Effect of Legume Extracts on Germination, Seedling Health of Beans (Phaseolus vulgaris L.) and Soil Microorganisms

Application of undecomposed green manure has been reported to cause poor emergence and establishment of common beans in the field. Therefore, to understand the mechanisms’ contributing to the poor crop establishment, the effect of extracts from fresh and decomposed legume green manures on bean seed germination, fungal mycelial growth, spore germination and germ tube elongation were evaluated. The extracts were prepared in either ethanol or distilled water. Data was collected on percentage seed germination, seedling length, mycelial radial growth, spore germination and germ tube elongation. Ethanol extracts from fresh lablab inhibited bean germination by 56%, increased mean germination time to 8 days, and decreased germination index while ethanol extracts of groundnut and beans caused highest inhibition in bean shoot length and reduced biomass. Ethanol extracts from fresh green manures significantly inhibited fungal mycelial growth while the aqueous extracts from beans, groundnuts and soybean had significant level of antifungal activity while aqueous lablab extracts stimulated mycelial. Aqueous extract of lablab and soybean enhanced spore germination by over 70% with more pronounced effect on germ tube length and number of germ tubes by 8.0% and 13% respectively. The study comparatively reveals that the extract of lablab was inhibitory to common bean germination compared to other legume extracts and also stimulated the growth of root rot pathogens that may have resulted in poor establishment of beans.

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Effect of the triazine herbicides Goltix and Igran on germination and growth of Aspergillus fumigatus, Fusarium oxysporum, Helminthosporium oryzae, and Verticillium agaricinum

Canadian Journal of Botany ◽

10.1139/b89-099 ◽

1989 ◽

Vol 67 (3) ◽

pp. 737-741 ◽

Cited By ~ 1

Author(s):

E. E. A. Elwy ◽

M. Osman ◽

T. M. A. Abdel Rahman ◽

I. M. K. Ismail

Keyword(s):

Spore Germination ◽

Radial Growth ◽

Mycelial Growth ◽

Germ Tube ◽

Fungal Species ◽

Tube Length ◽

Liquid Cultures ◽

Germ Tube Length ◽

Helminthosporium Oryzae ◽

Germination And Growth

The effect of two triazines on spore germination, radial growth, and biomass production were studied in A. fumigatus, F. oxysporum, H. oryzae, and V. agaricinum. Igran inhibited spore germination of all species to some extent and at 1000 ppm completely inhibited spore germination in A. fumigatus and F. oxysporum. Goltix inhibited germination of F. oxysporum and H. oryzae, but stimulated germination of A. fumigatus and V. agaricinum. Germ tube length was significantly decreased at high herbicide concentrations. Both derivatives reduced radial growth rate as well as mycelial growth in liquid cultures. The level of inhibition depends on the herbicide, its concentration, and the fungal species.

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Antifungal Efficacy of Plant Oils Containing Thymol and Carvacrol in Controlling Botrytis cinerea, the Causal Agent of Grape (Vitis vinifera) GrayMould

The Agriculturists ◽

10.3329/agric.v16i02.40339 ◽

2018 ◽

Vol 16 (02) ◽

pp. 15-24

Author(s):

Zaker M ◽

Zaker L

Keyword(s):

Essential Oils ◽

Botrytis Cinerea ◽

Spore Germination ◽

Mycelial Growth ◽

Germ Tube ◽

Plant Diseases ◽

Plant Oils ◽

Horticultural Products ◽

Antifungal Efficacy ◽

Germ Tube Elongation

The efficacy of a large number of plant extracts and essential oils in controlling plant diseases has been proven worldwide. Botrytis cinerea has attacked a wide host range causing severe loss in the field and at storage. In this study the antifungal efficacy of essential oils of three medicinal plants namely wild marjoram (Zataria multifolia), wild savory (perennial) (Satureja mutica) and savory (annual) (Satureja hortensis) possessing these compounds at three concentrations: 50, 100 and 200 ppm were evaluated in controlling the mycelial growth, spore germination and germ tube elongation of B. cinerea. All treatments except savory (annual) essential oil at 50 ppm showed significant differences with the control in inhibiting the mycelial growth as well as spore germination and germ tube elongation of B. cinerea (p=0.01). It was also noted that wild marjoram at 100 ppm and wild savory (perennial) essential oils at 200 ppm could completely (100%) inhibit the growth of the fungus. Essential oils from wild marjoram and wild savory had higher antifungal activity than annual savory. Their suitable formulations could be prepared and used as safe alternatives for controlling moulds of horticultural products during storage. The Agriculturists 2018; 16(2) 15-24

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In vitro effect of substrate, temperature and photoperiod on Phakopsora pachyrhizi urediniospore germination and germ tube growth

Summa Phytopathologica ◽

10.1590/0100-5405/1999 ◽

2015 ◽

Vol 41 (2) ◽

pp. 101-106

Author(s):

Marta Maria Casa Blum ◽

Erlei Melo Reis ◽

Francieli Tavares Vieira ◽

Rita Carlini

Keyword(s):

Substrate Temperature ◽

Spore Germination ◽

Leaf Extract ◽

Germ Tube ◽

Tube Growth ◽

Tube Length ◽

Germ Tube Length ◽

Soybean Leaf ◽

Germ Tube Growth

In vitro experiments were conducted to assess the effects of substrate, temperature and time of exposure to temperature and photoperiod on P. pachyrhizi uredospore germination and germ tube growth. The following substrates were tested: water-agar and soybean leaf extract-agar at different leaf concentrations (0.5, 1.0, 2.0 and 4.0 g of leaves and 15g agar/L water), temperatures (10, 15, 20, 25, 30, and 35oC) and times of exposure (1, 2, 3, 4, 5, 6, 7, and 8 hours) to temperature and 12 different photoperiods. The highest germination and germ tube length was found for the soybean leaf extract agar. Maximum P. pachyrhizi uredospore germination was obtained at 21.8 and 22.3°C, and maximum germ tube growth at 21.4 and 22.1°C. The maximum uredospore germination was found at 6.4 hours exposure, while the maximum germ tube length was obtained at 7.7 h exposure. Regarding photoperiod, the maximum spore germination and the maximum uredospore germ tube length were found in the dark. Neither spore germination nor uredospore germ tube growth was completely inhibited by the exposure to continuous light.

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Growth-inhibiting activity of citronella essential oil to multiple fungal plant pathogens

10.1101/860718 ◽

2019 ◽

Author(s):

Mark Angelo O. Balendres ◽

Fe M. Dela Cueva

Keyword(s):

Essential Oil ◽

Growth Inhibition ◽

Spore Germination ◽

Mycelial Growth ◽

Fungal Pathogens ◽

Germ Tube ◽

Plant Pathogens ◽

Field Experiments ◽

Fungal Plant Pathogens ◽

Germ Tube Elongation

AbstractCymbopogon species are among the most reported essential oils with fungitoxic effect. In this study, mycelial growth of Fusarium oxysporum (banana wilt), Colletotrichum gloeosporioides (mango anthracnose), C. falcatum (sugarcane red rot) and Neopestalotiopsis spp. (mango leaf spot) as influenced by varying concentrations of citronella essential oil (CEO) was assessed in in vitro assays. Following growth inhibition test, spore germination and germ tube elongation of C. gloeosporioides were then examined. Mycelial growth of all test fungal pathogens was strongly inhibited by CEO, but variations were observed among fungal species. This growth inhibition activity was caused by the inhibition of spore germination and germ tube elongation as observed in C. gloeosporioides. The findings of this study show the strong growth-inhibitory activity of CEO to multiple fungal pathogens, indicating CEO’s potential as a chemical control approach against these fungal pathogens. Glasshouse and field experiments would establish CEO as one potential alternative to fungicides.

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Antifungal effect of essential oil and different extracts obtained from Nepeta meyeri on Botrytis cinerea

Acta Scientiarum Polonorum Hortorum Cultus ◽

10.24326/asphc.2021.1.11 ◽

2021 ◽

Vol 20 (1) ◽

pp. 111-122

Author(s):

Sinem Karakuş ◽

Ökkeş Atici ◽

Cafer Köse ◽

Deniz Tiryaki

Keyword(s):

Essential Oil ◽

Botrytis Cinerea ◽

Spore Germination ◽

Mycelial Growth ◽

Germ Tube ◽

Rrna Gene ◽

Potato Dextrose Agar Medium ◽

Antifungal Effect ◽

Petri Dishes ◽

Germ Tube Elongation

The study concerns the antifungal effect of the aqueous and methanolic extracts, and the essential oil obtained from the aerial parts of Nepeta meyeri Benth. on Botrytis cinerea Pers. The fungus has been isolated from the infected plants of common grape Karaerik (Vitis vinifera L.) cultivating in vineyards in Üzümlü district, Erzincan (Turkey), and was cultured on potato dextrose agar medium in Petri dishes after the identification by 18S rRNA gene-based PCR assay. The concentrations of extracts from N. meyeri in Petri dishes were 2%, 5% and 10% (w/v) for aqueous extract (AE); 500, 1000 and 1500 ppm (v/v) for methanolic extract (ME), and 0.6, 0.8 and 1 µL for essential oil (EO). After the treatments, mycelial growth, spore germination, and germ tube elongation were determined. Sterile distilled water at the same ratios was used for the control treatment. Thirty-six different compounds were identified in the EO of N. meyeri by GC/MS. The highest antifungal activity has been registered for EO of N. meyeri. The inhibition rates in 1 µL/Petri of the EO were 80.72%, 18%, 38.15% on mycelial growth, spore germination and germ tube elongation, respectively. However, AE and ME of N. meyeri showed diverse effects on the studied parameters of B. cinerea. It is suggested that the favourable concentration of EO from N. meyeri can contribute to the prevention of B. cinerea infection (grey mould) which causes disease in vineyards.

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Interaction of Xanthomonas campestris pv. undulosa or Pseudomonas cepacia with Septoria nodorum in vitro and in vivo

Canadian Journal of Microbiology ◽

10.1139/m82-027 ◽

1982 ◽

Vol 28 (2) ◽

pp. 205-210 ◽

Cited By ~ 1

Author(s):

J. B. Jones ◽

C. W. Roane

Keyword(s):

Spore Germination ◽

Xanthomonas Campestris ◽

Leaf Extract ◽

Germ Tube ◽

Tube Length ◽

Pseudomonas Cepacia ◽

Septoria Nodorum ◽

Germ Tube Length ◽

Wheat Leaf

Xanthomonas campestris pv. undulosa did not inhibit growth or spore germination of Septoria nodorum on wheat leaf extract agar, whereas Pseudomonas cepacia produced a zone of complete inhibition of spore germination up to 17.5 mm and reduced germination up to 5 cm from the bacterial front. Culture filtrates of the two bacteria grown in 'Blueboy' or 'Arthur' wheat leaf extract broth were incorporated into fresh wheat leaf extract broth. These filtrates caused a reduction in growth (dry weight) of S. nodorum compared with growth in unamended extract. Fungal mass was considerably lower in P. cepacia filtrate of 'Arthur' wheat than in the X. campestris pv. undulosa filtrate or the control. The extent of reduction by P. cepacia filtrate suggests an antibiotic effect. In phosphate buffer, X. campestris pv. undulosa reduced spore germination and germ tube length of S. nodorum, while P. cepacia inhibited germination and germ tube growth completely. In vivo, X. campestris pv. undulosa had no effect on spore germination but did reduce germ tube length whereas P. cepacia inhibited both parameters.

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Effects of Water Stress on Botryosphaeria Blight of Pistachio Caused by Botryosphaeria dothidea

Plant Disease ◽

10.1094/pdis.2001.85.7.745 ◽

2001 ◽

Vol 85 (7) ◽

pp. 745-749 ◽

Cited By ~ 47

Author(s):

Zhonghua Ma ◽

David P. Morgan ◽

Themis J. Michailides

Keyword(s):

Water Stress ◽

Drought Stress ◽

Spore Germination ◽

Mycelial Growth ◽

Germ Tube ◽

Management Strategies ◽

Botryosphaeria Dothidea ◽

Predisposing Factor ◽

Germ Tube Elongation ◽

Pistachio Trees

The effects of water potential (Ψ) on spore germination, germ tube elongation, mycelial growth of Botryosphaeria dothidea, and development of Botryosphaeria blight of pistachio caused by this fungus were studied in the laboratory and greenhouse. In laboratory tests, spore germination, germ tube elongation, and mycelial growth of B. dothidea increased as Ψ decreased from 0 to -2.0 MPa and declined as Ψ decreased below -2.0 MPa. Water stress (Ψ < -0.260 MPa) increased the severity of Botryosphaeria blight on young detached pistachio leaves. In greenhouse inoculation experiments, drought-stressed 2-year-old pistachio trees (leaf Ψ < -0.635 MPa) developed more severe Botryosphaeria blight disease than the nonstressed trees (Ψ > -0.485 MPa) in both 1999 and 2000 experiments. In a similar experiment using 1-year-old potted pistachio trees in 2000, withholding water treatments did not cause enough drought stress in pistachio leaves (Ψ > -0.584 MPa) and did not result in higher disease than the nonstressed trees (Ψ = -0.466 MPa). The correlation coefficient between Ψ and disease index for 1999 experiments was 0.954, and for 2000 experiments I and II was 0.981 and 0.939, respectively. These results indicate that drought stress can be a major predisposing factor of pistachio to infection by B. dothidea. Results from this study can be used to better understand the disease outbreaks in California pistachio orchards and to develop integrated management strategies by adjusting irrigation.

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Saprophytic microorganisms with potential for biological control of Botrytis cinerea on Geraldton waxflower flowers

Australian Journal of Experimental Agriculture ◽

10.1071/ea00112 ◽

2001 ◽

Vol 41 (5) ◽

pp. 697 ◽

Cited By ~ 8

Author(s):

D. R. Beasley ◽

D. C. Joyce ◽

L. M. Coates ◽

A. H. Wearing

Keyword(s):

Botrytis Cinerea ◽

Mycelial Growth ◽

Germ Tube ◽

Conidial Germination ◽

Pseudomonas Sp ◽

Trichoderma Spp ◽

Fusarium Sp ◽

Flower Abscission ◽

Germ Tube Elongation

Saprophytic bacteria, yeasts and filamentous fungi were isolated from Geraldton waxflower flowers and screened to identify potential antagonism towards Botrytis cinerea. Isolates from other sources (e.g. avocado) were also tested. Isolates were initially screened in vitro for inhibition of B. cinerea conidial germination, germ tube elongation and mycelial growth. The most antagonistic bacteria, yeasts and fungi were selected for further testing on detached waxflower flowers. Conidia of the pathogen were mixed with conidia or cells of the selected antagonists, co-inoculated onto waxflower flowers, and the flowers were sealed in glass jars and incubated at 20˚C. The number of days required for the pathogen to cause flower abscission was determined. The most antagonistic bacterial isolate, Pseudomonas sp. 677, significantly reduced conidial germination and retarded germ tube elongation of B. cinerea. None of the yeast or fungal isolates tested was found to significantly reduce conidial germination or retard germ tube elongation, but several significantly inhibited growth of B. cinerea. Fusarium sp., Epicoccum sp. and Trichoderma spp. were the most antagonistic of these isolates. Of the isolates tested on waxflower, Pseudomonas sp. 677 was highly antagonistic towards B. cinerea and delayed waxflower abscission by about 3 days. Trichoderma harzianum also significantly delayed flower abscission. However, as with most of the fungal antagonists used, inoculation of waxflower flowers with this isolate resulted in unsightly mycelial growth.

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Inhibitory effect of Pseudomonas spp. on the development of Botrytis cinerea and Penicillium expansum

Plant Protection Science ◽

10.17221/467-pps ◽

2010 ◽

Vol 40 (No. 4) ◽

pp. 128-134 ◽

Cited By ~ 1

Author(s):

H. Bryk ◽

B. Dyki ◽

P. Sobiczewski

Keyword(s):

Botrytis Cinerea ◽

Spore Germination ◽

Germ Tube ◽

Inhibitory Effect ◽

Penicillium Expansum ◽

Bacterial Strains ◽

Liquid Cultures ◽

Pseudomonas Spp ◽

Apple Leaves ◽

Germ Tube Elongation

The influence of antagonistic Pseudomonas spp. on the development of Botrytis cinerea and Penicillium expansum was studied in liquid cultures. Two strains of Pseudomonas spp. (B194 and B224), originally isolated from apple leaves and fruits, respectively, inhibited spore germination and germ tube elongation of B. cinerea or P. expansum. The inhibitory effect depended on the concentration of bacteria in the cultures. After a prolonged time of incubation (48–76 h) lysis and fragmentation of hyphae of both fungi was observed. In some cases the hyphae of B. cinerea developed abnormally if the bacterial strains were present – the hyphal tips were swollen and ball-shaped spore-like structures aggregated in chains were formed.

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