Integrating stay-green and PIN-FORMED genes: PIN-FORMED genes as potential targets for designing climate-resilient cereal ideotypes

Plant architecture modification (e.g. short-stature crops) is one of the key outcomes of modern crop breeding for high-yielding crop varieties. In cereals, delayed senescence, or stay-green, is an important trait that enables post-anthesis drought stress adaptation. Stay-green crops can prolong photosynthetic capacity during grain-filling period under post-anthesis drought stress, which is essential to ensure grain yield is not impacted under drought stress conditions. Although various stay-green quantitative trait loci have been identified in cereals, the underlying molecular mechanisms regulating stay-green remain elusive. Recent advances in various gene-editing technologies have provided avenues to fast-track crop improvement, such as the breeding of climate-resilient crops in the face of climate change. We present in this viewpoint the focus on using sorghum as the model cereal crop, to study PIN-FORMED (PIN) auxin efflux carriers as means to modulate plant architecture, and the potential to employ it as an adaptive strategy to address the environmental challenges posed by climate uncertainties. Stay-green is a valuable trait in crop breeding that enables plants to remain photosynthetically active longer and delay senescence during grain filling under post-anthesis drought stress. In sorghum, the expression of stay-green is a consequence of regulation of the water supply and demand framework through modulation of plant canopy and root architecture. Several studies have identified members of the PIN-FORMED (PIN) family of auxin efflux carriers as potential candidate genes that can modulate plant architecture to express stay-green sorghum. Using sorghum as the model species, further research on PIN auxin efflux carriers as a means to modulate plant architecture holds the potential to employ it as an adaptive strategy for crop breeding to address the environmental challenges pose by climate uncertainties.

Automated summary

Plant architecture modification through gene-editing technologies like PIN auxin efflux carriers can be used as an adaptive strategy in crop breeding to address climate uncertainties. Stay-green trait plays an important role in enabling plants to remain photosynthetically active and delay senescence during grain filling under post-anthesis drought stress. Sorghum serves as a model crop for researching the potential of using PIN auxin efflux carriers to modulate plant architecture for climate-resilient crops.