Morphological and chemical alterations inBotrytis cinereaexposed to the dicarboximide fungicide vinclozolin

1997 ◽  
Vol 43 (6) ◽  
pp. 552-560 ◽  
Author(s):  
Silvia M. J. C. S. Cabral ◽  
João P. S. Cabral

Treatment of actively growing Botrytis cinerea hyphae with micromolar concentrations of the dicarboximide fungicide vinclozolin resulted in significant alterations in the growth rate, morphology, and chemical composition of the cells. The addition of vinclozolin resulted in an immediate and severe reduction in the hyphal growth rate and a retardation in the emergence of the second germ tube. Cells treated with vinclozolin had a lower content of pool metabolites than control cells, and this difference increased with time of exposure to the fungicide. In contrast, vinclozolin-treated cells had a higher chitin concentration than control cells. These biochemical alterations were followed by the disorganization and clearing of cells, and by the appearance of dense and dark masses outside the hyphae, presumably composed of cell debris. Hyphae exposed to vinclozolin were more curved and branched and had shorter cells than the controls. The results indicate that vinclozolin causes a slow but generalized leakage of pool metabolites; this release precedes cell lysis and is not the result of a rapid and gross damage to the cytoplasmic membrane.Key words: vinclozolin, Botrytis cinerea, pool metabolites, membrane damage.

1978 ◽  
Vol 56 (7) ◽  
pp. 736-741 ◽  
Author(s):  
Hans J. Grambow ◽  
Dietmar Müller

In vitro Puccinia graminis f.sp. tritici, race 32, produced dikaryotic hyphae from infection structures, corresponding to appressoria and substomatal vesicles (differentiated), which are formed by germ tubes as a response to a heat shock within 24 h after seeding the spores. Dikaryotic hyphae also formed spontaneously from nondifferentiated senescing germ tubes 3–4 days after seeding the spores. The hyphae which originated from the different structures did not appear to be different with regard to nuclear condition, morphological appearance, and fluorescence properties as a consequence of Feulgen staining. 3,3′-Bis-indolylmethane (BIM) increased the hyphal growth rate in contrast with the germ tube growth rate. It also supported the transition from germ tube growth to hyphal growth. The possible mode of action of BIM and the involvement of an unknown factor which represses hyphal growth are discussed.


Author(s):  
Josemar Gonçalves de Oliveira Filho ◽  
Guilherme da Cruz Silva ◽  
Aline Cristina de Aguiar ◽  
Lavinia Cipriano ◽  
Henriette Monteiro Cordeiro de Azeredo ◽  
...  

2017 ◽  
Vol 17 (1) ◽  
Author(s):  
Kaile Sun ◽  
Ageeth van Tuinen ◽  
Jan A. L. van Kan ◽  
Anne-Marie A. Wolters ◽  
Evert Jacobsen ◽  
...  

2012 ◽  
Vol 730-732 ◽  
pp. 883-888 ◽  
Author(s):  
Daniel J. Moutinho ◽  
Laércio G. Gomes ◽  
Otávio L. Rocha ◽  
Ivaldo L. Ferreira ◽  
Amauri Garcia

Solidification of ternary Al-Cu-Si alloys begins with the development of a complex dendritic network typified by primary (λ1) and secondary (λ2) dendrite arm spacings which depend on the chemical composition of the alloy and on the casting thermal parameters such as the growth rate and the cooling rate. These thermal parameters control the scale of dendritic arms, the size and distribution of porosity and intermetallic particles in the casting. In this paper, λ1and λ2were correlated with experimental thermal parameters i.e., the tip growth rate and the tip cooling rate. The porosity profile along the casting length has also been experimentally determined. The volumetric fraction of pores increase with the increase in alloying Si and with the increase in Fe concentration at the regions close to the casting cooled surface.


2021 ◽  
pp. 130506
Author(s):  
Yun Zhao ◽  
Yun-Hai Yang ◽  
Min Ye ◽  
Kai-Bo Wang ◽  
Li-Ming Fan ◽  
...  

2001 ◽  
Vol 41 (5) ◽  
pp. 697 ◽  
Author(s):  
D. R. Beasley ◽  
D. C. Joyce ◽  
L. M. Coates ◽  
A. H. Wearing

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.


2018 ◽  
Vol 16 (02) ◽  
pp. 15-24
Author(s):  
Zaker M ◽  
Zaker L

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


2006 ◽  
Vol 12 (2) ◽  
pp. 157-163 ◽  
Author(s):  
C. SOLBERG ◽  
L. WILLUMSEN ◽  
S. AMBLE ◽  
T. JOHANESSEN ◽  
H. SVEIER

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