Plant Pathogen Research Papers - Academia.edu (original) (raw)

2025, Current trends in Bioinformatics: An Insight

2025

Los polinizadores son necesarios para producir semillas de cebolla. Esta especie es uno de los principales cultivos hortícolas. Dos tipos de variedades de cebolla se cultivan principalmente en todo el mundo: híbridos y cultivares de polinización abierta (PA). Aunque los híbridos ofrecen ventajas a los cultivadores de bulbos, los rendimientos de semillas de los híbridos son más bajos que los cultivares PA y eso es un problema importante. Se determinó la influencia de los factores ambientales (temperatura, radiación, precipitación, humedad relativa (HR) y velocidad del viento), así como la atracción de abejas y la producción de semillas en tres localidades, de principal zona productora de semillas de cebolla en Argentina. Se utilizaron nueve líneas androestériles (LAE) y una PA. Los resultados obtenidos mostraron una marcada variabilidad en la atracción de abejas y la producción de semillas entre la variedad PA y las LAE y dentro de las LAE. Además, los factores ambientales, como la t...

2025, Journal of Labelled Compounds and Radiopharmaceuticals

The MMPI [ 14 C]ABT-770 (1), N-[(1S)-1- [(4,4-Dimethyl-2,5- ethyl]-Nhydroxyformamide was synthesized in 8 steps using 4-bromophenol-UL-14 C (10) as a starting material. The Carbon-14 label was introduced in one of the metabolically stable biphenyl rings. The key sequence of the synthesis was a three-step one-pot reaction in which the hydantoin moiety was introduced, the imine oxidized and further hydrolyzed to get the penultimate precursor to [ 14 C]ABT-770 (1) in 56% yield.

2025, Journal of Virology

Tomato spotted wilt virus (TSWV), a member of the Tospovirus genus within the Bunyaviridae , is an economically important plant pathogen with a worldwide distribution. TSWV is transmitted to plants via thrips (Thysanoptera: Thripidae), which transmit the virus in a persistent propagative manner. The envelope glycoproteins, G N and G C , are critical for the infection of thrips, but they are not required for the initial infection of plants. Thus, it is assumed that the envelope glycoproteins play important roles in the entry of TSWV into the insect midgut, the first site of infection. To directly test the hypothesis that G N plays a role in TSWV acquisition by thrips, we expressed and purified a soluble, recombinant form of the G N protein (G N -S). The expression of G N -S allowed us to examine the function of G N in the absence of other viral proteins. We detected specific binding to thrips midguts when purified G N -S was fed to thrips in an in vivo binding assay. The TSWV nucleoc...

2025, BIO-PROTOCOL

The spatio-temporal expression pattern of a gene provides important indications to better understand its biological function. In situ hybridization (ISH) uses a labeled complementary single-stranded RNA or DNA probe to localize gene transcripts in a whole organism, a whole organ or a section of tissue. We adapted the ISH technique to the plant parasite Meloidogyne spp. (root-knot nematode) to visualize RNAs both in free-living preparasitic juveniles and in parasitic stages settled in the plant tissues. We describe each step of the probe synthesis, digoxigenin (DIG) labeling, nematode extraction from plant tissue, and ISH procedure.

2025, Plant Physiology

Polyamines are a class of low-molecular-weight aliphatic cations with strong biological activities, and they are found in a wide variety of prokaryotic and eukaryotic organisms . Polyamine metabolism, one of the original metabolic pathways present in the last universal common ancestor, is essential for the cell expansion and growth of eukaryotes, archaea, and many bacteria . Therefore, polyamine biosynthesis is commonly used as an example in the analysis of basic evolutionary mechanisms underlying biosynthetic diversity, including gene duplication, horizontal gene transfer, gene fusion, and gene loss. Putrescine (Put) and spermidine (Spd) are by far the most common polyamines in the three domains of life. There are two main pathways of Put synthesis in plants. (1) Arg loses one molecule of urea to form Orn, which loses one molecule of carboxylic acid via the activity of Orn decarboxylase to yield Put. (2) One molecule of carboxylic acid is removed from Arg by arginine decarboxylase (ADC) to yield agmatine; then, one molecule of ammonia is removed by agmatine iminohydrolase to yield N-carbamoyl-putrescine and finally Put. Spermidine synthase (SPDS) catalyzes the conversion of Put to Spd using aminopropyl donated from decarboxylated S-adenosyl methionine (dcSAM), which then can be converted to Spm by spermine synthase (SPMS; Michael, 2016). These enzymes involved in polyamine anabolic synthesis were obtained via

2025, Plant physiology

Polyamines, including putrescine (Put), spermidine (Spd), and spermine (Spm), play essential roles in a wide variety of prokaryotic and eukaryotic organisms. Rice (Oryza sativa) contains four putative spermidine/spermine synthase (SPMS)-encoding genes (OsSPMS1, OsSPMS2, OsSPMS3, and OsACAULIS5), but none have been functionally characterized. In this study, we used a reverse genetic strategy to investigate the biological function of OsSPMS1. We generated several homozygous RNA interference (RNAi) and overexpression (OE) lines of OsSPMS1. Phenotypic analysis indicated that OsSPMS1 negatively regulates seed germination, grain size, and grain yield per plant. The ratio of Spm to Spd was significantly lower in the RNAi lines and considerably higher in the OE lines than in the wild-type (WT), suggesting that OsSPMS1 may function as a spermine synthase. S-adenosyl-L-methionine is a common precursor of polyamines and ethylene biosynthesis. The 1-aminocyclopropane-1-carboxylic acid (ACC) and...

2025, IntechOpen eBooks

Species of genus Trichoderma may benefit as plant pathogen control agent (mycofungicide) and plant growth promoter (biofertilizer) and their application may lower the production costs and environmental impact. Direct effects of these fungi on plant growth and development are crucially important for agricultural uses and for understanding the roles of Trichoderma in natural and managed ecosystems. The Trichoderma potential as bioagent is utilized through the commercial production of Trichoderma-based product. Commercial products of Trichoderma-based biofungicides account for about 60% of the biofungicide market, while the availability and dispersion of Trichoderma-based biofertilizers are more widespread than commonly known with a tendency to expand due to the easier registrations. Limiting factors for availability of commercial products are expensiveness of registration requirements as they must be registered as pesticides, especially patenting, efficacy testing, toxicological, and biosafety testing. This chapter intends to give insight into agricultural importance of Trichoderma and current status of implementation of Trichoderma products in developing and in the developed countries.

2025, International Journal of Design & Nature and Ecodynamics

Colletotrichum sp. and Phytophthora capsici are a causative diseases in chili, they are causing damage up to 50%. Inorganic pesticides are commonly used to treat the diseases, but there are many impacts to plant and consumers of chili. As an alternative, botanical pesticide such as Colletotrichum sp. and Phytophthora capsici are developed massively, since they are good for consumer health. The aim of this research was to evaluate the effectiveness of various botanical extract of Jatropha curcas, Toona sureni, Pangium edule, Syzygium aromaticum and Cymbopogon citratus L as natural antifungal against the Colletotrichum sp. and Phytophthora capsici. The results showed that the inhibition on colony development of Colletotrichum sp. and Phytophthora capsici tested was significant. Extract of P. edule inhibited of Colletotrichum sp. growth at 6 DAI up to 74.06% and P.capsici up to 24.03%. At the same times observation (6 DAI) C. citratus L extract inhibited up to 44.38% colony growth of Colletotrichum sp. and 86.82% colony of P. capsici. Extract of Syzygium aromaticum showed the perfect inhibition (100%) on mycelial growth for P. capsici and 91.71% for Colletotrichum sp. Whereas, J. Curcas and T. sureni extract showed insignificant effect for all fungal pathogen. We are presumed that it because the bioactive compound of the extract. In this research we found that the main compounds of S. aromaticum is eugenol up to 70.97% that we know as antimicrobial.

2025, Genetics

We have identified genes for pathogenicity toward rice (Oryza sativa) and genes for virulence toward specific rice cultivars in the plant pathogenic fungus Magnaporthe grisea. A genetic cross was conducted between the weeping lovegrass (Eragrostis curvula) pathogen 4091-5-8, a highly fertile, hermaphroditic laboratory strain, and the rice pathogen O-135, a poorly fertile, female-sterile field isolate that infects weeping lovegrass as well as rice. A six-generation backcrossing scheme was then undertaken with the rice pathogen as the recurrent parent. One goal of these crosses was to generate rice pathogenic progeny with the high fertility characteristic of strain 4091-5-8, which would permit rigorous genetic analysis of rice pathogens. Therefore, progeny strains to be used as parents for backcross generations were chosen only on the basis of fertility. The ratios of pathogenic to nonpathogenic (and virulent to avirulent) progeny through the backcross generations suggested that the s...

2025, Genetics

Teflon film surfaces are highly conducive to the formation of infection structures (appressoria) in the plant pathogenic fungus, Magnaporthe grisea. We have utilized Teflon films to screen and select for mutants of M. grisea that are defective in appressorium formation. This approach and several others yielded a group of 14 mutants with a similar phenotype. All the mutant strains make abnormally shaped conidia and appressoria. When two mutant strains are crossed, abnormally shaped asci are formed. Ascus shape is normal when a mutant strain is crossed with a wild-type strain. Despite dramatic alterations in cell shape these strains otherwise grow, form conidia, undergo meiosis, and infect plants normally. This mutant phenotype, which we have termed Smo(-), for abnormal spore morphology, segregates in simple Mendelian fashion in crosses with wild-type strains. Some ascospore lethality is associated with smo mutations. In genetic crosses between mutants, smo mutations fail to recombine...

2025, Journal of Coastal Life Medicine

Objective: To investigate the in vitro antimicrobial potential of mangrove associates against a battery of human and shrimp pathogenic bacteria and to elucidate its antimicrobial principles. Methods: In the present study, 12 species of mangrove associates collected from the Kollam (southwest coast of India) vicinity were extracted in different organic solvents of increasing polarity. The resultant extracts obtained from the respective species were examined for the antimicrobial activity against a panel of shrimp and human pathogens by agar diffusion assay. Results: Of the 12 species evaluated, three species of mangrove associates [Calophyllum inophyllum (C. inophyllum), Cerbera odollam and Dalbergia candenatensis] were found to be active. The broadest and highest rank of activity was observed in the crude extract of C. inophyllum. Amongst the pathogens tested, shrimp pathogenic Vibrios were the most sensitive organisms while human pathogens were found to be a bit resistant. In the present study, ethyl acetate was found to be the best solvent for extracting antimicrobial metabolites. The bioactive principles present in the crude extract of C. inophyllum were chemically elucidated by gas chromatography-mass spectrometer. The gas chromatography-mass spectrometer studies revealed the presence of two principal compounds such as 1-Dimethyl(phenyl)silyloxyhexadecane (24.73%) and β-d-Mannofuranoside, O-geranyl (50%) which might play functional role in the chemical defense against microbial invasion. Conclusions: Based on the overall findings, it could be inferred that the mangrove associate C. inophyllum is a promising candidate for the development of plant-based human and veterinary grade antibiotics in future.

2025, Peanut Science

Field studies were conducted during 1997 and 1998 at three different locations in Georgia to determine peanut and weed response to pendimethalin at 1.1 kg ai/ha applied preplantincorporated (PPI) followed by flumioxazin at 71, 87, and 105 g ai/ha applied preemergence (PRE). Other residual treatments combinations with pendimethalin PPI included flumioxazin mixed with metolachlor or dimethenamid PRE, diclosulam PRE, norflurazon PRE, and imazapic applied postemergence (POST). Herbicide combinations that included flumioxazin controlled Florida beggarweed, tropic croton, and small flower morningglory at least 78% or greater. Late season Florida beggarweed control was 90% or greater with pendimethalin PPI plus flumioxazin at 87 to 105 g/ha applied PRE. Pendimethalin plus flumioxazin did not control sicklepod or yellow nutsedge. Smallflower morningglory control with all herbicide treatments was 90% or greater. Entireleaf morningglory control (when used in combination with pendimethalin PPI...

2025, Plant Pathology

High occurrence of Fusarium poae (FP) and Fusarium langsethiae (FL) and their mycotoxins nivalenol (NIV) and T-2/ HT-2 have been observed in Swiss oats. Early prediction of mycotoxin levels is important for farmers and the cereal industry to minimize the risk of contaminated food and feed. Therefore, climate chamber experiments were conducted to investigate the influence of different temperatures (10, 15, 20 °C) and durations (4, 8, 12 h) at 99% relative humidity (RH) on the infection of oats with FP and FL. In addition, to discover the most susceptible period of oats, artificial FL inoculations were conducted at different growth stages. Field experiments were performed to observe the dispersal of these fungal species within the field and to investigate the weather conditions that influence the dispersal. The climate chamber experiments revealed higher contamination with NIV and T-2/HT-2 in the 10 °C treatments and with a prolonged humidity duration of 12 h 99% RH. Inoculations of oat plants at early (DC 61) and mid (DC 65) anthesis, led to higher FL infection and T-2/HT-2 accumulation in the grains compared with treatments at earlier growth stages, which might be due to an increased susceptibility during anthesis. No indication for spore dispersal was observed in the field experiments. The results obtained, together with the cropping factors that influence infection and mycotoxin production, could be used as a first step in developing forecasting models to predict the contamination of oats with the mycotoxins NIV and T-2/HT-2.

2025

Acknowledgements and references In Cameroon, the main quality defects affecting bananas exported towards Europe are related to crown rot of bananas, a post-harvest disease. When harvest, crown are healthy, but after few days of shipment, the fungal infection develops superficially and internally affecting the crowns, then pedicels and ultimately the banana pulp (Figure 1 & 2). This postharvest disease is caused by a broad unspecific and opportunist parasitic complex. Within this complex, Colletotrichum musae is the most pathogenic species. Clusters formation in the packing station involve cut sections that are ways of penetration for pathogens. Fruits contamination can occur within the field, but mainly occurs in the washing tanks in the packing station. Chemical control currently performed is not satisfactory and has to face with: (i) fungicide resistance occuring in fungal populations, (ii) the presence of fungicides residues in fruits skin, (iii) environmental contamination with ...

2025, Plant Pathology

2025, Frontiers in plant science

Strains of Pseudomonas that produce antimicrobial metabolites and control soilborne plant diseases have often been isolated from soils defined as disease-suppressive, i.e., soils, in which specific plant pathogens are present, but plants show no or reduced disease symptoms. Moreover, it is assumed that pseudomonads producing antimicrobial compounds such as 2,4-diacetylphloroglucinol (DAPG) or phenazines (PHZ) contribute to the specific disease resistance of suppressive soils. However, pseudomonads producing antimicrobial metabolites are also present in soils that are conducive to disease. Currently, it is still unknown whether and to which extent the abundance of antimicrobials-producing pseudomonads is related to the general disease resistance of common agricultural soils. Moreover, virtually nothing is known about the conditions under which pseudomonads express antimicrobial genes in agricultural field soils. We present here results of the first side-by-side comparison of 10 repre...

2025, BMC Evolutionary Biology

Background Monoculture, multi-cropping and wider use of highly resistant cultivars have been proposed as mechanisms to explain the elevated rate of evolution of plant pathogens in agricultural ecosystems. We used a mark-release-recapture experiment with the wheat pathogen Phaeosphaeria nodorum to evaluate the impact of two of these mechanisms on the evolution of a pathogen population. Nine P. nodorum isolates marked with ten microsatellite markers and one minisatellite were released onto five replicated host populations to initiate epidemics of Stagonospora nodorum leaf blotch. The experiment was carried out over two consecutive host growing seasons and two pathogen collections were made during each season. Results A total of 637 pathogen isolates matching the marked inoculants were recovered from inoculated plots over two years. Genetic diversity in the host populations affected the evolution of the corresponding P. nodorum populations. In the cultivar mixture the relative frequenc...

2025, International journal of environmental science and development

2025, Mycoscience

Puccinia graminis (Uredinales) is an economically important and common host-alternating rust species on Berberidaceae/Poaceae (subfamilies Pooideae and Panicoideae) that has been spread globally by human activities from an unknown center of origin. To evaluate the taxonomic implications, phylogenetic relationships, and distribution/spread of this complex species, we sequenced and cladistically analyzed the ITS1, 5.8S, and ITS2 regions from herbarium specimens on various host plants from Iran (17), Europe (1), and North America (4). The ITS region plus the 5.8S gene ranged from 686 to 701 bp, including the flanking partial sequences of the 18S and 28S rDNA. Our phylogenetic analysis included 54 bp of the 18S sequence, the entire ITS1 + 5.8S + ITS2, and 58 bp of the 28S sequence. A second analysis used only the last 42 bp of ITS1, and all the 5.8S and ITS2, to incorporate data from additional sequences downloaded from GenBank. In addition to variation in sequence length, there was variation in sequence content. The analysis does not support classical morphology-based taxonomic concepts of the P. graminis complex. Also, host range, host taxonomy, and geographic origin provide minor information on taxonomic relationships. Puccinia graminis is most probably monophyletic. Coevolutionary aspects can hardly be discussed because of lack of sequence data from alternate host specimens. The occurrence of unrelated fungal taxa on the same host species suggests that, besides coevolution with the host, host jumps and hybridization may have played an important role in the evolution of P. graminis. From rDNA data we conclude that the pathogen was intro-

2025, Phytochemistry Letters

2025, Molecular Ecology Resources

Oomycete species occupy many different environments and many ecological niches. The genera Phytophthora and Pythium for example, contain many plant pathogens which cause enormous damage to a wide range of plant species. Proper identification to the species level is a critical first step in any investigation of oomycetes, whether it is research driven or compelled by the need for rapid and accurate diagnostics during a pathogen outbreak. The use of DNA for oomycete species identification is well established, but DNA barcoding with cytochrome c oxidase subunit I (COI) is a relatively new approach that has yet to be assessed over a significant sample of oomycete genera. In this study we have sequenced COI, from 1205 isolates representing 23 genera. A comparison to internal transcribed spacer (ITS) sequences from the same isolates showed that COI identification is a practical option; complementary because it uses the mitochondrial genome instead of nuclear DNA. In some cases COI was mor...

2025, American Journal of Applied Sciences

Pseudomonas aeruginosa has been used in agriculture as biological agents. It has shown substantial control of a variety of soil-borne plant pathogens including Macrophomina phaseolina, Botrytis cinerea, Rhizoctonia solani, Colletotrichum truncatum, Pythium, Fusarium and others. Species aggregate of Pseudomonas aeruginosa strain UPM P3 was shown to have potential as a biocontrol agent against Ganoderma boninense, the causal agent of Basal Stem Rot (BSR) of oil palm. However, P. aeruginosa is also an opportunistic pathogen. It typically infects the pulmonary tract, urinary tract, burns, wounds and also causes other blood infections. The objective of this study was to carry out DNA fingerprinting for strain differentiation to differentiate between pathogenic and non-pathogenic forms of P. aeruginosa strain UPM P3. Approach: Genotype characterization was carried out by amplification of the recA gene using specific primers, purified using QIA Quick PCR purification Kit and sent for sequencing. Multiple sequence alignments were performed on the selected closely related sequence accessions using CLUSTAL W software. The recA gene was used for phylogenetic and PCR-RFLP studies. Results: From the phylogenetic tree, UPM P3 has more than 90% similarity with Pseudomonas aeruginosa strains: PAM7, PAO1, UCBPP-PA14 and PA7. UPM P3 was further digested with restriction enzymes; PvuII, BsrI, ZraI, FokI and SgrAI. RFLP results showed that strain UPM P3 has close similarity with strain PAO1 of Pseudomonas aeruginosa. Conclusion: Strain PAO1 is commonly associated with strains of medical, human or plant pathogens and agricultural environment. Common habitats include soil, hosts, aquatic environment and wastewater and also a common contaminant of public places. Thus the use of Pseudomonas aeruginosa strain UPMP3 as a biological control candidate in agriculture has to be monitored.

2025, Springer

This is a continuation of a series focused on providing a stable platform for the taxonomy of phytopathogenic fungi and fungus-like organisms.

2025, Antimicrobial Agents and Chemotherapy

Azoles are extensively applied in agriculture and medicine, and a relationship between the development of azole resistance in agriculture and the development of azole resistance in clinical practice may exist. The maize pathogen Colletotrichum graminicola , causing cutaneous mycosis and keratitis, has been used to investigate the acquisition of resistance to an agricultural azole and the resulting cross-resistance to various medical antifungal agents. Azole-adapted strains were less sensitive to all azoles tested but showed increased sensitivity to caspofungin, amphotericin B, and nystatin. Viability staining and infection assays with excised human skin confirmed these data.

2025, Plant Disease

Systematics is the study of biological diversity; it is the science that discovers, describes, and classifies all organisms and includes taxonomy, nomenclature, and phylogeny. Scientific names accurately define a set of organisms and are used to communicate about them. As systematic scientists learn more about species, scientific names change to reflect this increased knowledge. Accurately named and precisely defined species reflect what is known about their biology, host range, and geographic distribution. Online resources are available to help users determine the accepted scientific name of fungal plant pathogens. Recent advances in the systematics of fungi are discussed, including the knowledge that: (i) true Fungi are more closely related to animals than to plants; and (ii) the Oomycetes are not true Fungi; rather they are closely related to the yellow-brown algae, known as stramenopiles or Kingdom Chromista. Using molecular data, the higher level classification of true Fungi is...

2025, Biotecnologia Aplicada

State of the art functional genomic tools were used to find, characterize and analyze the function of genes involved with disease resistance in tobacco plants. The identification of genes induced by the interaction of Nicotiana megalosiphon and tobacco blue mold was achieved by suppression subtractive hybridization (SSH), and virus-induced gene silencing (VIGS). Ethylene transcription factor (EIL2) and glutathione synthetase were identified as resistance factors to tobacco blue mold.

2025, Journal of Industrial Microbiology and Biotechnology

Hydroxy fatty acids are plant self-defense substances (Masui et al, Phytochemistry 1989). Three types of hydroxy fatty acids: 10-hydroxystearic acid (HSA), 7S,10S-dihydroxy-8(E)-octadecenoic acid (DOD), and 12,13,17-trihydroxy-9(Z)-octadecenoic acid (THOA) were tested against the following plant pathogenic fungi: Erysiphe graminis f sp tritici (common disease name, wheat powdery mildew); Puccinia recondita (wheat leaf rust); Pseudocercosporella herpotrichoides (wheat foot rot); Septoria nodorum (wheat glume blotch); Pyricularia grisea (rice blast); Rhizoctonia solani (rice sheath blight); Phytophthora infestans (potato late blight); and Botrytis cinerea (cucumber botrytis). At a concentration of 200 ppm, both HSA and DOD showed no fungal disease control activity. However, THOA at the same concentration showed weak activity and provided disease control (percent) of the following plant pathogenic fungi: Erysiphe graminis 77%; Puccinia recondita 86%; Phytophthora infestans 56%; and Botrytis cinerea 63%. The position of the hydroxy groups on the fatty acids seems to play an important role in activity against specific fungi.

2025, HAL (Le Centre pour la Communication Scientifique Directe)

1), Geoffrey Orgeur(2), Valérie Grimault(2), Jean-François Guimbaud (3), Marie-Agnès Jacques(3) (1) GEVES,

2025

S.spinki se conoce como plaga de importancia económica en el cultivo del arroz (Oryza sativa L.) desde la década del setenta en los países del Asia tropical. A finales de 1997 fue detectado en plantaciones de arroz de la región occidental de Cuba, vinculado al hongo Sarocladium oryzae y a una sintomatología caracterizada por un fuerte vaneado y manchado de la panícula y la hoja bandera. El objetivo de este trabajo fue estudiar el comportamiento de su población en relación con diferentes factores bióticos y abióticos en las condiciones de Cuba. En general, los trabajos se realizaron sobre el cultivar Perla de Cuba, en siembras con riego en áreas del Instituto de Investigaciones del Arroz (IIA), La Habana, desde noviembre de 1997 hasta febrero de 1999. El comportamiento de este ácaro estuvo determinado por la fase fenológica y las fechas de siembra. La población máxima coincidió con la fase de emersión o salida de la panícula, y fue mayor en las plantaciones germinadas en marzo y juli...

2025, Revista Iberica De Aracnologia

Pp: 91 -97. Steneotarsonemus is considered one of the most agriculturally important genera of tarsonemid mites, and is second in number of species diversity in the family. A new species, Steneotarsonemus lobosus sp. n., is described and... more

2025, European Journal of Plant Pathology

Trichoderma isolates are known for their ability to control plant pathogens. It has been shown that various isolates of Trichoderma, including T. harzianum isolate T-39 from the commercial biological control product TRICHODEX, were effective in controlling anthracnose (Colletotrichum acutatum) and grey mould (Botrytis cinerea) in strawberry, under controlled and greenhouse conditions. Three selected Trichoderma strains, namely T-39, T-161 and T-166, were evaluated in large-scale experiments using different timing application and dosage rates for reduction of strawberry anthracnose and grey mould. All possible combinations of single, double or triple mixtures of Trichoderma strains, applied at 0.4% and 0.8% concentrations, and at 7 or 10 day intervals, resulted in reduction of anthracnose severity; the higher concentration (0.8%) was superior in control whether used with single isolates or as a result of combined application of two isolates, each at 0.4%. Only a few treatments resulted in significant control of grey mould. Isolates T-39 applied at 0.4% at 2 day intervals, T-166 at 0.4%, or T-161 combined with T-39 at 0.4% were as effective as the chemical fungicide fenhexamide. The survival dynamics of populations of the Trichoderma isolates (T-39, T-105, T-161 and T-166) applied separately was determined by dilution plating and isolates in the mixtures calculated according to the polymerase chain reaction (PCR) using repeat motif primers. The biocontrol isolates were identified to the respective species T. harzianum (T-39), T. hamatum (T-105), T. atroviride (T-161) and T. longibrachiatum (T-166), according to internal transcribed spacer sequence analysis.

2025, PloS one

Genetic resistance is the most effective and sustainable approach to the control of plant pathogens that are a major constraint to agriculture worldwide. In soybean, three dominant R genes, i.e., Rsv1, Rsv3 and Rsv4, have been identified and deployed against Soybean mosaic virus (SMV) with strain-specificities. Molecular identification of virulent determinants of SMV on these resistance genes will provide essential information for the proper utilization of these resistance genes to protect soybean against SMV, and advance knowledge of virus-host interactions in general. To study the gain and loss of SMV virulence on all the three resistance loci, SMV strains G7 and two G2 isolates L and LRB were used as parental viruses. SMV chimeras and mutants were created by partial genome swapping and point mutagenesis and then assessed for virulence on soybean cultivars PI96983 (Rsv1), L-29 (Rsv3), V94-5152 (Rsv4) and Williams 82 (rsv). It was found that P3 played an essential role in virulence...

2025

Nectria haematococca mating population I (MPI, anamorph, Fusarium solani f. sp. cucurbitae race 1) is the causal agent of Fusarium crown and foot rot disease of cucurbits. It occurs worldwide, causing serious damages on the cucurbits cultivations. Although genetic studies on this fungus were ahead of genetic analysis of other plant pathogenic fungi in early 1940s, such investigations ceased after 1970. For performing genetic analysis, irrespective of whether it is conventional or molecular, and also in pursuing whole genome sequencing, information of karyotype is the underlying basis. As to the karyotype of N. haematococca MPI, cytological investigations were done more than 50 years ago, in which haploid chromosome number (CN) of this fungus was estimated to be n=4, Thereafter, no additional data have been added to the cytological karyotype of this fungus. In this study, I present a reliable karyotype of this important plant pathogen, N. haematococca MPI using two standard strains ATCC18098 and ATCC18099, by combining molecular and cytological karyotyping methods. In addition, a mini-chromosome discovered during the course of karyotyping was analyzed for its cytological nature and meiotic inheritance mode. Molecular karyotyping using pulsed field gel electrophoresis (PFGE) of ATCC18098 and ATCC18099 was attempted using a standard running condition of PFGE suitable to separate chromosomes below ~ 6 Mb. Results showed apparent similarity in the banding pattern of the two strains and two middlesized chromosome bands were clearly resolved. The two bands migrated similarly between the two strains and their sizes were estimated to be ~ 3.5 and ~ 2.5 Mb. Besides these bands, an extra small band was detected in ATCC18098 with a size of ca. 410 kb. Southern hybridization of this band with telomere repeats (TTAGGG)n from Neurospora crassa as a probe showed the presence of telemetric repeats within this band suggesting that this band is a miniv In the name of Allah Most Gracious Most Merciful. All praise and thanks to Allah the exalted, the Lord of the universe, May the choicest blessings and peace of Allah be upon the last Messenger and Prophets, Muhammad, his family, Companions and all those who follow his footsteps. I am very grateful to Associate Prof. Dr. Masatoki Taga for suggesting the point, his precise instructions through the study, for many helpful discussions, for critical reading the manuscript, for his patience and kindheartedness and for his unlimited and unconditional support during the past years. I appreciate Prof. Kamada for his support and fruitful discussions, Prof. Takahashi Taku for his supervision and Dr. Muraguchi (Akita Prefectural University) for providing the Operon RAPD primers. I also appreciate to all former and current members of Dr. Taga' lab: Nishima, Tsuchiya, Kaneko, Songlin, Arimoto, Ogura, Nishizawa and my brother Hamid for their encouragement, support, and fun time together. Last but not least, I want to thank my dear wife and children for unconditional love and infinite patience, my family and my family-in-law for encouragement and support, the Egyptian group in Okayama for their endless support and to all the members of Okayama muslim community.

2025, Proceedings of the National Academy of Sciences

The production of lytic enzymes in Trichoderma is considered determinant in its parasitic response against fungal species. A mitogen-activated protein kinase encoding gene, tvk1 , from Trichoderma virens was cloned, and its role during the mycoparasitism, conidiation, and biocontrol was examined in tvk1 null mutants. These mutants showed a clear increase in the level of the expression of mycoparasitism-related genes under simulated mycoparasitism and during direct confrontation with the plant pathogen Rhizoctonia solani . The null mutants displayed an increased protein secretion phenotype as measured by the production of lytic enzymes in culture supernatant compared to the wild type. Consistently, biocontrol assays demonstrated that the null mutants were considerably more effective in disease control than the wild-type strain or a chemical fungicide. In addition, tvk1 gene disruptant strains sporulated abundantly in submerged cultures, a condition that is not conducive to sporulatio...

2025, Genome biology

Mycoparasitism, a lifestyle where one fungus is parasitic on another fungus, has special relevance when the prey is a plant pathogen, providing a strategy for biological control of pests for plant protection. Probably, the most studied... more

2025

This study was carried out in order to test the efficacy of C. erectus alcoholic extract and gibberellic acid to control potato soft rot bacterial disease caused by the bacteria type E. c. sub sp. carotovora was investigated. The inhibition ability of the extract at 250, 500 and 1000 ppm concentrations was examined on nutrient agar (N.A) medium. Each concentration was mixed with the medium before solidification then inoculated with the bacterial pathogen. The highest inhibition percentage of Conocarpus was %86.1 at 1000 ppm concentration. In pots experiments, the lowest percentage of infection was %0.00 for tubers treated with 1000 ppm of conocarpus and 1.5g/L beltanol pesticide compared to control which was 41.14%. Whereas inhibition percentages were 6.77, 4.85 and 2.67 respectively, for all three concentration of conocarpus treated in compared to control which was %34.15, in the field experiment Potato grown in pots treated with 500 and 1000 ppm scored the highest tubers weight wh...

2025, Current Genetics

The main molecular factors involved in the complex interactions occurring between plants (bean), two diVerent fungal pathogens (Botrytis cinerea, Rhizoctonia solani) and an antagonistic strain of the genus Trichoderma were investigated. Two-dimensional (2-D) electrophoresis was used to analyze separately collected proteomes from each single, two-or three-partner interaction (i.e., plant, pathogenic and antagonistic fungus alone and in all possible combinations). DiVerential proteins were subjected to mass spectrometry and in silico analysis to search for homologies with known proteins. In the plant proteome, speciWc pathogenesis-related proteins and other disease-related factors (i.e., potential resistance genes) seem to be associated with the interaction with either one of the two pathogens and/or T. atroviride. This Wnding is in agreement with the demonstrated ability of Trichoderma spp. to induce systemic resistance against various microbial pathogens. On the other side, many diVerential proteins obtained from the T. atroviride interaction proteome showed interesting homologies with a fungal hydrophobin, ABC transporters, etc. Virulence factors, like cyclophilins, were up-regulated in the pathogen proteome during the interaction with the plant alone or with the antagonist too. We isolated and conWdently identiWed a large number of protein factors associated to the multi-player interactions examined.

2025

The presence of naturally occurring entomopathogenic nematodes was surveyed in the Mediterranean Region of Turkey. Fiftytwo soil samples were taken, using the Galleria larva bait technique. Three soil samples were found positive. One sample contained Steinernema carpocapsae (Rhabditida: Steinernematidae) and two samples contained Heterorhabditis bacteriophora (Rhabditida: Heterorhabditidae). Morphometric characteristics are given. S. carpocapsae is recorded for the first time in the nematofauna of Turkey.

2025, Kanoje T

Govt. D. B. Girls P. G. (Autonomous) College Raipur (C.G.) 2 Govt. Arts and Commerce Girls College Devendra Nagar Raipur (C.G.

2025, Nature

Xylella fastidiosa is a fastidious, xylem-limited bacterium that causes a range of economically important plant diseases. Here we report the complete genome sequence of X. fastidiosa clone 9a5c, which causes citrus variegated chlorosis--a serious disease of orange trees. The genome comprises a 52.7% GC-rich 2,679,305-base-pair (bp) circular chromosome and two plasmids of 51,158 bp and 1,285 bp. We can assign putative functions to 47% of the 2,904 predicted coding regions. Efficient metabolic functions are predicted, with sugars as the principal energy and carbon source, supporting existence in the nutrient-poor xylem sap. The mechanisms associated with pathogenicity and virulence involve toxins, antibiotics and ion sequestration systems, as well as bacterium-bacterium and bacterium-host interactions mediated by a range of proteins. Orthologues of some of these proteins have only been identified in animal and human pathogens; their presence in X. fastidiosa indicates that the molecul...

2025, eLife

Due to their economic relevance, the study of plant pathogen interactions is of importance. However, elucidating these interactions and their underlying molecular mechanisms remains challenging since both host and pathogen need to be fully genetically accessible organisms. Here we present milestones in the establishment of a new biotrophic model pathosystem: Ustilago bromivora and Brachypodium sp. We provide a complete toolset, including an annotated fungal genome and methods for genetic manipulation of the fungus and its host plant. This toolset will enable researchers to easily study biotrophic interactions at the molecular level on both the pathogen and the host side. Moreover, our research on the fungal life cycle revealed a mating type bias phenomenon. U. bromivora harbors a haplo-lethal allele that is linked to one mating type region. As a result, the identified mating type bias strongly promotes inbreeding, which we consider to be a potential speciation driver.

2025

Orientadores: Anete Pereira de Souza, Alessandra Alves de SouzaTese (doutorado) - Universidade Estadual de Campinas, Instituto de BiologiaResumo: Interações planta-patógeno possuem uma ampla participação de mecanismos moleculares que dirigem todo o processo de manutenção e disseminação do patógeno em seu hospedeiro. X. fastidiosa é uma bactéria fitopatogênica com grande repercussão em importantes culturas agronômicas no mundo, como, por exemplo, na citricultura brasileira. Estudos acerca da compreensão dos mecanismos de patogenicidade de X. fastidiosa puderam ser melhor desenvolvidos após o sequenciamento do seu genoma, gerando novas informações e questionamentos em relação ao seu comportamento biológico e molecular. Desta forma, o presente trabalho tem por objetivo caracterizar a função da proteína VapD, acrônimo em inglês designado para virulence-associated protein D, produto da ORF XFb0051. Para tanto, foram utilizadas técnicas de imunodetecção por western blot para avaliação da ...

2025, International Journal of Agricultural and Biosystems Engineering

A Field experiment was carried out to evaluate the effects of some bacterial fertilizers on some parameters growth and yield of two cultivars of watermelon during the season 2018-2019. The study included two factors the first factor was two cultivars of watermelon (Top yield and Charleston Gray) the second factor was bacterial fertilizer {control, Azospirillium barsilense (B1), Azotobacter chrococum (B2), Azospirillium barsilens+fluorescens Pseudomona (B3), Azotobacter chrococum+fluorescens Pseudomona (B4) and B1+B2+Pseudomona fluorescens (B5)}. Minimum days for germination were obtained from B4 (Azotobacter chrococum+fluorescens Pseudomona)+genotype Top yield (4.83 days). The highest percentage of phosphorus, potassium and iron was obtained in B5 treatment with combination bacterial fertilizer with cultivar of Top Yield (0.394%, 3.443% and 377.1mg matter dry-1 respectively). The maximum percentage TSS was observed in B5 treatment with Top Yield (10%). The best significant effect on yield production was obtained in B5 treatment with cultivar of Top Yield (134.93 ton per hector) compared to control treatment with cultivar of Charleston Gray (66.67 ton per hector).

2025, Phytopathology

Genes for copper resistance, located on the chromosome of strain XvP26 of Xanthomonas axonopodis pv. vesicatoria, were transferred by conjugation to a recipient strain of the bacterium. The chromosomal gene transfer was verified by analyses of the genomes of donor, recipient, and putative transconjugants for plasmid profiles, by polymorphism of DNA bands obtained by digesting total genomic DNA by a rare-cutting endonuclease and pulsed-field gel electrophoresis, and by Southern hybridization with a probe containing the copper genes. Transfer of kanamycin resistance to a recipient strain, associated with Tn5 insertion into the chromosome of another strain of the bacterial spot pathogen, was also verified. The fre-quency of kanamycin resistance transfer to recipient was more than 75 times greater in pepper leaves than in vitro. The transfer of chromosomal sequences containing the hypersensitive reaction and pathogenicity (hrp) genes and pigmentation (pig) genes was linked with transfer of kanamycin resistance (Tn5). Horizontal transfer in planta of the chromosomal genes (i.e., cop, pig, hrp, and Tn5 sequences) among strains of X. axonopodis pv. vesicatoria means that horizontal chromosomal gene transfer is possible in nature. This type of gene transfer may explain the presence of great diversity among strains of the bacterial spot pathogen in terms of DNA polymorphism and may also explain the apparent horizontal transfer of hrp sequences among pathovars of Xanthomonas.

2025, PGPR: Biocontrol and Biofertilization

Use of plant growth promoting rhizobacteria (PGPR) for the benefits of agriculture is gaining worldwide importance and acceptance and appears to be the trend for the future. PGPR are bioresources which may be viewed as a novel and potential tool for providing substantial benefits to the agriculture. These beneficial, free-living bacteria enhance emergence, colonize roots, stimulate growth and enhance yield. PGPR are known to induce resistance against various plant pathogens in different crops ranging from cereals, pulses, ornamentals, vegetables, plantation crops, spices and some trees. Most studies have emphasized exploration and potential benefits of PGPR in agriculture, horticulture and forestry. The plausible mechanisms adopted by these rhizobacteria in growth promotion and resistance, though abundantly documented but still remains to be fully explored. Integrated use of PGPR allows the combination of various mechanisms thereby enhancing their beneficial abilities. However, their use has not been to the full potential due to inconsistency in their performance and their commercialization limited to few developed countries. Use of PGPR as bioinoculants, biofertilizers and biocontrol agents, advantages and disadvantages, practical potential in improved agriculture and future prospects are also discussed.

2025, Journal of The Institute of Brewing

Two basic proteins were isolated to homogeneity from malting barley (Hordeum vulgare L.) grain. Proteins were identified as members of a Thaumatin-Like Protein (TLP) family, by Western blot. Isoforms, assigned as TLP-S and TLP-R, have slightly different mobility at about 22 and 27 kDa in nonreducing and reducing conditions, and pI values of 9.5 and 9.4, respectively. The antifungal potency of malting barley grain TLPs isoforms was examined on Micrococcus lysodeikticus, Saccharomyces cerevisiae, Candida albicans and plant pathogen Fusarium sporotrichioides growth in vitro. It was found that that IC 50 value for TLP-S was two fold higher. Antibacterial and antifungal activities of both isoforms were completely abolished by divalent (Ca 2+ , Mn 2+ , Mg 2+ ) and monovalent (K + ) cations, at concentrations approximating physiological ionic strength and higher. Glucanase activity was not observed; neither TLP-S nor TLP-R digested glucan. On the basis of these results, the importance of TLP for barley grain protection against fungal diseases has been discussed together with the mechanism of antimicrobial action.