Kathleen Drew-Baker - the saviour of のり, and therefore 寿司 and おにぎり.

The Wikipedia article on Kathleen Drew-Baker in Japanese.

Everyone loves sushi. Well not my mum, but almost everyone else. Today I learned (from www.arstechnica.com) that nori was saved by an Englishwoman who got fired as a lecturer at a university in England for the heinous crime of getting married. No married woman lecturers they said. Read the story. It's very interesting. For those who want a breakdown, read on.

Nori was once called 'lucky grass', as the harvest depended entirely on luck.

Then the luck ran out full stop, the nori plants stubbornly refusing to develop past the initial stages of cultivation.

Enter pollution, industrialisation, and a string of bad typhoons and nori was no more. By 1951 it was all over. 

But wait, enter Kathleen Drew-Baker. She was studying a type of seaweed called laver (I've heard of it, but only vaguely), that the Welsh would grind up and eat, and still do.

She resided in a seaside lab, studying the laver during the winter when it grew, but also noticed in the summer a different species. 

The winter stuff is leafy green seaweed (nori), while the summer pink sludgy stuff is a different species called Conchocelis. They work together, as below

• In the summer the nori sends out spores that collect and grow as pink sludge (conchocelis) in shells on the sea floor. 
• In the winter, the conchocelis send out spores that collect and grow as seaweed (nori) on debris (and bamboo poles)

That's right. One needs the other. The chicken or the egg story all over again. But if there isn't one, there isn't the other.

Anyhow, she got published in 1949 and got noticed by one Segawa Sokichi, who worked at the Shimoda Marine Biological Station. He had a read of what she had written and thought (rightly as it turned out) that if it was true for Welsh seaweed, it may be true for Japanese seaweed.

Everyone was looking for nori seeds, but there are no such things. Nori comes from the conchocelis, which had been wiped out by destruction of the shellbeds in which it lived

They got the shellbeds back in place, and people were happy munching on sushi and onigiri soon after.

The story continues with a very, very interesting and detailed breakdown of how nori is grown.

Information from arstechica.com, Picture from Wikipedia.