A research team at Nagoya University in Japan has identified a previously unknown plant tissue that plays a crucial role in forming seeds. This marks the first time in 160 years that scientists have documented a newly recognized plant tissue. The finding opens the door to an entirely new research area and has already shown real-world potential, as the group has used the discovery to boost yields in major crops such as rice. The study appears in the journal Current Biology.

Scientists have known since 2005 that fertilization must occur for the developing seed body, called the hypocotyl, to draw nutrients from the ‘mother’ tissues of the plant. Gaining insight into how plants recognize when fertilization has succeeded is considered important for improving crop productivity during breeding efforts.

A Chance Observation Leads to a Breakthrough
The team, directed by Ryushiro Kasahara and Michitaka Nodaguchi, encountered the new tissue unexpectedly. Kasahara had been staining seeds to observe the buildup of callose, a waxy substance often examined for its role in fertilization, as part of an effort to confirm earlier research.

During this work, he came across something surprising.

“Plants fertilize by the insertion of a pollen tube, so most scientists are only interested in the place where this occurs. However, we found signals on the opposite side too,” he said. “Nobody was looking where I was looking. I remember being surprised, especially when we realized that this signal was particularly strong when fertilization failed.”

Further analysis revealed a distinctive rabbit-shaped tissue structure that functions as a gateway. This structure, named the ‘Kasahara Gateway’ in honor of its discoverer, represents the first new plant tissue identified since the mid-19th century.