Seaweed (known as marine algae) has a tradition of being part of the animal feed in the coastal areas, from ancient times. Seaweeds, are mixed with animal feed, because when consumed alone can have negative impact on animals. Thus, seaweeds are very rich in useful metabolites (pigments, carotenoids, phlorotannins, polyunsaturated fatty acids, agar, alginate and carrageenan) and minerals (iodine, zinc, sodium, calcium, manganese, iron, selenium), being considered as a natural source of additives that can substitute the antibiotic usage in various animals. In this review, we describe the nutritional values of seaweeds and the seaweed effects in the seaweed-based animal feed/supplements.

The seaweed-based biostimulants available in the market are proven to achieve better results than synthetic commercial fertilizers in plant growth parameters. There are many compounds present in seaweeds that are responsible for the plant bioactivities. Seaweed polysaccharides, such as agar, alginate, and carrageenan, make up most of the seaweed biomass and are proven to achieve excellent results in agricultural crops (in poly- and oligosaccharides formula). These types of compounds are reported to improve seed germination and plant vigor, increase the uptake of soil nutrients, and protect plants against several abiotic and biotic stresses such as salinity, drought, temperature, and pathogens. When applied to the soil directly or sprayed on the foliage, seaweed poly- and oligosaccharides can protect plants against pathogens by stimulating a plant to produce secondary metabolites and manage its defense pathways. Therefore, seaweed poly- and oligosaccharides constitute an important source of potential elicitors in plants and have a particular interest for agriculture. Thus, in this review, the focus is on the potential application of these compounds in the agricultural domain: problems, obstacles, and possibilities.

ISHS International Symposium Brassica 97, Xth Crucifer Genetics Workshop THE RELATIONSHIP BETWEEN COTYLEDON AND ADULT PLANT RESISTANCE TO DOWNY MILDEW (PERONOSPORA PARASITICA) IN BRASSICA OLERACEA