b'Multi-Stack Soybean Traits Look to an Ambitious FutureWhats in store as multi-stack traits continue to develop? Alex MartinIT WAS 2017when the first multi- to think about stacking multiple modes of stack trait soybeans entered theaction or multiple genes into a single trait commercial market. Now, five years later,conceptto bring out that performance the soybean trait market has changedand durability. theres been a shift away from single-stack soybean traits, and multi-stack traitsThe Ins and Outs of Trait Stack seem to be the preferred seed choice ofCompatibilitycustomers in the U.S. Figuring out how to make a perfect stack That means, multi-stack soybean traitswith multiple genes starts with a broad are about to become more and morefunnel, says Greene.ambitious as breeding efforts continue toThat gives us the ability to identify see what traits can be stacked to give younew modes of action or new sites of action more modes of action and prevent weed,that comes through our pipeline, and were pest and disease resistance in the field.testing it against current genes or traits in So much of the development of traitsthe marketplace as well, Greene says. As starts with the grower in mind, says Tomwe think about bringing those together, its Greene, senior research director andreally focused on that process of identify-global leader of biotechnology at Cortevaing how to best optimize expression of Agriscience. Understanding grower chal- each of those and how to build a molecular lenges is important to keep in mind thatcassette that expresses multiple genes in view of trying to support the grower whilethe right way. trying to maximize productivity. That means theres a lot of work to fine For Greene, multi-stack traits cametune gene expression for a single gene into perspectivewith the former legacyconfiguration. Each individual genes and companies, now Corteva, as the teamproteins that the gene codes for needs to looked to see how to combat challengesbe tested and brought together in a single like weeds and insects, along with thegene configuration. natural evolution of resistance develop- Bringing those together in a single ment, while giving farmers choices thatmolecular configuration drives a single meet their needs.molecular stack that can deliver a trait.As those resistance mechanisms beginOne of the biggest challenges with to develop, we realized that we neededhaving multiplies is really building the multiple modes of action to provide thatproduct within the breeding organization durability and that performance ourand the breeding process, Greene adds. growers needed to see, he says. As weWhen you start managing multiple loci in a evolved into those second-generationgenome, it adds tremendous complexity.trait technologies, thats when we beganSimplifying those locithe physical 24/ SEEDWORLD.COMDECEMBER 2022'