To do this, breeders use genetic markers to bring desirable traits from wild species into their cultivated cousins. Transferring those markers across species has been difficult at best, but a team of grapevine breeders, geneticists and bioinformatic specialists at Cornell AgriTech in Geneva, New York, has come up with a powerful new method.
Their research is detailed in “Haplotyping the Vitis Collinear Core Genome With rhAmpSeq Improves Marker Transferability in a Diverse Genus,” published Jan. 21 in Nature Communications.
The team’s new technique for developing genetic markers improves markers’ transfer rate across grapevine species by leaps and bounds – from 2% to 92%. With it, breeders worldwide can screen their collections and find out immediately which vines have the traits they want – regardless of what varieties they are, where they came from or which species their parents were.
“This new marker development strategy goes well beyond grapes,” said co-author Bruce Reisch, professor of horticulture in the College of Agriculture and Life Sciences, and leader of Cornell’s Grapevine Breeding and Genetics Program. “It’s applicable for breeding and genetic studies across different grape breeding programs, plant species and other diverse organisms.”
Breeders bring desired traits from native species into cultivated ones by identifying the DNA markers that point to trait-associated genes, selecting plants that carry them and breeding across species. For grapevines and other plants, though, evolution has reshuffled the genetic deck so fully that markers developed using certain grapevine species don’t work with wild species or their hybrids.
Yet it’s essential that breeders have reliable markers for creating new grape varieties with improved flavor, weather- or disease-resistance – especially as climate change increases disease pressure and alters the growing range for many cultivated varieties.
To create the genetic markers, the research team used new automated DNA sequencing technology to create a “core genome” for grapevines, matching important regions shared between 10 species’ genomes. Using powerful new rhAmpSeq genetic mapping technology, they targeted those regions to develop robust DNA markers.