The invention relates to the use of an organo-mineral composition by foliar application to stimulate plant development in the presence of at least one abiotic stress, said composition comprising the following compounds:

TABLE-US-00001 algae extract 5 to 50% soluble silica expressed as SiO.sub.2 0.5 to 2.5% mineral nutrients 0 to 30% trace elements 0 to 12% organic acids 0 to 30%,
the percentages being expressed as weight of dry matter of each of said compounds with respect to the total weight of dry matter of said organo-mineral composition.

The invention relates to the use of an organo-mineral composition by foliar application to stimulate plant development in the presence of at least one abiotic stress, said composition comprising the following compounds:

TABLE-US-00001 algae extract 5 to 50% soluble silica expressed as SiO.sub.2 0.5 to 2.5% mineral nutrients 0 to 30% trace elements 0 to 12% organic acids 0 to 30%,
the percentages being expressed as weight of dry matter of each of said compounds with respect to the total weight of dry matter of said organo-mineral composition.

The invention relates to the use of an organo-mineral composition by foliar application to stimulate plant development in the presence of at least one abiotic stress, said composition comprising the following compounds:

TABLE-US-00001 algae extract 5 to 50% soluble silica expressed as SiO.sub.2 0.5 to 2.5% mineral nutrients 0 to 30% trace elements 0 to 12% organic acids 0 to 30%,
the percentages being expressed as weight of dry matter of each of said compounds with respect to the total weight of dry matter of said organo-mineral composition.

Phlorotannins with anti-viral properties, in particular those with a molecular mass of from about 1000 g/mol to about 3000 g/mol, are described. The phlorotannins may be obtained or obtainable as an extract from seaweed, and may be used in compositions or extracts as anti-viral agents. Methods for producing the extracts and their use for treating or preventing viral infections and for reducing or controlling a virus on a surface using the phlorotannins are also described.

Phlorotannins with anti-viral properties, in particular those with a molecular mass of from about 1000 g/mol to about 3000 g/mol, are described. The phlorotannins may be obtained or obtainable as an extract from seaweed, and may be used in compositions or extracts as anti-viral agents. Methods for producing the extracts and their use for treating or preventing viral infections and for reducing or controlling a virus on a surface using the phlorotannins are also described.

Provided is a component having plant defense activity. A PR1 gene expression activator containing a culture of a unicellular alga containing a green photosynthetic pigment as an active ingredient; A plant defense activator containing a culture of a unicellular alga containing a green photosynthetic pigment as an active ingredient; A plant disease preventive or ameliorating agent containing a culture of a unicellular alga containing a green photosynthetic pigment as an active ingredient; and a method of producing a plant defense activating component containing: cultivating a unicellular alga containing a green photosynthetic pigment under an aerobic condition to produce a culture containing an extracellular polysaccharide.

Provided is a component having plant defense activity. A PR1 gene expression activator containing a culture of a unicellular alga containing a green photosynthetic pigment as an active ingredient; A plant defense activator containing a culture of a unicellular alga containing a green photosynthetic pigment as an active ingredient; A plant disease preventive or ameliorating agent containing a culture of a unicellular alga containing a green photosynthetic pigment as an active ingredient; and a method of producing a plant defense activating component containing: cultivating a unicellular alga containing a green photosynthetic pigment under an aerobic condition to produce a culture containing an extracellular polysaccharide.

Provided is a component having plant defense activity. A PR1 gene expression activator containing a culture of a unicellular alga containing a green photosynthetic pigment as an active ingredient; A plant defense activator containing a culture of a unicellular alga containing a green photosynthetic pigment as an active ingredient; A plant disease preventive or ameliorating agent containing a culture of a unicellular alga containing a green photosynthetic pigment as an active ingredient; and a method of producing a plant defense activating component containing: cultivating a unicellular alga containing a green photosynthetic pigment under an aerobic condition to produce a culture containing an extracellular polysaccharide.

The present invention relates to a concentrated algal extract having a percentage dry matter of between 6 and 100%, the preparation process thereof and also the uses thereof alone or combined with another nutritive, biostimulating or plant-protecting technology, especially to promote plant emergence, growth, development and reproduction and to prevent birds from eating the seeds. The invention also targets a process for applying the concentrated algal extract of the present invention, and also a seed coated with said extract.

The present invention relates to a concentrated algal extract having a percentage dry matter of between 6 and 100%, the preparation process thereof and also the uses thereof alone or combined with another nutritive, biostimulating or plant-protecting technology, especially to promote plant emergence, growth, development and reproduction and to prevent birds from eating the seeds. The invention also targets a process for applying the concentrated algal extract of the present invention, and also a seed coated with said extract.