Seed endophytes of Noccaea caerulescens: community structure, culturable isolates and their use as a seed treatment option in different crop species

Abstract

The microbiome within a plant consists of numerous symbiotic relationships, but it could be argued that the most important relationship is the one within the seed of the plant. Seed endophytes is the term used to refer to the bacteria and fungi that live within the seed. They play a crucial role in germination and crop performance, adapting alongside the plant when unexpected environmental changes occur. The bacteria associated with the seeds of plants are of particular interest is as they can be used as seed treatment options, potentially lowering the need for pesticides and/or fungicide treatment on crop plants. Noccaea caerulescens is a unique plant species, due to its ability to hyperaccumulate zinc, cadmium, and lead. It thrives on marginal land, polluted with metal(loid)s. Because of this, we believed the bacterial seed endophytes of N. caerulescens worthy of further study. This work had three aims: (1) Find out what is the core microbiome of N. caerulescens, (2) Identify if the culturable isolates had any plant-growth promotion (PGP) potential, (3) Determine whether or not seed treatment with seed endophytes of N. caerulescens had any potential to increase germination of different plant species on marginal land polluted with metal(loid)s.