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Anti-phytopathogenic activities of macro-algae extracts.

Jiménez E, Dorta F, Medina C, Ramírez A, Ramírez I, Peña-Cortés H - Mar Drugs (2011)

Bottom Line: Aqueous and ethanolic extracts from the red-alga Gracillaria chilensis prevent the growth of Phytophthora cinnamomi, showing a response which depends on doses and collecting-time.Similarly, aqueous and ethanolic extracts from the brown-alga Durvillaea antarctica were able to diminish the damage caused by tobacco mosaic virus (TMV) in tobacco leaves, and the aqueous procedure is, in addition, more effective and seasonally independent.These results suggest that macro-algae contain compounds with different chemical properties which could be considered for controlling specific plant pathogens.

View Article: PubMed Central - PubMed

Affiliation: Biotechnology Center "D. Alkalay L.", Universidad Técnica Federico Santa María, Avda. España 1680, Valparaiso, Chile.

ABSTRACT
Aqueous and ethanolic extracts obtained from nine Chilean marine macro-algae collected at different seasons were examined in vitro and in vivo for properties that reduce the growth of plant pathogens or decrease the injury severity of plant foliar tissues following pathogen infection. Particular crude aqueous or organic extracts showed effects on the growth of pathogenic bacteria whereas others displayed important effects against pathogenic fungi or viruses, either by inhibiting fungal mycelia growth or by reducing the disease symptoms in leaves caused by pathogen challenge. Organic extracts obtained from the brown-alga Lessonia trabeculata inhibited bacterial growth and reduced both the number and size of the necrotic lesion in tomato leaves following infection with Botrytis cinerea. Aqueous and ethanolic extracts from the red-alga Gracillaria chilensis prevent the growth of Phytophthora cinnamomi, showing a response which depends on doses and collecting-time. Similarly, aqueous and ethanolic extracts from the brown-alga Durvillaea antarctica were able to diminish the damage caused by tobacco mosaic virus (TMV) in tobacco leaves, and the aqueous procedure is, in addition, more effective and seasonally independent. These results suggest that macro-algae contain compounds with different chemical properties which could be considered for controlling specific plant pathogens.

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Related in: MedlinePlus

Effect of algae extracts on tomato leaves following infection with Botrytis cinerea. Tomato leaves were used for evaluating the protecting properties of Chilean algae extracts. Control leaves without previous treatment were infected with fungal conidial suspension. Another set of tomato leaves were treated with different concentrations of either aqueous or ethanolic extracts before pathogen challenge as described in Experimental Section. The picture represents an average example of (A) control leaves and (B) leaves treated with commercial fungicide Captan before to B. cinerea infection.
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f3-marinedrugs-09-00739: Effect of algae extracts on tomato leaves following infection with Botrytis cinerea. Tomato leaves were used for evaluating the protecting properties of Chilean algae extracts. Control leaves without previous treatment were infected with fungal conidial suspension. Another set of tomato leaves were treated with different concentrations of either aqueous or ethanolic extracts before pathogen challenge as described in Experimental Section. The picture represents an average example of (A) control leaves and (B) leaves treated with commercial fungicide Captan before to B. cinerea infection.

Mentions: In order to examine whether the extracts have some properties to protect plant leaves against infection with B. cinerea, tomato petioles were solvent treated (Figure 3A) or pre-treated with either aqueous or ethanolic extracts at different concentrations before pathogen challenge (Figure 3B). None of the aqueous extracts from the collected algae caused any reduction in injury severity in leaves after pathogen infection (data not shown). Similar results were obtained with ethanolic extracts (data not shown). However, ethanolic extracts from L. trabeculata collected in three different seasons reduced the damage in tomato leaves caused by B. cinerea infection (Figure 4). Extracts gained from samples collected in seasons 2, 3 and 4 seem to be more efficient in providing the protective effect, resulting in a reduction of both the number and the size of lesions caused following the infection with the pathogen compared to negative control leaves. The protective capacity of these extracts is more effective at 10,000 ppm, reaching a protection grade of 95% in leaves treated with extracts of season 2, 93% with extracts of season 3 and 72% in those treated with extracts of season 4 (Figure 4B). Lower concentrations of the extracts isolated from season 2 and 3 also reduced the damage in tomato leaves, in around 80% compared to the injury observed in negative control leaves (Figure 3B). The results suggest that LT ethanolic extracts contain certain active principle(s) which may provide protection to tomato leaves against the pathogenic fungi B. cinerea in a dose- and seasonal dependent manner.


Anti-phytopathogenic activities of macro-algae extracts.

Jiménez E, Dorta F, Medina C, Ramírez A, Ramírez I, Peña-Cortés H - Mar Drugs (2011)

Effect of algae extracts on tomato leaves following infection with Botrytis cinerea. Tomato leaves were used for evaluating the protecting properties of Chilean algae extracts. Control leaves without previous treatment were infected with fungal conidial suspension. Another set of tomato leaves were treated with different concentrations of either aqueous or ethanolic extracts before pathogen challenge as described in Experimental Section. The picture represents an average example of (A) control leaves and (B) leaves treated with commercial fungicide Captan before to B. cinerea infection.
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC3111179&req=5

f3-marinedrugs-09-00739: Effect of algae extracts on tomato leaves following infection with Botrytis cinerea. Tomato leaves were used for evaluating the protecting properties of Chilean algae extracts. Control leaves without previous treatment were infected with fungal conidial suspension. Another set of tomato leaves were treated with different concentrations of either aqueous or ethanolic extracts before pathogen challenge as described in Experimental Section. The picture represents an average example of (A) control leaves and (B) leaves treated with commercial fungicide Captan before to B. cinerea infection.
Mentions: In order to examine whether the extracts have some properties to protect plant leaves against infection with B. cinerea, tomato petioles were solvent treated (Figure 3A) or pre-treated with either aqueous or ethanolic extracts at different concentrations before pathogen challenge (Figure 3B). None of the aqueous extracts from the collected algae caused any reduction in injury severity in leaves after pathogen infection (data not shown). Similar results were obtained with ethanolic extracts (data not shown). However, ethanolic extracts from L. trabeculata collected in three different seasons reduced the damage in tomato leaves caused by B. cinerea infection (Figure 4). Extracts gained from samples collected in seasons 2, 3 and 4 seem to be more efficient in providing the protective effect, resulting in a reduction of both the number and the size of lesions caused following the infection with the pathogen compared to negative control leaves. The protective capacity of these extracts is more effective at 10,000 ppm, reaching a protection grade of 95% in leaves treated with extracts of season 2, 93% with extracts of season 3 and 72% in those treated with extracts of season 4 (Figure 4B). Lower concentrations of the extracts isolated from season 2 and 3 also reduced the damage in tomato leaves, in around 80% compared to the injury observed in negative control leaves (Figure 3B). The results suggest that LT ethanolic extracts contain certain active principle(s) which may provide protection to tomato leaves against the pathogenic fungi B. cinerea in a dose- and seasonal dependent manner.

Bottom Line: Aqueous and ethanolic extracts from the red-alga Gracillaria chilensis prevent the growth of Phytophthora cinnamomi, showing a response which depends on doses and collecting-time.Similarly, aqueous and ethanolic extracts from the brown-alga Durvillaea antarctica were able to diminish the damage caused by tobacco mosaic virus (TMV) in tobacco leaves, and the aqueous procedure is, in addition, more effective and seasonally independent.These results suggest that macro-algae contain compounds with different chemical properties which could be considered for controlling specific plant pathogens.

View Article: PubMed Central - PubMed

Affiliation: Biotechnology Center "D. Alkalay L.", Universidad Técnica Federico Santa María, Avda. España 1680, Valparaiso, Chile.

ABSTRACT
Aqueous and ethanolic extracts obtained from nine Chilean marine macro-algae collected at different seasons were examined in vitro and in vivo for properties that reduce the growth of plant pathogens or decrease the injury severity of plant foliar tissues following pathogen infection. Particular crude aqueous or organic extracts showed effects on the growth of pathogenic bacteria whereas others displayed important effects against pathogenic fungi or viruses, either by inhibiting fungal mycelia growth or by reducing the disease symptoms in leaves caused by pathogen challenge. Organic extracts obtained from the brown-alga Lessonia trabeculata inhibited bacterial growth and reduced both the number and size of the necrotic lesion in tomato leaves following infection with Botrytis cinerea. Aqueous and ethanolic extracts from the red-alga Gracillaria chilensis prevent the growth of Phytophthora cinnamomi, showing a response which depends on doses and collecting-time. Similarly, aqueous and ethanolic extracts from the brown-alga Durvillaea antarctica were able to diminish the damage caused by tobacco mosaic virus (TMV) in tobacco leaves, and the aqueous procedure is, in addition, more effective and seasonally independent. These results suggest that macro-algae contain compounds with different chemical properties which could be considered for controlling specific plant pathogens.

Show MeSH
Related in: MedlinePlus