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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 the infection symptoms in tobacco leaves caused by tobacco mosaic virus (TMV). In vivo assays using tobacco leaves were performed to determine the influence of macroalgae extracts on tobacco leaves challenged with TMV. Therefore, (A) non-treated tobacco leaves or (B) treated ones with solutions containing different amounts of D. antarctica extracts were subsequently infected with TMV. Damage symptoms were evaluated as described in Experimental Section.
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f5-marinedrugs-09-00739: Effect of algae extracts on the infection symptoms in tobacco leaves caused by tobacco mosaic virus (TMV). In vivo assays using tobacco leaves were performed to determine the influence of macroalgae extracts on tobacco leaves challenged with TMV. Therefore, (A) non-treated tobacco leaves or (B) treated ones with solutions containing different amounts of D. antarctica extracts were subsequently infected with TMV. Damage symptoms were evaluated as described in Experimental Section.

Mentions: Most of the extracts obtained from Chilean algae under the experimental conditions did not show a protecting effect on tobacco leaves from damage caused following TMV infection (data not shown). Nevertheless, both extracting conditions provided crude extracts from the alga Durvillea antarctica which reduced the damage symptoms in tobacco leaves produced following TMV challenge. The protecting effect presented by both extracts led to a reduction of the number and the size of necrotic lesions (Figure 5A,B). This effect resulted in all aqueous or ethanolic extracts when 5000 and 10,000 ppm were applied independently of collecting time. The reduction of the injury severity caused following TMV infection was higher than 90% compared to those detected in the negative controls (Figure 6A,B). The protective effect provided by the extracts is superior to those obtained by applying the commercial antiviral Ribavirin. The protective effect decreased with lower concentrations, the lowest one being found in ethanolic extracts from seasons 3 and 4 (Figure 6B). The most important protective effect was observed by applying extracts from season 1 or season 2 independently of the extracting procedure. Both extracts are active even at amounts of 1000 ppm and the disease symptoms are more severely reduced by applying extracts obtained from algae collected in season 1 (Figure 6A,B). Application of 100 ppm already reduces necrotic lesions (Figure 7A) in infected leaves, reaching a protective result of 95% compared to the negative control at concentrations of 500 ppm (Figure 7B).


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 the infection symptoms in tobacco leaves caused by tobacco mosaic virus (TMV). In vivo assays using tobacco leaves were performed to determine the influence of macroalgae extracts on tobacco leaves challenged with TMV. Therefore, (A) non-treated tobacco leaves or (B) treated ones with solutions containing different amounts of D. antarctica extracts were subsequently infected with TMV. Damage symptoms were evaluated as described in Experimental Section.
© Copyright Policy - open-access
Related In: Results  -  Collection

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

f5-marinedrugs-09-00739: Effect of algae extracts on the infection symptoms in tobacco leaves caused by tobacco mosaic virus (TMV). In vivo assays using tobacco leaves were performed to determine the influence of macroalgae extracts on tobacco leaves challenged with TMV. Therefore, (A) non-treated tobacco leaves or (B) treated ones with solutions containing different amounts of D. antarctica extracts were subsequently infected with TMV. Damage symptoms were evaluated as described in Experimental Section.
Mentions: Most of the extracts obtained from Chilean algae under the experimental conditions did not show a protecting effect on tobacco leaves from damage caused following TMV infection (data not shown). Nevertheless, both extracting conditions provided crude extracts from the alga Durvillea antarctica which reduced the damage symptoms in tobacco leaves produced following TMV challenge. The protecting effect presented by both extracts led to a reduction of the number and the size of necrotic lesions (Figure 5A,B). This effect resulted in all aqueous or ethanolic extracts when 5000 and 10,000 ppm were applied independently of collecting time. The reduction of the injury severity caused following TMV infection was higher than 90% compared to those detected in the negative controls (Figure 6A,B). The protective effect provided by the extracts is superior to those obtained by applying the commercial antiviral Ribavirin. The protective effect decreased with lower concentrations, the lowest one being found in ethanolic extracts from seasons 3 and 4 (Figure 6B). The most important protective effect was observed by applying extracts from season 1 or season 2 independently of the extracting procedure. Both extracts are active even at amounts of 1000 ppm and the disease symptoms are more severely reduced by applying extracts obtained from algae collected in season 1 (Figure 6A,B). Application of 100 ppm already reduces necrotic lesions (Figure 7A) in infected leaves, reaching a protective result of 95% compared to the negative control at concentrations of 500 ppm (Figure 7B).

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