifera and trifolii.
PubMed: 25737593
DOI: 10.3767/003158514X683538 -
Journal of Fungi (Basel, Switzerland) Jan 2022Spot blotch caused by is a destructive disease of wheat worldwide. This study investigated the aggressiveness of isolates from different wheat-growing areas of Bolu...
Spot blotch caused by is a destructive disease of wheat worldwide. This study investigated the aggressiveness of isolates from different wheat-growing areas of Bolu province in Turkey on the cultivar Seri-82. Host susceptibility of 55 wheat cultivars was evaluated against the most aggressive isolate. Our results indicated that the cultivars Anafarta and Koç-2015 were the most resistant. A specific and sensitive qPCR assay was developed for detecting the pathogen in plant tissues and evaluating wheat plants with different resistance levels. Three primer sets, BsGAPDHF/BsGAPDHR, BsITSF/BsITSR, and BsSSUF/BsSSUR, were designed based on glyceraldehyde-3-phosphate dehydrogenase, internal transcribed spacers, and 18S rRNA loci of with detection limits of 1, 0.1, and 0.1 pg of pathogen DNA, respectively. The qPCR assay was highly sensitive and did not amplify DNA from the other closely related fungal species and host plants. The protocol differentiated wheat plants with varying degrees of resistance. The assay developed a useful tool for the quantification of the pathogen in the early stages of infection and may provide a significant contribution to a more efficient selection of wheat genotypes in breeding studies. In the present study, expression levels of PR proteins, phenylalanine ammonia-lyase, catalase, ascorbate peroxidase, and superoxide dismutase enzymes were upregulated in Anafarta (resistant) and Nenehatun (susceptible) cultivars at different post-infection time points, but more induced in the susceptible cultivar. The results showed considerable variation in the expression levels and timing of defense genes in both cultivars.
PubMed: 35205903
DOI: 10.3390/jof8020149 -
PloS One 2021The current study involves the biogenesis of titanium dioxide nanoparticles (TiO2 NPs) by using Moringa oleifera Lam. aqueous leaf extract for the reduction of titanium...
The current study involves the biogenesis of titanium dioxide nanoparticles (TiO2 NPs) by using Moringa oleifera Lam. aqueous leaf extract for the reduction of titanium dioxide salt into TiO2 nanoparticles. The biosynthesized TiO2 nanoparticles were observed by using the UV-visible spectrophotometry, SEM, EDX and XRD analytical methods. It was confirmed that the nanoparticles are crystalline and exist in the size range of 10-100 nm. The FTIR analysis confirmed the presence of O-H (hydrogen bonding), N-H (amide), C-C (alkanes) and C-I (Iodo-stretch) functional groups responsible for the stabilization of nanoparticles. Various concentrations (20, 40, 60 and 80 mg/L) of TiO2 NPs were applied exogenously on wheat plants infected with a fungus Bipolaris sorokiniana responsible to cause spot blotch disease at different time intervals. The measurement of disease incidence and percent disease index showed the time-dependent response and 40 mg/L was reported a stable concentration of TiO2 NPs to reduce the disease severity. The effects of biosynthesized TiO2 NPs were also evaluated for agro-morphological (leaf and root surface area, plant fresh and dry weight and yield parameters), physiological (relative water content, membrane stability index and chlorophyll content) and non-enzymatic metabolites (soluble sugar, protein, soluble phenol and flavonoid content) in wheat plants under biotic stress and 40 mg/L concentration of TiO2 NPs was found to be effective to elicit modifications to reduce biotic stress. The current study highlights the significant role of biosynthesized TiO2 NPs in controlling fungal diseases of wheat plants and thus ultimately improving the quality and yield of wheat plants.
Topics: Bipolaris; Chemical Phenomena; Nanoparticles; Pest Control, Biological; Plant Diseases; Spectroscopy, Fourier Transform Infrared; Stress, Physiological; Titanium; Triticum
PubMed: 33571310
DOI: 10.1371/journal.pone.0246880