scholarly journals Colletotrichum spp: SENSIBILIDADE À FUNGICIDAS E REAÇÃO À CULTIVARES DE SOJA

Nativa ◽  
2021 ◽  
Vol 9 (3) ◽  
pp. 273-280
Author(s):  
Sylvia Raquel Gomes Moraes ◽  
Jaqueline Bezerra da Silva ◽  
Solange Maria Bonaldo ◽  
Wesley Dantas de Souza
Keyword(s):  
Glycine Max ◽  
Mycelial Growth ◽  
Disease Incidence ◽  
Damping Off ◽  
Mato Grosso ◽  
Soybean Cultivars ◽  
Progress Curve ◽  
Significant Yield ◽  
Colletotrichum Spp

Antracnose é uma das doenças economicamente mais importantes da soja e de difícil controle no Mato Grosso, causando perdas significativas de produtividade. Objetivo foi verificar a sensibilidade de fungicidas e reação de cultivares de soja a 30 isolados de Colletotrichum. A ação de sete fungicidas (azoxistrobina + ciproconazol, piraclostrobina + epoxiconazol, trifloxistrobina + protioconazol, piraclostrobina, carbendazim, fluxpiroxada + piraclostrobina e azoxistrobina) foi avaliada medindo o crescimento micelial in vitro. Todos os fungicidas afetaram o crescimento micelial, mas piraclostrobina + epoxiconazol e piraclostrobina foram os mais eficientes. Além disso, 6 cultivares foram inoculadas com 27 isolados para análise de tombamento pré e pós-emergência, incidência e severidade da doença. Os dados de incidência e severidade foram submetidos à fórmula da Área Abaixo da Curva de Progresso da Doença. Interação significativa foi observada entre isolados e cultivares em todas as variáveis. Os isolados IT-4, IT-6, LU-3, MT-1, NU-5, PN-1, QU-2, SO-6, SO-11 e VR-1 apresentaram maior tombamento e AACPD. Exceto QU-2 todos os isolados apresentam conídios falcados. As cultivares 8866, 1179 e 9144 apresentaram menor incidência e severidade da doença. Palavras-chave: Glycine max; tombamento; incidência; severidade; antracnose.   Colletotrichum spp.: Sensibility to fungicides and reaction of commercial germoplasm of soybean   ABSTRACT: Anthracnose is one of the most economically important disease of soybean and difficult to control at Mato Grosso State, causing significant yield losses. Objective was to verify the fungicides sensitivity and soybean cultivars reaction to 30 isolates of Colletotrichum. The action of seven fungicides (azoxystrobin+cyproconazole, pyraclostrobin+epoxiconazole, trifloxystrobin+protioconazole, pyraclostrobin, carbendazim, fluxpyroxade+pyraclostrobin and azoxystrobin) was evaluated measuring in vitro mycelial growth. All fungicides affected the mycelial growth development, but pyraclostrobin + epoxiconazole and pyraclostrobin were the most efficient. Besides, 6 soybean cultivars were inoculated with 27 isolates to analyze pre and post-emergence damping-off, disease incidence and severity. Incidence and severity data were submitted to the formula Area Under the Disease Progress Curve. Significant interaction was observed between isolates and cultivars in all variables. Isolates IT-4, IT-6, LU-3, MT-1, NU-5, PN-1, QU-2, SO-6, SO-11 and VR-1 showed higher damping-off and AUDPC. Excepting the QU-2, all isolates have falcate conidia. Cultivars 8866, 1179 and 9144 presented the lowest disease severity and incidence. Keywords: Glycine max; damping-off; incidence; severity; anthracnose.

scholarly journals Cotton resistance to ramulose and variability of Colletotrichum gossypii f. sp. cephalosporioides

2006 ◽  
Vol 32 (1) ◽  
pp. 9-15 ◽  
Author(s):  
Jefferson Fernandes do Nascimento ◽  
Laércio Zambolim ◽  
Francisco Xavier Ribeiro do Vale ◽  
Paulo Geraldo Berger ◽  
Paulo Roberto Cecon
Keyword(s):  
Disease Severity ◽  
Disease Incidence ◽  
Disease Index ◽  
Mato Grosso ◽  
Progress Curve ◽  
Commercial Cultivars ◽  
Resistant Group ◽  
The Relationship ◽  
Highly Virulent ◽  
Susceptible Group

Four cultivars and 21 lines of cotton were evaluated for resistance to ramulose (Colletotrichum gossypii f. sp. cephalosporioides) in a field where the disease is endemic. The seeds of each genotype were planted in 5 x 5 m plots with three replications. The lines CNPA 94-101 and 'CNPA Precoce 2'were used as standard susceptible and resistant references, respectively. The disease incidence (DI) was calculated from the proportion of diseased plants in the plot. The disease index (DIn) was calculated from the disease severity using a 1 to 9 scale, and was evaluated at weekly intervals starting 107 days after emergence. The data collected was used to calculate the area under disease progress curve (AUDPC). In general, the DIn increased linearly with time and varied from 20.0 to 57.1 and AUDPC from 567 to 1627 among the genotypes which could be clustered in to two distinct groups. The susceptible group contained two cultivars and nine lines and the resistant group contained one cultivar and 12 lines. The relationship between disease index and evaluation times was linear for the 25 genotypes tested. The line CNPA 94-101, used as susceptible standard, was the most susceptible with an average DI = 83.4, DIn = 57.1 and AUDPC = 1627.7. The line CNPA 96-08 with DI = 37.8, DIn = 20.0 and AUDPC = 567.7 was the most resistant one. Among the commercial cultivars 'IAC 22' was the most susceptible and 'CNPA Precoce 2', used as resistant standard was the most resistant. The variability in virulence of the pathogen was studied by spray inoculating nine genotypes with conidial suspensions (10(5)/mL) of either of the 10 isolates. The disease severity was evaluated 30 days later using a scale of 1 to 5. The virulence of the isolate was expressed by DIn. All the isolates were highly virulent but their virulence avaried for several genotypes and could be clustered in two distinct groups of less and more virulent isolates. The isolate MTRM 14 from Mato Grosso was the least virulent while Minas Gerais was the most virulent, with DIn of 6.36 and 46.47, respectively. In this experiment the line HR 102 and the cultivar 'Antares' were the most resistant ones with DIns of 18.32 and 19.14, respectively.

VARIABILITY IN SENSITIVITY TO THE FUNGICIDE PYROXYCHLOR WITHIN THE GENERA PHYTOPHTHORA AND PYTHIUM

1976 ◽  
Vol 56 (2) ◽  
pp. 365-369 ◽  
Author(s):  
LLOYD T. RICHARDSON
Keyword(s):  
Mycelial Growth ◽  
The Other ◽  
Individual Species ◽  
Systemic Fungicide ◽  
Damping Off ◽  
Response Curves ◽  
In Vitro Sensitivity ◽  
Pea Seedlings ◽  
Growth Room

A comparative study was made of the innate sensitivity of individual species within the genera Phytophthora and Pythium to the selective systemic fungicide pyroxychlor (2-chloro-6-methoxy-4-(Trichloromethyl)pyridine). In vitro sensitivity was evaluated on the basis of inhibition of mycelial growth on treated V8-juice agar. Little variation was found among the 10 Phytophtora spp. tested, the dosage response curves being linear and generally steep, with ED50 values ranging from 0.4 to 6.2 ppm. Similar steep, linear curves with low ED50 values were obtained with six Pythium spp., but five other species responded quite differently. P. sylvaticum was the most tolerant with no inhibition up to 25 ppm and only 20% at 100 ppm. The dosage response of the other species was irregular. Inhibition of P. irregulare and P. splendens reached a maximum of 50% near 1 ppm. The curve for P. ultimum also reached a maximum near 1 pp, but declined to a lower, constant level. The curve for P. polymastum was distinctly bimodal, ascending with dosage up to 0.5 ppm, descending sharply to 3.1 ppm, then ascending again. The effectiveness of pyroxychlor in controlling preemergence damping-off of pea seedlings caused by four of the Pythium spp. was compared in a growth-room test. P. aphanidermatum and P. ultimum were effectively controlled by postplant drench treatments, but P. irregulare and P. sylvaticum were not.

scholarly journals Control of Sphaeropsis Rot in Stored Apple Fruit Caused by Sphaeropsis pyriputrescens with Postharvest Fungicides

Plant Disease ◽  
2011 ◽  
Vol 95 (9) ◽  
pp. 1075-1079 ◽  
Author(s):  
C. L. Xiao ◽  
Y. K. Kim ◽  
R. J. Boal
Keyword(s):  
Mycelial Growth ◽  
Disease Incidence ◽  
Apple Fruit ◽  
Conidial Germination ◽  
Fruit Rot ◽  
Mitigation Measures ◽  
The Mean ◽  
Rot Disease ◽  
Sphaeropsis Rot

Sphaeropsis rot caused by Sphaeropsis pyriputrescens is a recently reported postharvest fruit rot disease of apple grown in Washington State. The objective of this study was to develop chemical-based mitigation measures for Sphaeropsis rot in stored apple fruit. To determine in vitro sensitivity of S. pyriputrescens to the three registered postharvest fungicides thiabendazole, fludioxonil, and pyrimethanil, 30 isolates of S. pyriputrescens obtained from various sources were tested for mycelial growth and conidial germination on fungicide-amended media. Golden Delicious apple fruit were inoculated with the pathogen in the orchard at 2 or 5 weeks before harvest. After harvest, fruit were either nontreated or dipped in thiabendazole, fludioxonil, or pyrimethanil solutions, stored at 0°C, and monitored for decay development for up to 9 months after harvest. The mean effective concentration of a fungicide that inhibits mycelial growth or spore germination by 50% relative to the nonamended control (EC50) values of thiabendazole, fludioxonil, and pyrimethanil on mycelial growth were 0.791, 0.0005, and 2.829 μg/ml, respectively. Fludioxonil and pyrimethanil also were effective in inhibiting conidial germination of the fungus with EC50 values of 0.02 μg/ml for fludioxonil and 5.626 μg/ml for pyrimethanil. All three postharvest fungicides applied at label rates immediately after harvest were equally effective in controlling Sphaeropsis rot in stored apple fruit, reducing disease incidence by 92 to 100% compared with the nontreated control. The results indicated that Sphaeropsis rot may be effectively controlled by the currently registered postharvest fungicides thiabendazole, fludioxonil, and pyrimethanil.

scholarly journals VARIATION IN AGGRESSIVENESS OF FUSARIUM HEAD BLIGHT SPECIES TOWARDS BARLEY PLANTS DETERMINED USING THREE IN VITRO ASSAYS

2019 ◽  
Vol 31 (1) ◽  
pp. 19-33 ◽  
Author(s):  
Nachaat Sakr
Keyword(s):  
Fusarium Head Blight ◽  
Disease Incidence ◽  
Germination Rate ◽  
Field Conditions ◽  
In Vitro Assays ◽  
Lesion Length ◽  
Head Blight ◽  
Coleoptile Length ◽  
Progress Curve

Aggressiveness is the most important fungal trait affecting Fusarium head blight (FHB) disease invasion and stability of host resistance. Until recently, in vitro methodologies have proved to be very useful in analyzing disease responses in barley plants to FHB infection. To update our knowledge, the variation in aggressiveness for 16 isolates of four FHB species was assessed towards two barley cultivars varying in resistance to FHB. Nine aggressiveness criteria involved in three in vitro assays were used: incubation period, latent period (LP), lesion length (of detached leaf and clip-dipping inoculations), germination rate reduction, standardized area under disease progress curve (AUDPCstandard), coleoptile length reduction of Petri-dish inoculation, and percentage of infected seedlings (of foliar-spraying and pin-point inoculations). Differences in inoculated treatment were observed on young plant parts relative to water controls. Inter and intraspecific differences in aggressiveness were observed towards barley plants as measured by LP and AUDPCstandard. Nevertheless, the other seven criteria did not differentiate FHB isolates. Results indicted that a cultivar-specific aggressiveness do not exist among barley plants and pathogens for LP and AUDPCstandard. Significant correlation coefficients were obtained between the data of LP and AUDPCstandard. Moreover, the values of LP and AUDPCstandard were significantly correlated with the data of disease incidence generated under controlled and field conditions. It seems that LP and AUDPCstandard are indicators of aggressiveness occurring in the whole plant during FHB infection. To our best knowledge, this is the first in vitro research full analyzing aggressiveness of four FHB species on barley plants. In addition, our study investigates the potential use of in vitro indices in predicting FHB data generated under controlled and field conditions.

scholarly journals POTENTIAL OF PLANT EXTRACTS AND FUNGICIDES FOR MANAGING FUSARIUM OXYSPORUM F. SPLYCOPERSICI

2018 ◽  
Vol 30 (1) ◽  
pp. 75 ◽  
Author(s):  
Gul B. Poussio ◽  
Manzoor A. Abro ◽  
Jamal U. D. Hajano ◽  
Muhammad I. Khaskheli ◽  
Khalid I. Rajput ◽  
...  
Keyword(s):  
Fusarium Oxysporum ◽  
Mycelial Growth ◽  
Disease Incidence ◽  
Block Design ◽  
Fungal Growth ◽  
Tomato Crop ◽  
Randomized Block Design ◽  
Sindh Province ◽  
Causal Fungus

Fusarium oxysporum f.sp. lycopersici (FOL) is a highly destructive fungal pathogen of tomato crop causing wilt disease which may reduce 10 to 90% yield. In Pakistan, tomato is widely grown in Sindh province, major territories are district Hyderabad, Tando Allahyar and Mirpurkhas. Thus, surveys of these territories were conducted to record intensity of the disease and confirm etiology. Furthermore, potential of different botanical pesticides and commercially available fungicides were tested to inhibit mycelial growth of the causal fungus. The experiment was laid down with complete randomized block design with three replications. The results showed that the disease was occurring in all locations with the range of 8-47 % incidence. F. oxysporum f.sp. lycopersici was predominantly isolated from the collected disease sample during survey and pathogenic nature of the fungus was tested on the tomato Golo variety through soil drenching method. The disease incidence of 30 and 42 % (72 % as total) was recorded in inoculated tomato plants at 20 and 40 DAI, respectively. Maximum (67 %) inhibition of the fungal growth was found by neem seed extracts at higher dose of 8 % concentration followed by 63 % with neem seeds and Eucalyptus at 6 and 8 %, respectively. Alternatively, the Nativo 75 WG fungicide was found most effective in reducing the redial mycelial growth of target fungus followed by Topsin-M at 1000 ppm where as Aliette and Melodedue fungicides were found least effective under in-vitro conditions.

scholarly journals Salicylic acid in the induction of resistance to beet seedling damping-off and antifungal activity against Fusarium sp., in vitro

2016 ◽  
Vol 37 (1) ◽  
pp. 67 ◽  
Author(s):  
Douglas Junior Bertoncelli ◽  
Sérgio Miguel Mazaro ◽  
Rita De Cacia Dosciatti Serrão Rocha ◽  
Nean Locatelli Dalacosta ◽  
Adriano Lewandowski ◽  
...  
Keyword(s):  
Salicylic Acid ◽  
Antifungal Activity ◽  
Mycelial Growth ◽  
Experimental Unit ◽  
Damping Off ◽  
Potato Dextrose Agar Medium ◽  
Seedling Length ◽  
Fusarium Sp ◽  
And Control

The damping off is the main disease that affects the beet crop during the seedling production. The aim of this study was to evaluate different salicylic acid (SA) concentrations for resistance induction against damping-off in beet seedling and its antifungal activity against Fusarium sp., in vitro condition. Treatment of beet seed was with SA solution by immersion during 5 minutes in the 0.5, 1.0, 1.5 and 2.0 mM concentrations and control (distilled water). It was used four replications with 20 cells by experimental unit. The experiment was carried out for 14 days in cultivate chamber with temperature (23 oC ± 2°C), lighting (12 hours photoperiod) and humidity (70% ± 10%) controlled. After this time, the germination, damping off incidence, seedling length and fresh mass matter weight were evaluated. It was evaluated also in the seedling tissue the phenylalanine ammonia-lyase (PAL), ?-1.3 glucanase and chitinase level enzymes. In the in vitro the SA was putted in PDA (potato-dextrose-agar) medium, where the Fusarium sp. mycelial growth was evaluated. The SA applied for seeds treatment didn’t had effect significant on damping off of beet seedlings, but it induced the activity of ?-1.3 glucanase enzyme, it being this higher in nine times when compared the treatment control. The SA acted in the Fusarium sp. in vitro control with fungitoxic action, suppressed mycelial growth in 28% if compared to control.

scholarly journals In vitro, In vivo and In situ, Effect of Mancozeb 80 WP on Colletotrichum gloeosporioides (Penz.) Penz. and Sacc., Causative Agent of Anthracnose of Cashew (Anacardium occidentale L.) in Chad and Cameroon

2021 ◽  
pp. 1-14
Author(s):  
Ngoh Dooh Jules Patrice ◽  
Deurnaye Placide ◽  
Abdoul Madjerembe ◽  
Mbou T. Pavel Rony ◽  
Djongnang Gabriel ◽  
...  
Keyword(s):  
Radial Growth ◽  
Colletotrichum Gloeosporioides ◽  
Disease Incidence ◽  
Severity Index ◽  
Anacardium Occidentale ◽  
In Vivo Experiments ◽  
Progress Curve ◽  
Cashew Tree

Aims: The aim of this work was to evaluate effect of Mancozeb 80 WP against Colletotrichum gloeosporioides, the agent responsible of anthracnose of cashew tree (Anacardium occidentale  L.). Study Design: The experimental design was in completely randomized blocks with three replications. Place and Duration of Study: in vitro and in vivo experiments were performed in Laboratory of  Department of Biological Sciences, University of Maroua during six months. Field trial was carried out in Kelo, Chad during three months. Methodology: Isolates were obtained from diseased organs (leaves and fruits) from Kélo in Chad and Maroua in Cameroon. The concentrations used in the laboratory were C1 (5 mg/ml), C2 (0.5 mg/ml), C3 (0.05 mg/ml), C4 (0.005 mg/ml), C5 (0.0 mg/ml). Radial growth, sporulation, conidial germination and pathogenicity were used to characterize and evaluate the effect of Mancozeb on the isolates in vitro. The preventive test was performed on three-month-old plants previously treated with Mancozeb. The concentration of 5 g/l was applied to the field and the incidence and severity were used to calculate the AUIPC (Area Under Disease Incidence Progress Curve) and AUSiPC (Area Under Disease Severity Index Progress Curve) curves. Results: Mancozeb reduced radial growth of all isolates at concentrations C1 (5 mg/ml), C2 (0.5 mg/ml) and C3 (0.05 mg/ml). The percentages of inhibition ranged from 50 to 100%. Mancozeb 80 WP completely (100%) inhibited the germination of C. gloeosporioides conidia in vitro. Mancozeb has protected cashew plants in vivo at the concentration C1 (5 mg/ml). AUIPC and AUSiPC were higher on control plants and lower on Mancozeb-treated plants. Conclusion: Mancozeb 80 WP may be associated in integrated pest management strategy against anthracnose.

scholarly journals Fungicide Seed Treatment Effects on Seedling Damping-off of Pumpkin Caused by Phytophthora capsici

Plant Disease ◽  
2003 ◽  
Vol 87 (1) ◽  
pp. 63-68 ◽  
Author(s):  
M. Babadoost ◽  
S. Z. Islam
Keyword(s):  
Seed Germination ◽  
Untreated Control ◽  
Mycelial Growth ◽  
Seed Treatment ◽  
Culture Medium ◽  
Phytophthora Capsici ◽  
Field Trials ◽  
Seedling Vigor ◽  
Damping Off

Apron XL LS (mefenoxam) and Allegiance FL (metalaxyl) were highly inhibitory to growth of mycelium of Phytophthora capsici in vitro. Effective dose (ED50) of mefenoxam and metalaxyl for 50% inhibition of mycelial growth, for all five isolates of P. capsici tested, was 0.98 and 0.99 μg a.i./ml of culture medium, respectively. For mefenoxam at 200 μg a.i./ml, sporangium and zoospore germination were reduced by 92 and 96%, respectively, and 21 and 24%, respectively, for metalaxyl. In greenhouse studies, seed treatment with mefenoxam (0.42 ml of Apron XL LS/kg of seed) and metalaxyl (0.98 ml of Allegiance FL/kg of seed) significantly reduced pre- and post-emergence damping-off of seedlings caused by P. capsici in three pumpkin cultivars (Dickinson, Hybrid-401, and Hybrid-698) tested. Thirty-one days after seeding, at inoculum levels of 0, 90, 600, 1,400, and 4,000 CFU/g of soil, the average seedling stands for mefenoxam treatment were 98.4, 93.8, 88.3, 77.8, and 64.8%; for metalaxyl, 99.1, 85.3, 85.8, 73.5, and 59.3; and for the untreated control, 97.5, 55.2, 45.7, 37.0, and 22.9%, respectively. In field trials, the average seedling stands 35 days after seeding were 76.7, 74.7, and 44.9% for mefenoxam, metalaxyl, and untreated control, respectively. Seed treatment with mefenoxam or metalaxyl did not have any significant effect on either seed germination or seedling vigor.

scholarly journals Antifungal activity against Alternaria solani and control of early blight in tomato by essential oil of bergamot orange

2020 ◽  
pp. 1861-1874
Author(s):  
Camila Hendges ◽  
José Renato Stangarlin ◽  
Márcia de Holanda Nozaki ◽  
Eloisa Lorenzetti ◽  
Odair José Kuhn
Keyword(s):  
Essential Oil ◽  
Mycelial Growth ◽  
Early Blight ◽  
Culture Media ◽  
Alternaria Solani ◽  
Maximum Growth ◽  
Tomato Crop ◽  
Toxic Activity ◽  
Progress Curve

The early blight (caused by the fungus Alternaria solani) results in significant damage to the tomato crop, directly affecting productivity. An alternative to the frequent use of pesticides is the use of essential oils, which can act in defense against phytopathogens. The objective of this work was to evaluate the toxic activity in vitro of the bergamot orange (Citrus aurantium ssp. bergamia) essential oil against A. solani, the control of the early blight, and the activity of defense enzymes in tomatoes treated with this oil and inoculated with A. solani. Mycelial discs of A. solani were added to dishes with V8 culture media to which essential oil at concentrations of 0, 500, 1000, 1500, 2000, and 2500 µL L-1, in addition to a standard fungicide treatment (azoxystrobin + difenoconazole, 200 + 125 g L-1, respectively) was added. The Petri dishes were incubated at 25 °C in the dark. Mycelial growth was evaluated daily for 19 days, when all treatments reached maximum growth. Sporulation analysis was performed thereafter. Tomato plants were treated with bergamot essential oil, 30 days after transplanting, in the concentrations and fungicide mentioned, in the second pair of leaves. After 72 hours, the pathogen was inoculated using a spray bottle, on treated leaves (second pair of leaves) and untreated leaves (third pair of leaves). The area under the disease progress curve (AUDPC) was calculated based on five severity assessments. The activity of peroxidase (POX), polyphenol oxidase (PPO), and phenylalanine ammonia-lyase (PAL) was evaluated in leaves treated with the concentration of 2500 µL L-1 of essential oil. The concentration of 2500 ?L L-1 reduced mycelial growth and sporulation of the pathogen by 68.15% and 29.48%, respectively. In treatments with application of essential oil, lower AUDPC was observed for a concentration of 2500 ?L L-1, which was statistically similar to that observed for fungicide application, both in treated and untreated leaves. A greater activity of PPO, POX, and PAL was found locally and systemically, both in the second and third leaves, at concentration of 2500 ?L L-1. The essential oil of bergamot can be an alternative for the control of early blight in tomato.

Antifungal activity of plant extracts against Colletotrichum musae, the post harvest anthracnose pathogen of banana cv. Martaman

2016 ◽  
Vol 46 (1) ◽  
pp. 2-15 ◽  
Author(s):  
Dawa Dolma Bhutia ◽  
Yeka Zhimo ◽  
Ramen Kole ◽  
Jayanta Saha
Keyword(s):  
Antifungal Activity ◽  
Plant Species ◽  
Plant Extract ◽  
Mycelial Growth ◽  
Disease Incidence ◽  
Leaf Extracts ◽  
Content Type ◽  
Colletotrichum Musae

Purpose – The purpose of this paper was to determine the antifungal activities of different solvent extracts of common plants in vitro and in vivo against banana anthracnose fungus Colletotrichum musae (Berk & M.A. Curtis) Arx, and to investigate its effects on the pathogen and identify the bio active component(s). Design/methodology/approach – Extracts were obtained from leaves, tender shoots, rhizomes, bulbs, seeds and fruits of 42 naturally growing plant species following hot sequential extraction. Preliminary screening of the solvent extracts was done based on the inhibition of radial mycelial growth of C. musae following poison food technique and conidial germination inhibition by cavity slide technique. The selected extracts were assessed for their effect on harvested banana in reducing anthracnose during storage. The active components in the bio-active fractions of plant extract were identified by gas chromatography-mass spectroscopy. Findings – Methanol extracted a larger quantity of material (between 6.9 and 12.5 per cent) than hexane or chloroform, and all its extracts were active against the test pathogen with mycelial growth inhibition ranging from 13.70 to 88.89 per cent. Zingiber officinale rhizome extract as well as Polyalthia longifolia and Clerodendrum inerme leaf extracts exhibited more than 80 per cent inhibition of mycelial growth. Total inhibition of spore germination of C. musae was recorded in Z. officinale and P. longifolia extracts at 0.3 per cent w/v and 0.5 per cent w/v concentration, respectively, while only 68 per cent spore inhibition was recorded in C. inerme at 0.5 per cent w/v concentration. Of the three plant species, Z. officinale had the best antifungal activity (18.0 per cent disease incidence; 2.2 disease severity scale) when banana fruits were dipped in the extract at a concentration of 0.5 per cent w/v at 5 days of storage in ambient condition (80-82 per cent R.H., 27 ± 1°C). The bio-active compounds in the extract of Z. officinale were identified as alpha-curcumene and zingerone. Originality/value – Based on the antifungal activity, plant extract of Z. officinale can be used as an effective alternative to chemicals in controlling anthracnose pathogen in harvested banana.

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