Dominated "Inheritance" of Endophytes in Grapevines from Stock Plants via In Vitro-Cultured Plantlets: The Dawn of Plant Endophytic Modifications

We hypothesize herein the "inheritance" of endophytes in grapevines through in vitro-culture plantlets (IVCPs) from a stock plant to established plants, and, subsequently, that endophytes can be modified at the IVCP stage to emphasize one or more of those "heritable" endophytes in later-developed plants. Using a DNA amplicon sequencing approach, we investigated the dynamic successions of endophytic communities in two taxonomically different varieties of grapevines from IVCPs (stage 1) to plants of later growth stages (stages 2-4). Despite the great alterations of endophytic amplicon sequence variants (ASVs) during the development of grapevines, our results demonstrated the dominant preservation of earlier-stage-acquired endophytic ASVs in grapevines of later stages. More importantly, we detected the dominant "inheritances" of the IVCP-borne ASVs, which succeeded from the stock grapevine throughout all growth stages of grapevines, with a few of these ASVs accounting for the major relative abundance (RA: 35-76%) in later-established grapevines. Notably, most of these dominantly "inherited" IVCP-borne endophytes belong to genera from which species have been frequently reported to have great agricultural and horticultural importance. In addition, horizontally transmitted endophytic (HTE) ASVs are able to dominate in later-developed grapevines. This work illustrates the evolution of endophytes from IVCPs to plants of later-growth stages. The results suggest a strategy to "breed" plant lines with certain beneficial endophytes at the IVCP stage, which has been termed herein as "plant endophytic modification".