Endophyte screening from Indo-Spanish medicinal plants: Biotechnological green crop protectants

Abstract

Endophytes are microorganisms that live in the intercellular spaces of plant tissues producing bioactive substances that may be involved in the host-endophyte relationship. These microorganisms represent a biotechnological source of bioactive metabolites. As part of our ongoing study of the endophyte potential for the development of biotechnological biopesticides, we carried out the screening of endophytes from medicinal plants belonging to the genera Laurus, Mentha, Artemisia and Thymus present in India and Spain. Our study included the endophyte biodiversity (isolation and identification) of these plants species, the antagonism-based primary selection of isolates for microfermentation and the secondary selection based on their micro-extract activity on selected targets including insect pests, fungal pathogens and root-knot nematodes. From a total of 11 plant species more than 1000 fungal strains were isolated and 700 were selected for microfermentation. In this presentation we will discuss the relative percentage occurrence for each order and the colonization frequency for each fungal species, the antagonistic effects of these isolates against fungal pathogens (Fusarium sp.) and the bioactivity of their microextracts on the target species will be presented. The bio-guided chemical study of a selected strain (Aa22) will be presented.