The mycorrhization of the rosemary increases the production of interesting substances for the industry

• Rosemary contains active ingredients with therapeutic, aromatic and organoleptic properties.
• Mycorrhization in intensive rosemary crops improves the production of polyphenols.

Rosemary (Rosmarinus officinalis) is a very common plant in Mediterranean environments grown in nurseries for use in the revegetation of degraded soils, in sustainable gardening and for medicinal and culinary uses.

It is an interesting plant since it contains active ingredients with therapeutic, aromatic and organoleptic properties, and for this reason, its cultivation has a pharmacological, nutraceutical and food industry interest. Rosemary leaves contain high concentrations of phenolic acid, flavonoids, essential oils, triterpenic acid and triterpenic alcohol, substances that stimulate the nervous and circulatory systems, as well as show anticancer effects.

The rosemary establishes a symbiosis with fungi of soil that they forms an arbuscular mycorrhizal, in which both the fungus and the plant benefit from this association. This symbiosis occurs naturally and spontaneously in natural ecosystems, but when the rosemary is cultivated in intensive crops without soil, for the association to take place, it must be inoculated with mycorrhizes.

Researchers at IRTA and the University of Barcelona have observed when you do an artificial inoculation with arbuscular mycorrhizal fungi in the intensive rosemary nurseries, the symbiosis also occurs effectively as in nature.

Thus, the mycorrized rosemary grows better (since the fungus helps the plant to capture nutrients), increasing the amount of leaves and, therefore, the amount of polyphenols produced. This mycorrhization also reduces the contribution of fertilizers in the crop.

The fungus and plant symbiosis positively alters the physiology of rosemary and the production of polyphenols. Polyphenols have an interest in their antioxidant properties, and artificial mycorrhization has been shown to increase their synthesis in four of them (ferulic acid, asian acid, carnosol and vaniline).

This improvement obtained by the mycorrhization is very interesting to increase the yields in the productions destined to obtain these compounds for pharmacological or other purposes.

Seró R, Núñez N, Núñez O, Camprubí A, Grases JM, Saurina J, Moyano E & Calvet C. Modified distribution in the polyphenolic profile of Rosemary leaves induced by plant inoculation with an arbuscular mycorrhizal fungus. J Sci Food Agric 99: 2966-2973 (2019)

Credit Photo: Manuela Böhm