POLYHEALTH A.E<\/strong>. and the research team of the University of Thessaly, have shown that the synergy of antimicrobials acts as an important tool to increase their effectiveness. For this purpose, in the framework of WP 3, the effectiveness of new synergistic mixtures will be evaluated as possible field pesticides, as well as food and cosmetics preservatives.<\/p>\nTherefore, in the framework of WP 3, the following will be evaluated and optimized with research: i) the in-vitro<\/em> and in-vivo<\/em> effectiveness of the liquid mixtures of olive polyphenols\/pomegranate juice extracts and\/or oranges as natural pesticides against phytopathogens (subsection of the WP 3.1) and ii) the effectiveness of the produced encapsulated powder mixtures of olive polyphenol extract\/pomegranate juice extraction residues and\/or oranges as natural in-vitro<\/em> and in-vivo<\/em> preservatives against pathogenic microorganisms of foods and cosmetics (subsection of the WP 3.2). In both cases, the in vitro<\/em> studies will precede the in vivo<\/em> ones in order to focus the research on the most effective mixtures, limiting the number of final treatments.[\/vc_column_text][vc_empty_space][vc_column_text]<\/p>\nWP 3.1. In-vitro<\/em><\/strong> and in-vivo<\/em> studies of liquid mixtures as pesticides against root and foliar pathogenic microorganisms<\/strong><\/h3>\nThe in<\/em>–<\/em>vitro<\/em> tests will be performed with different methods so that there will be reliability and the possibility of drawing as safe conclusions as possible:<\/p>\n\n- By studying the inhibition zones by the method of wells or paper trays, where after coating the target microorganism on a suitable solid medium (eg nutrient agar for bacteria, potato dextrose agar for yeasts)the liquid antimicrobial (liquid mixture of olive polyphenol extracts and pomegranate and\/or orange juice residues) will be placed in the center of the plate and the incubation zone (mm) around the antimicrobial after incubation will be measured.<\/li>\n
- By studying the MIC-Minimum Inhibitory Concentration (MIC) and the Minimum Lethal Concentration (MLC) on a suitable liquid growth medium (eg nutrient broth for bacteria, potato dextrose broth for fungal yeasts)with increasing concentration of liquid antimicrobial substance.<\/li>\n<\/ul>\n
Specifically, the effectiveness against phytopathogenic microorganisms will be studied, especially soil and foliar phytopathogenic fungi such as Verticillium dahliae<\/em>, Fusarium<\/em> oxysporum<\/em>, Botrytis cinerea<\/em>, Rhizoctonia solani<\/em>, Eutypa lata<\/em>, Monilia laxa<\/em>, Pyrenochaeta lycopersici<\/em>, Phoma punicae<\/em>, Aspergillus niger <\/em>and Gaumanomyces graminis<\/em>.<\/p>\nFollowing the completion of the in vitro<\/em> evaluation of the extract mixtures, the most effective mixtures for each phytopathogenic microorganism will be selected for further evaluation in order to limit the treatment number of the in vivo <\/em>experiments.<\/p>\nFor the in vivo<\/em> evaluation of the effectiveness of the selected mixtures of olive polyphenol extracts and pomegranate and\/or orange juice residues against phytopathogenic fungi (to be inoculated in tomato plants), the effect of fungi on the growth of tomato plants will be evaluated. Especially, the ability of the polyphenol mixtures to reduce the growth and activity of phytopathogenic fungi will be evaluated by measurements on height, fresh and dry weight of the aboveground and underground parts, as well as the number of flowers and fruits of the tomato plants. The aim of the experiment will be to determine the most effective mixture that, at the same time, will not be phytotoxic to the crop.<\/p>\nAn important aim of this subsection is to propose one (or more) of the co-produced liquid mixtures as an optimal natural pesticide for controlling soil phytopathogens and one (or more) as an optimal natural pesticide for controlling foliage phytopathogens.<\/strong><\/p>\nACTIONS WITHIN THE WORKING PACKAGE AND RESULTS<\/h2>\n
In the first phase of the study, the in vitro<\/em> (Petri-dishes experiment) antimicrobial activity of polyphenols against important phytopathogenic fungi, such as Verticillium dahliae<\/em> and Fusarium oxysporum<\/em>, which cause adromycosis disease on tomato and Botrytis cinerea<\/em>, which causes leaves and fruits post-harvest rot, has been evaluated. In addition, their action against the phytopathogenic fungi Rhizoctonia solani<\/em>, Eutypa lata<\/em>, Monilia laxa<\/em>, Pyrenochaeta<\/em> lycopersici<\/em>, Phoma punicae<\/em>, Aspergillus niger<\/em> and Gaumanomyces graminis<\/em> has been evaluated. All the fungi species used came from a collection of the Benakeio Phytopathological Institute.<\/p>\nThe following techniques were used to evaluate the antimicrobial activity of the produced polyphenols against important phytopathogenic fungi species:<\/p>\n
\n- Measurement of suspension zones (well diffusion assay)<\/li>\n
- Mycelium spread rate in Petri dishes<\/li>\n<\/ul>\n
in order to determine the minimum effect of different concentrations and combinations of 72 extracts of olive, pomegranate and orange polyphenols.<\/p>\n
A segment of the mycelial tissues from the original medium (PDA plates) was placed in test tubes containing a sloping PDA medium and refrigerated at 3 \u03bf<\/sup>C for longer storage. The experiments and the evaluation of the activity of the olive mill waste polyphenol treatments were performed using sections and fungal spores from this material.<\/p>\nIn the second phase of the study, the efficacy of the 11 most effective polyphenol extracts (as obtained from the laboratory experiment) against four of major phytopathogenic fungi species (Verticillium dahliae<\/em>, Rhizoctonia solani<\/em>, Pyrenochaeta lycopersici<\/em> and Botrytis cinerea<\/em>) was evaluated in vivo<\/em> (greenhouse conditions). The extracts were applied on 15-day-old tomato plants (3-leaves growth stage) of variety Bella Dona.<\/p>\nIn the greenhouse experiment, the height of the tomato plants, the fresh and dry weight of the aboveground and underground parts of the plants, as well as the number of flowers and fruits were evaluated.<\/p>\n
The results of the laboratory experiment (in vitro<\/em>) showed that the olive polyphenol extract, as well as its mixtures with a small percentage of orange or pomegranate extracts significantly reduced (up to 100%) the growth of the phytopathogenic fungi Botrytis cinerea<\/em>, Verticillium<\/em> dahliae<\/em>, Rhizoctonia <\/em>solani<\/em>, Eutypa lata<\/em>, Monilia laxa<\/em>, Pyrenochaeta lycopersici<\/em> and Phoma<\/em> punicae<\/em>. However, the extracts evaluated did not significantly reduce the growth of the phytopathogenic fungi Fusarium oxysporum<\/em>, Aspergillus niger<\/em> and Gaumanomyces graminis<\/em>.<\/p>\nThe results of the greenhouse experiment (in vivo<\/em>) showed that the extracts were moderately to very effective against the four tested phytopathogenic fungi. In particular, the mixture containing the olive:pomegranate:orange extracts in a ratio of 80:12:8 caused significant reduction of the four fungi infection, with the result that the growth of the infected tomato plants was similar with that of the uninfected control plants.<\/p>\nThe above results are very encouraging and show the potential of olive, pomegranate and orange polyphenol extracts to be developed in the future into effective natural pesticides.[\/vc_column_text][vc_empty_space][\/vc_column][\/vc_row][vc_row full_width=”stretch_row” css=”.vc_custom_1617973547287{padding-bottom: 40px !important;background-color: #f7f7f7 !important;}”][vc_column][vc_column_text]<\/p>\n
STATE OF EXECUTION OF THE WP 3.1<\/h2>\n
The WP 3.1 has been successfully completed and its deliverables are available.
\n[\/vc_column_text][\/vc_column][vc_column width=”1\/2″][vc_column_text]<\/p>\n
WP 3.1<\/u><\/em><\/strong><\/h4>\nOne report regarding the experimental results, conclusions and proposals of the study entitled: “Study of the effectiveness of the produced liquid mixtures in-vitro and in-vivo as natural pesticides against root and foliar pathogenic microorganisms” (50-to 150 pages). AVAILABLE: 2 TECHNICAL REPORTS (268 AND 136 PAGES, RESPECTIVELY).
\n[\/vc_column_text][\/vc_column][vc_column width=”1\/2″][vc_column_text]<\/p>\n
WP 3.3<\/u><\/em><\/strong><\/h4>\nOne publication in approved international journal concerning the in-vitro and in-vivo effectiveness of the liquid mixtures produced pesticides against root and foliar pathogenic microorganisms. AVAILABLE: TWO PAPERS HAVE BEEN PUBLISHED IN AN APPROVED INTERNATIONAL JOURNAL.
\n[\/vc_column_text][\/vc_column][\/vc_row]<\/p>\n","protected":false},"excerpt":{"rendered":"
[vc_row css=”.vc_custom_1612532606677{margin-bottom: 40px !important;}”][vc_column width=”1\/4″ css=”.vc_custom_1611910168649{background-color: #f7f7f7 !important;}”][vc_custom_heading text=”Project Title” use_theme_fonts=”yes” css=”.vc_custom_1617979266337{padding-top: 15px !important;padding-right: 15px !important;padding-bottom: 15px !important;padding-left: 15px !important;}” el_class=”box-header”][vc_separator color=”custom” border_width=”2″ accent_color=”#c6d3e3″][vc_column_text css=”.vc_custom_1617979298937{margin-top: 10px !important;margin-bottom: 10px !important;}”] Study and optimization of the effectiveness of encapsulated powder mixtures produced as natural food preservatives and liquid mixtures as natural pesticides [\/vc_column_text][vc_separator color=”custom” border_width=”2″ accent_color=”#c6d3e3″][vc_column_text el_class=”wp-duration”]Duration: […]<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":0,"menu_order":130,"comment_status":"closed","ping_status":"closed","template":"","meta":[],"_links":{"self":[{"href":"https:\/\/polyeconatural.gr\/en\/wp-json\/wp\/v2\/pages\/2443"}],"collection":[{"href":"https:\/\/polyeconatural.gr\/en\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/polyeconatural.gr\/en\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/polyeconatural.gr\/en\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/polyeconatural.gr\/en\/wp-json\/wp\/v2\/comments?post=2443"}],"version-history":[{"count":6,"href":"https:\/\/polyeconatural.gr\/en\/wp-json\/wp\/v2\/pages\/2443\/revisions"}],"predecessor-version":[{"id":2449,"href":"https:\/\/polyeconatural.gr\/en\/wp-json\/wp\/v2\/pages\/2443\/revisions\/2449"}],"wp:attachment":[{"href":"https:\/\/polyeconatural.gr\/en\/wp-json\/wp\/v2\/media?parent=2443"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}