New Insight into the Composition of Wheat Seed Microbiota

Abstract

Endophytes are associated with host plants throughout their life history from seed germination to fruit development. One of the most important plant organs colonized by endophytic microbiota is the seed. The aim of this study was to determine the structure of the seed core microbiome inhabiting the endosperms and embryos of eight wheat cultivars with the use of a culture-independent technique. The seeds of Triticum aestivum L. cv. Hondia, Wilejka, STH, Opcja, Tybalt, Euforia and Triticum spelta L. cv. Rokosz and Schwabencorn (producer: Plant Breeding Strzelce Sp. z o.o. Group IHAR) were studied. Rokosz and Hondia were cultured in vitro and in vivo to identify obligatory bacterial endophytes. A restrictive analysis of reads originating from the in vitro plants has demonstrated that the bacterial genera Paenibacillus and Propionibacterium inhabiting Rokosz and Hondia plants have a status of obligatory microorganisms. Greater biodiversity of seed-borne endophytes was found in the seed endosperms than in the embryos. The multiple comparison analysis of the OTU abundance indicated that the seed part significantly influenced the relative abundance. The seed-born microbiome is not statistically significantly dependent on the wheat cultivars; however, it cannot be claimed that every wheat seed is the same.

Diversity and Structure of the Endophytic Bacterial Communities Associated With Three Terrestrial Orchid Species as Revealed by 16S rRNA Gene Metabarcoding

“…Among the most representative genera, Cutibacterium has been identified, which is widely known as a commensal and is part of the human skin microbiota. However, a recent study, in support of our data, demonstrated the presence of Cutibacterium as an endophyte of roots and leaves in the wheat cultivars Triticum spelta cv Rokosz and Triticum aestivum cv Hondia ( Kuźniar et al, 2020 ). It is also very interesting, as reported by Shaffer et al (2018) , that this genus has been classified as a hyphal endosymbiont of a leaf fungal endophyte ( Fusarium concolor ) from Hybanthus prunifolius .…”

Domestication affects the composition, diversity, and co-occurrence of the cereal seed microbiota

“…However, recent studies endorse more the idea of an interkingdom exchange of microbes during plant domestication than the possibility of contamination. For example, Kuźniar and colleagues [73] studied eight wheat seeds microbiota in different compartments of seed (the embryo, endosperm, and the seed coat) and they found Cutibacterium in all the parts of the studied cultivars. Many other recent studies also found Propionibacterium as a member of the core microbiota of cereal seeds such as wheat, barley, maize and rice [20] , [73] , [74] , [75] .…”

“…For example, Kuźniar and colleagues [73] studied eight wheat seeds microbiota in different compartments of seed (the embryo, endosperm, and the seed coat) and they found Cutibacterium in all the parts of the studied cultivars. Many other recent studies also found Propionibacterium as a member of the core microbiota of cereal seeds such as wheat, barley, maize and rice [20] , [73] , [74] , [75] . Interestingly, Campisano and colleagues [76] found a subspecies of Propionibacterium acnes in grapevine ( Vitis vinifera L.), which evolved from the human-associated strain since a time comparable with the beginning of grapevine domestication.…”

Bacterial Endophytes of Spring Wheat Grains and the Potential to Acquire Fe, Cu, and Zn under Their Low Soil Bioavailability

“…Our study confirmed that the microbiome of wheat grains depends on the wheat variety; the same trend was reported by Safin et al [ 66 ] and Comby et al [ 67 ]. Furthermore, Kuzniar et al [ 68 ] found that the seed-borne microbiome was not statistically significantly dependent on the wheat cultivars. Importantly, the seed-associated microbiotas, which are expected to be transferred vertically, have the potential to coadapt with their host over generations to different harsh environments [ 69 ].…”

“…Data regarding endophytes inhabiting spring wheat grains are equally scarce. It is worth emphasizing that grain endophytes are highly interesting due to their ability to be transmitted vertically between generations [ 62 , 63 , 64 , 65 , 66 , 67 , 68 , 69 , 70 ]. A better understanding and manipulation of endophytes are considered novel promising strategies to mitigate the adverse impacts of global climate change on agricultural production and to improve the nutritional quality of plant-based foods.…”