Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 5/2/2022
Publication Date: N/A
Technical Abstract: For centuries rootstocks were considered just a means to propagate delectable fruit. In the 20th century they were used to dwarf plants, increase per hectare productivity, enable high density production systems, resist some very important disease and insects and tolerate some abiotic stresses. As our understanding about root-shoot relationships increases, we are developing more opportunities to utilize the breeding efficiencies generated by separating root (rootstock) trait selection from scion trait selection to include traits that were not envisioned possible. Combined with the increased ability to dissect traits into their DNA components (and derived gene expression) we can imagine being able to use rootstocks to modulate more than the “traditional” traits. For example, we have recently discovered that apple rootstocks are able to modulate the scion’s gene expression, hormone flux, nutrient concentration and metabolite production and concentration. In the near future we may be able to leverage rootstocks to plant orchards that have increased fruit quality, have reduced fruit storage disorders, are more mechanization compatible, or that deliver therapeutic molecules to scions to resist more disease pressures. With increasing diversity in the development of new scion varieties it will become more important to precisely match rootstock and scion genotype to with the climate, soil and management system to optimize orchard productivity and efficiency hence the term “designer rootstock” is meant to describe a unique rootstock that is compatible with a specific scion, soil, climate and management parameters which enables higher efficiencies in the production of high-quality fruit and nuts. This evolution can be imagined and achieved for many of the tree crops that currently lack a designer rootstock component leading to enormous benefits from such systems. The development and application of rootstock systems with novel traits is poised to provide the world with more diverse, affordable, environmentally sustainable horticultural tree crops.