How plants adapt to phosphorus shortages

How plants adapt to phosphorus shortages
Nov 13, 2025
By Farms.com

New discovery shows how crops adjust flowering when nutrients are low

Phosphorus is one of the most important nutrients for global food production, yet it comes from limited and non-renewable sources. As soils lose phosphorus and fertilizer supplies decline, researchers are searching for ways to help crops grow well using fewer inputs.  

A recent scientific breakthrough has revealed how plants naturally adapt to phosphorus shortages, providing new hope for nutrient-efficient crop breeding. 

Researchers at Michigan State University have discovered a signaling pathway that explains how plants delay flowering when phosphorus levels drop. In nature, plants slow their development during nutrient scarcity to conserve energy, but until now, the exact mechanism behind this process was unknown. 

“This is the first time we have seen such a direct link between nutrient status, protein movement inside the cell and control of flowering time,” said Associate Professor Hatem Rouached, senior author and faculty member in MSU’s Department of Plant, Soil and Microbial Sciences.  

“This discovery helps explain how plants translate nutrient stress into developmental timing. By understanding that mechanism, we can begin designing crops that flower and yield optimally even in nutrient-poor environments.” 

The study focused on Arabidopsis, a small flowering plant often used in research. Scientists observed that plants grown in low-phosphorus conditions flowered later than usual. Through genome-wide association mapping, they identified a key protein called bGLU25. Although this protein belongs to a family of enzymes, it does not break down carbohydrates. Instead, it acts as a messenger that reports nutrient status inside the plant. 

Under normal phosphorus levels, bGLU25 remains inside the endoplasmic reticulum. During phosphorus shortage, it is cut by another protein, SCPL50, causing it to move into the cytosol. This movement acts as a molecular switch that changes how the plant decides when to flower. 

Once released, bGLU25 binds to another protein, AtJAC1, which then traps a third protein, GRP7. GRP7 normally controls genes that influence flowering, so by preventing it from entering the nucleus, the plant increases Flowering Locus C activity and delays flowering. 

This finely tuned system helps plants survive until conditions improve. Scientists believe similar mechanisms also operate in crops like rice, offering new opportunities to breed varieties that flower reliably even in poor soils. 

Understanding this nutrient-responsive switch may guide the development of “nutrient-smart” crops that use less fertilizer, support environmental goals, and maintain stable yields in difficult conditions. 

Photo Credit: istock-pkujiahe