By lifting a gene from wild rice and breeding it into domestic crops, researchers have created a perennial crop that can live for two years or more. That could lead to rice that can produce several yields from one plant—reducing fertilizer use, locking carbon into the soil, and more.
Despite this, the researchers’ task isn’t complete: the longer-lasting rice plants don’t yet produce extra grain. But their survivability is considered a huge step towards that goal.
The new Science study set out to tackle a major trade-off of annual crops, which is that in the process of breeding to make them produce higher yields, they have lost the longevity of their wild ancestors, which can live for many seasons. Instead, annual grain crops typically die off after the first harvest, meaning they must be planted over and over again.
The researchers wanted to see if they could bring together the beneficial traits of each by experimentally crossing wild grasses with domesticated ones. They selected two in particular: the common domestic rice Oryza sativa, and a long-lived wild cousin called Oryza rufipogon that can produce several successive harvests. Crossing these two species produced hundreds of plants, and from these hybrid offspring the researchers selected one that both had the cultivated rice traits, but maintained the wild ability to keep producing new shoots, called ‘tillers’, after it had flowered and produced the first round of grain.
The secret behind this continued growth, the researchers discovered, was a segment of DNA containing two genes, called MIR156B and MIR156C. When they experimentally switched these genes off in a sample of wild rice plants, they lost the ability to produce new shoots after flowering, confirming their importance in the process.
But in their active form, these genes enabled the hybrid rice to keep producing new tillers. In fact, compared to annual rice crops, the hybrid rice went on to produce roughly 60 more tillers per plant after the flowering and seeding period, when annuals usually die off. The new growth also pushed the rice plants far beyond the normal range of annual rice, with the hybrid plants continuing to grow for the full two-year length of the study.
For now, this scientific breakthrough hasn’t quite managed to produce more grain, because the secondary tillers didn’t produce the necessary seeds to become rice. This remains a puzzle, and marks the next challenge.
Meanwhile, the case for creating more perennial crops is clear: more productive carbon-rich soils, huge reductions in fertilizer, and greater biodiversity, already shown with some grain crops like wheat. With this new genetic scaffolding in place, the researchers say they believe their findings will inspire ongoing plant breeding efforts, and accelerate the route to a perennial future.
Han et. al. “Resetting of a tandem microRNA156 enables vegetative perennial growth in rice.” Science. 2026.
Image: ©Anthropocene Magazine
