By Blake Jackson
A new international study led in part by the University of Kentucky Martin-Gatton College of Agriculture, Food and Environment has pinpointed a key genetic shift that strengthens corn seeds during storage. The discovery offers plant breeders a focused genetic target for creating corn varieties that retain vigor longer and reduce seed loss.
Published in The Plant Cell, the research centers on a protein-repair enzyme called ZmPIMT1. Scientists found that natural differences in the gene’s regulatory region the segment of DNA that determines how much RNA and protein the plant produces play a major role in how well corn seeds withstand aging.
According to the study, certain corn lines possess a regulatory version that boosts ZmPIMT1 activity, giving seeds a stronger defense against the stresses associated with long-term storage.
For Bruce Downie, professor in the Department of Horticulture at Martin-Gatton CAFE and a core member of UK’s seed biology team, the findings highlight the essential role seeds play in human life.
“Roughly 70% of the human diet comes directly from seeds, and much of the rest depends on animals fed on seeds,” Downie said. “We eat them, wear them as cotton, ferment them into beverages and fuel. If seed lots fail, the costs hit farmers, companies and consumers all the way down the line.”
Working with professor Tianyong Zhao and professor Yumin Zhang of Northwest A&F University in China, the team identified two major versions of the ZmPIMT1 regulatory region across diverse corn lines.
One promotes higher levels of ZmPIMT1 mRNA, while the other includes a large insertion that suppresses expression and reduces the seed’s resilience to aging. Seeds with elevated ZmPIMT1 maintained higher germination rates and produced more vigorous seedlings during accelerated aging tests.
ZmPIMT1 protects essential proteins inside dry seeds, repairing damaged components rather than requiring the plant to rebuild them entirely. It plays a crucial role in supporting PABP2, a protein that helps determine which stored messages are translated during early germination.
Downie summarized the concept succinctly: “This reinforces what seed biologists call ‘Job’s rule.’ If you want a seed to survive dry storage, you must protect and repair the machinery of protein synthesis.”
By highlighting a clear genetic marker, the study provides breeders and seed companies with a practical tool for improving seed longevity and strengthening the reliability of commercial seed lots.
Photo Credit: gettyimages-awakr10
Categories: Kentucky, Crops, Corn, Education