Alternaria Blight Research Articles

In-vitro Evaluation of Trichoderma Species and Some Selected Botanical Extracts against Alternaria helianthi (Hansf) Causing Alternaria Blight of Sunflower

This study investigates the in vitro efficacy of bioagents and selected botanicals in managing Alternaria helianthi, the pathogen responsible for Alternaria blight in sunflower (Helianthus annuus L.). Two bioagents, Trichoderma harzianum and Trichoderma viride, and six botanicals—Azadirachta indica (neem), Lantana camara (lantana), Curcuma longa (turmeric), Aloe barbadensis (aloe vera), Withania somnifera (ashwagandha), and Mentha spicata (pudina)—were evaluated using the dual culture and poison food technique, respectively. The results showed that T. harzianum exhibited the highest inhibition of mycelial growth at 76.32%, while neem extract was the most effective among botanicals, achieving a maximum inhibition of 75.03% at 15% concentration. These findings suggest the potential of bioagents and botanicals in eco-friendly management strategies for Alternaria blight in sunflower cultivation.

Disease Indexing of Rapeseed: Mustard Cultivars against Alternaria Blight

In the investigation, 120 rapeseed-mustard genotypes were screened under in vivo conditions for resistance against the foliar disease Alternaria blight. None of the genotypes were found to be immune to the disease. However, three genotypes—JT-1, RVM-3, and Pusa Jagannath—were identified as resistant (R), with disease severity ranging from 1% to 10%. Nine genotypes were classified as moderately resistant (MR), showing disease severity between 11% and 25%. A total of 67 genotypes were rated as moderately susceptible (MS), with disease severity ranging from 26% to 50%. Additionally, 41 genotypes were categorized as susceptible (S), where disease severity was between 51% and 75%. The highly susceptible none of genotypes were found.

Screening of linseed genotypes for resistance against Alternaria blight and powdery mildew in linseed (Linum usitatissimum L.)

Screening of linseed genotypes for resistance against Alternaria blight and powdery mildew in linseed (Linum usitatissimum L.)

In vitro Effect of Bio-agents for Control of Alternaria Blight of Indian Mustard Incited by Alternaria brassicicola

In vitro Effect of Bio-agents for Control of Alternaria Blight of Indian Mustard Incited by Alternaria brassicicola

Role of defense inducers in modulating biochemical responses to Alternaria leaf blight

Alternaria leaf blight of sunflower has been considered as a potentially destructive disease. Due to cons of using chemical pesticides, the present investigation was undertaken to know the effect of three plant defence inducers viz., salicylic acid, monopotassium phosphate and sodium propionate for the eco-friendly management of Alternaria leaf blight disease. Seed treatment with salicylic acid at 100 ppm followed by foliar spray of salicylic acid at 100 ppm recorded highest secondary metabolites such as flavonoids (68.71 mg g FW) and phenols (73.53 mg g FW) -1 -1 -1 when compared to phenolics (45.07 mg g FW) and flavonoids (51.43 mg g FW) in control plants -1 . Seed treatment with salicylic acid at 100 ppm followed by foliar spray of salicylic acid at 100 ppm showed increased defense enzymes such as superoxide dismutase (40.45 mg/50 per cent inhibition) and peroxidase (16.86 mg min mg protein) when compared to superoxide dismutase -1 -1 (54.36 mg/50 per cent inhibition) and peroxidase (9.63 mg min mg protein) in control plants. This study -1 -1 demonstrated that seed treatment followed by foliar spray with salicylic acid can be used effectively for the management of Alternaria blight in fields as it exhibited more defense enzyme activity and secondary metabolites.. KEYWORDS :Alternaria, defense enzymes, secondary metabolites, seed treatment

Harnessing nature's defenders: unveiling the potential of microbial consortia for plant defense induction against Alternaria blight in cumin.

Present study was aimed to develop an efficient microbial consortium for combating Alternaria blight disease in cumin. The research involved isolating biocontrol agents against Alternaria burnsii, characterizing their biocontrol and growth promotion traits, and assessing compatibility. A pot experiment was conducted during rabi season of 2022-2023 to evaluate the bioefficacy of four biocontrol agents (1F, 16B, 31B, and 223B) individually and in consortium, focusing on disease severity, plant growth promotion, and defense responses in cumin challenged with A. burnsii. Microbial isolates 1F, 16B, 31B, and 223B significantly inhibited A. burnsii growth in dual plate assays (~ 86%), displaying promising biocontrol and plant growth promotion activities. They were identified as Trichoderma afroharzianum 1F, Aneurinibacillus aneurinilyticus 16B, Pseudomonas lalkuanensis 31B, and Bacillus licheniformis 223B, respectively. The excellent compatibility was observed among all selected biocontrol agents. Cumin plants treated with consortia of 1F + 16B + 31B + 223B showed least percent disease index (32.47%) and highest percent disease control (64.87%). Consortia of biocontrol agents significantly enhanced production of secondary metabolites (total phenol, flavonoids, antioxidant, and tannin) and activation of antioxidant-defense enzymes (POX, PPOX, CAT, SOD, PAL, and TAL) compared to individual biocontrol treatment and infected control. Moreover, consortium treatments effectively reduced electrolyte leakage over the individual biocontrol agent and infected control treatment. The four-microbe consortium significantly enhanced chlorophyll (154%), carotenoid content (88%), plant height (78.77%), dry weight (72.81%), and seed yield (104%) compared to infected control. Based on these findings, this environmentally friendly four-microbe consortium may be recommended for managing Alternaria blight in cumin.

Unravelling the Potential Use of Newer Fungicides against Alternaria Blight of Indian Mustard under In vivo

Unravelling the Potential Use of Newer Fungicides against Alternaria Blight of Indian Mustard under In vivo

Identification, phylogeny, pathogenicity and management of Alternaria burnsii (Uppal, Patel and Kamat) causing blight of cumin

Alternaria blight is one of the important diseases of cumin. The disease initiation was observed at nearly one month age of the crop during warm humid weather in the epidemic form at flowering stage and seeds could not mature to full size. The pathogen was isolated by tissue isolation technique. Pathogenicity test was proved by following Koch’s postulates. The pathogen was identified as Alternaria burnsii based on morphological characters and ITS sequencing. The sequence was submitted to gene bank NCBI and it was accepted by NCBI with accession number MT856660. For effective control of cumin blight with fungicides a field experiment was conducted. Efficacy of eight fungicides was tested under field condition for disease intensity and yield of cumin. Among the eight combined and single fungicides, Azoxystrobin 11% + Tebuconazole 18.30% SC at concentration 0.044% was most effective with 14.76% least mean disease intensity and highest yield of 907 kg/ha followed by Metiram 55 % + Pyraclostrobin 5 % WG at concentration 0.18% with 18.27% least mean disease intensity and yield of 889 kg/ha.

Molecular marking in a white cabbage selection for resistance to Alternaria Blight

In the presented study, the polymorphism of SSR loci was studied on the basis of the resistance of white cabbage to alternariosis. This work was carried out in order to identify effective and informative ISSR markers for the identification of donor alleles of resistance to alternariosis in the genotypes of hybrid plants of culture. Of the 20 tested markers, only 3 (PBCESSRJU13, PBCESSRJU6, NI-F02a) demonstrate an allelic difference between the isogenic lines of white cabbage contrasting in resistance to Alternaria Blight. They will become the basis for subsequent studies on the analysis of cleavage in segregating populations and the determination of informative DNA marker systems co-inherited with the sign of resistance of cabbage to alternariosis.

Evaluation of the effectiveness of fungicides in suppression Alternaria blight and Pho-ma rot on spring rapeseed

Evaluation of the effectiveness of fungicides in suppression Alternaria blight and Pho-ma rot on spring rapeseed

Exogenous Application of Defence Signalling Compounds Stimulate Natural Defence Responses against Alternaria Blight and Seed Quality in Radish

Exogenous Application of Defence Signalling Compounds Stimulate Natural Defence Responses against Alternaria Blight and Seed Quality in Radish

Evaluate the effect of essential oils on disease incidence of Alternaria blight of sunflower Alternaria helianthi

Evaluate the effect of essential oils on disease incidence of Alternaria blight of sunflower Alternaria helianthi

RACHNA CANOLA (RBN-13016): A HIGH-YIELDING RAPESEED CULTIVAR ENRICHED WITH OMEGA-3 AND OMEGA-9 FATTY ACIDS

Rapeseed oil is the prime source of two essential fatty acids, Omega-3 (alpha-linolenic acid), and Omega-6 (linoleic acid). Oleic acid is a mono-unsaturated omega-9 fatty acid that is also available in rapeseed oil in good ratio. To improve quality of edible oil and seed yield in rapeseed, comprehensive research was conducted at Oilseeds Research Institute Faisalabad (Pakistan) to evolve rapeseed cultivars requiring qualitative and quantitative characteristics with broader adaptability. The pedigree method of selection was used after hybridization (Legend x RBN-03052) during 2006-07, and homozygous progenies of 6016-B from F6 were bulked during 2012-13 for seed yield evaluation in different agroclimatic regions. Its performance was evaluated in the station and sixteen outstation seed yield trials from 2014 to 2020. Additive main effect and multiplication interaction analysis (AMMI) was performed to investigate the performance of promising line RBN-13016 along with checking Super Canola and both parents RBN-03052 (female parent) and Legend-1 (male parent) at sixteen ecological environments of Pakistan. Additive main effect and multiplication interaction analysis was done to estimate the responses of genotype, environment, and genotype x environment interactions based on seed yield. It has proved its worth in seed yield trials, and its performance was significantly better than the check variety and its parents. Rachna Canola (RBN-13016) was specifically bred for high Omega-3 (alpha-linolenic acid) and Omega-9 (Oleic acid), which were found to be significantly higher than the check variety as well as its parents. Other quantitative traits included medium maturing period, bold seed, long silique, lodging tolerance, Alternaria blight resistance, white rust resistance, high seed yield potential, good oil protein content, and broader adaptability. Based on high seed yield, high Omega-3 (9.14%) and Omega-9 (72.17%), the Punjab Seed Council (Pakistan) approved RBN-13016 as the variety “Rachna Canola” for general cultivation. Due to versatility in characteristics, this rapeseed cultivar can be effectively grown in different regions and countries with the same prevailing climatic conditions as in Pakistan.

Efficiency of application of the complex based on pseudomonas fluorescens bacteria on potato plantations in the Western Forest Steppe of Ukraine

Goal. To form effective complexes based upon bacterium Pseudomonas fluorenscens in combination with stimulation growth preparations and microelements with their efficiency study on potato plantations.
 Methods. The researches conducted during 2021—2022 in breeding- seeding rotation on the base Ukrainian Research Plant Quarantine Station of Institute of Plant Protection of NAAS. The experiment conducted on variety Slovyanka. The preparations efficiency determined in different rates against fungi diseases. Records conducted as per generally approved techniques with experimental methods in plant pathology and plant protection.
 Results. The efficiency of complex based upon Pseudomonas fluorescens АР-33 with stimulating matter nature and chelated microelementson potato plantations in growing period. The yield increased in 1.1—1.5 times during chelate 1 adding to preparation based upon bacterium Pseudomonas fluоrescens, and it increased in 1.3—1.6 times during chelate 2 addition. All biocomplexes combinations showed the preparation efficiency against Alternaria blight in scope 41.5—66.8%, but for late blight it had the following indexes 65.6—85.2.
 Conclusions. Combinations with chelates № 2 (Fe + Mn + Zn + Mo + Co + B) provided best growing results and yield. The combination Pseudomonas fluоrescens + xymedon + accinic acid + DMAE2ml/l + DМSО2 ml/l chelate (3.6%) showed the best result against potato Alternaria blight. It’s efficiency consisted of 66.8%.The combination Pseudomonas fluоrescens + xymedon + accinic acid + DMAE2ml/l + DМSО2 ml/l chelate(3.6%) showed 85.2% against late blight. It was the best index.

Global Scenario of Vegetable Fungal Diseases

Plant diseases threaten crop production and are responsible for considerable losses in vegetables worldwide. Every year diseases cause losses up to 40 to 60% in vegetable crops. Vegetable crops are comparatively more susceptible to various types of diseases inflicted by fungi, bacteria, virus, viroid, phytoplasma and nematodes. Genera of fungal pathogens viz. Alternaria, Aschochyta, Colletotrichum, Didymella, Phoma, Phytophthora, Pythium, Rhizoctonia, Sclerotinia and Sclerotium on vegetable crops increased tremendously. Emerging seed-borne and seed-transmitted fungal plant diseases became a major threat for the vegetable seed production system. Emerging diseases in vegetable crops like tomato (early and late blight, Fusarium wilt), chili and peppers (anthracnose, Phytophthora blight), brinjal (phomopsis blight, Alternaria leaf spot), cucurbits (Downey mildew, gummy stem blight, Fusarium wilt, fruit rot, anthracnose and Cercospora leaf spot), okra (Cercospora leaf spot), pea (powdery mildew, fusarium wilt, rust and root rot), French bean (Sclerotinia stem rot), cowpea/dolichos bean (anthracnose, Sclerotinia stem rot), cole crop (black rot, Alternaria blight, downy mildew) etc. The vegetable produce is spoiled by post-harvest pathogens and makes them unfit for human consumption and market due to the production of mycotoxins. Profiling, detection and diagnosis of vegetable pathogens (diseases) are essential for better understanding of pathogens and formulation of safe disease management strategy of vegetable crops. Therefore, there is an urgent need to wide array of diagnoses of pathogens of vegetables and their in-vitro testing towards chemo-sensitivity for formulation of safe management of vegetable diseases

Epidemiological study of Alternaria blight of cabbage in Jorhat district of Assam, India

The field experiment conducted during the period of 2021-2022 at the Department of Horticulture, AAU, Jorhat, has shown that the timing of transplantation significantly impacts the severity of Alternaria blight in cabbage. The study revealed that the timing of transplanting significantly affects disease severity. The crop transplanted in the month of December exhibited the highest disease intensity (maximum and minimum temperatures 24.76°C and 10.58°C, morning and evening relative humidity 98.41% and 57.13% respectively). The disease intensity was the lowest in October transplanted crops (maximum and minimum temperature 26.94°C and 12.22°C, relative humidity morning 96.12% and evening 55.13% respectively). The December transplanted crop had the highest AUDPC at 1317.75, followed by the February transplanted crop at 1037.85. With respect to the correlation matrix, rainfall and relative humidity showed a strong positive correlation with PDI whereas BSSH and temperature (maximum and minimum) all revealed a negative correlation. The multiple regression analysis revealed a substantial relation between disease intensity and meteorological conditions. The multiple regression equation indicated that the overall influence of all environmental parameters, namely (maximum and minimum) temperature, (morning and evening) relative humidity, rainfall, and BSSH on disease development ranged from 63.19% to 82.94%.

Comparative transcriptome profiling reveals differential defense responses among Alternaria brassicicola resistant Sinapis alba and susceptible Brassica rapa.

Alternaria blight is a devastating disease that causes significant crop losses in oilseed Brassicas every year. Adoption of conventional breeding to generate disease-resistant varieties has so far been unsuccessful due to the lack of suitable resistant source germplasms of cultivated Brassica spp. A thorough understanding of the molecular basis of resistance, as well as the identification of defense-related genes involved in resistance responses in closely related wild germplasms, would substantially aid in disease management. In the current study, a comparative transcriptome profiling was performed using Illumina based RNA-seq to detect differentially expressed genes (DEGs) specifically modulated in response to Alternaria brassicicola infection in resistant Sinapis alba, a close relative of Brassicas, and the highly susceptible Brassica rapa. The analysis revealed that, at 48 hpi (hours post inoculation), 3396 genes were upregulated and 23239 were downregulated, whereas at 72 hpi, 4023 genes were upregulated and 21116 were downregulated. Furthermore, a large number of defense response genes were detected to be specifically regulated as a result of Alternaria infection. The transcriptome data was validated using qPCR-based expression profiling for selected defense-related DEGs, that revealed significantly higher fold change in gene expression in S. alba when compared to B. rapa. Expression of most of the selected genes was elevated across all the time points under study with significantly higher expression towards the later time point of 72 hpi in the resistant germplasm. S. alba activates a stronger defense response reaction against the disease by deploying an array of genes and transcription factors involved in a wide range of biological processes such as pathogen recognition, signal transduction, cell wall modification, antioxidation, transcription regulation, etc. Overall, the study provides new insights on resistance of S. alba against A. brassicicola, which will aid in devising strategies for breeding resistant varieties of oilseed Brassica.

Diseases prevalent in Kharif crops grown in Barmer district of Rajasthan, India

In the Kharif season, pearl millet (Pennisetum glaucum) is the predominant crop of the Barmer district followed by cluster bean (Cyamopsis tetragonoloba) and moth bean (Vigna aconitifolia). Sesame (Sesamum indicum) and green gram (Vigna radiata) are other important Kharif oilseed and pulse crops, respectively. A survey was conducted to determine the status of major diseases of Kharif crops grown in the Barmer district of the Marwar region of Rajasthan, India. Five blocks and three villages in each block were surveyed through a random field survey method during the collection of diseased samples every Sunday for the practical classes of agricultural students of the College of Agriculture, Baytu; in August and September 2023. Per cent disease incidence was recorded on randomly selected plants in a particular field of selected location. The incidence of diseases was observed based on typical field symptoms and later the association was confirmed through microscopic examinations in the laboratory. In survey, yellow mosaic (virus), leaf crinkle/ curl (virus), bacterial leaf spot/ blight (Xanthomonas phaseoli) of green gram;green ear/ downy mildew (Sclerospora graminicola), rust (Puccinia substriata) and blast (Pyricularia grisea) of pearl millet; Phytophthora stem blight (Phytophthora parasitica var. sesame) and phyllody (Phytoplasma) of sesame; yellow mosaic (virus)and bacterial leaf spot/ blight (Xanthomonas axonopodis pv. cyamopsidis) of cluster beanwere recorded with >50% incidence. However; charcoal rot (Macrophomina phaseolina), web blight (Rhizoctonia solani), Cercospora leaf spot (Cercospora canescens) and anthracnose (Colletotrichum lindemuthianum) of green gram; Alternaria blight/ leaf spot (Alternaria sesame) of sesame,sorghum rust (Puccinia purpurea) and Alternaria blight/ leaf spot (Alternaria cyamopsidis) of cluster beanwere noticed with 10 to 50% incidence.

Apple tree Alternaria (malus domestica Borkh.) and ways to reduce its harmfulness in the non-chernozem zone of Russia

The research was conducted on the territory of the educational and experimental farm of the K.A. Timiryazev Russian State Agrarian University of Agriculture in Moscow in 2020-2023. The examination of apple-tree plantings, ornamental plantings, and weed vegetation was carried out for three years with determination of pathogens of the main diseases by microscopy method. The Alternaria fungi species membership were identified by morphological features of conidia and sporulation habitus, and the specific pathogen species was confirmed by PCR analysis. Two unspecified species of Alternaria tenuissima and Alternaria infectoria fungi were found to infect apple trees and other species of the surveyed plants with Alternaria blight. The fungus species Alternaria tenuissima was predominantly recorded on apple trees. Out of 186 examined apple cultivars, the development of Alternaria blight was found in 85.5% of the cultivars with different ripening periods. The apple cultivars most resistant to Alternaria blight were identified. The apple cultivars, in which the damage of fruits by Alternaria blight was recorded, were identified. Infestation of apple seeds by fungi of Alternaria genus obtained from fruits affected by this pathogen was determined. The possibility of high Alternaria blight infestation degree in apple tree seedlings was detected. A high degree of Alternaria tenuissima and Alternaria infectoria fungi development was recorded in a number of orchard-protecting and ornamental plants, as well as in weeds, and their possible role as reservoirs and transmitters of infection to fruit crops was established. The efficacy of fungicides: Luna Tranquiliti, KS; Skor, KE; Medea, ME; Zato, VDG; Horus, VDG; Coside Super, VDG in suppressing Alternaria blight development on apple cultivars of different ripening dates has been compared.

Management of Alternaria blight disease of mustard through biofungicides

Alternaria blight, caused by Alternaria brassicae, is a major disease affecting mustard crops, leading to significant yield losses. Traditional chemical fungicides have been extensively used to manage this disease, but concerns over environmental pollution, development of resistance, and potential health hazards have shifted the focus towards alternative strategies. Biofungicides, derived from natural sources such as microbes, plants, and their products, have emerged as promising alternatives for managing Alternaria blight while ensuring sustainability and minimal environmental impact. The purpose of the present study was the use of biofungicides as a more sustainable alternative for managing Alternaria blight in mustard at Amity University, located in Noida, Uttar Pradesh. The organic treatment included FYM, Neem oil, Trichoderma viride in different combinations. Pusa Sag1 variety was used for the field study. The present findings revealed the significance differences were recorded in different growth stages of mustard among the various treatment tested. It has been found that minimum disease incidence was observed in T5-Trichoderma viride + FYM + Neem oil (3%), followed by T4Trichoderma viride + Neem oil (13%), T3Trichoderma viride (15%), T2Neem oil(28%), T1FYM(28%). Biofungicides holds great promise for sustainable disease control while minimizing environmental risks and promoting agricultural resilience.