hinshu.jp The family trees of Japanese crop varieties
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The family trees of Japanese crop varieties

Most people know the name of a rice variety. Almost nobody knows its parents.

The crosses and the pedigrees are already public. They sit in NARO's rice variety database and in the Ministry of Agriculture's plant variety registration database. But what is listed there are line numbers — "Etsunan 17", "Ou 224" — and working out which of them came from the same cross means matching numbers by hand. The record exists; it is not in a readable form.

This site translates it into a family tree.

What is different here: every line has a source

Other pedigree charts exist. What is different here is that each parent-child link has been checked against a primary source, and carries a link to it. The sources are NARO's breeding reports and parent-variety listings, the Ministry's variety registration database, and the breeding reports of the prefectural agricultural experiment stations. An encyclopedia entry or a popular article, however widely repeated, is not treated as grounds for drawing a line.

A parent is recorded as mother or father only where the source says so in words. Where a cross is written only as "A/B", convention makes A the mother — but the source does not say it, so this site does not assert it. The distinction exists to leave unwritten things unwritten.

Where two sources disagree, neither is chosen as the truth. The disagreement is recorded as a disagreement, and the page states which reading was used and why.

How to use it

There are three ways in.

Down from Koshihikari. The list of its children shows what came out of it. Most of the varieties grown in quantity today sit on this branch.

Back to the ancestors. From Koshihikari's parents and grandparents back to the pre-war landraces, where the record of a cross stops.

Across. Pages that compare varieties sharing a single parent, lines that separated from one and the same cross, and the way the breeding reports themselves are written. What cannot be seen from one variety alone is collected here.

The data is also published as JSON. If you find an error, please report it. A correction is not a failure; it is evidence that the site is working.

The site currently holds 271 varieties, 323 parent-child links and 197 sources. Of those, 136 varieties have a page of their own, and 6 cases are recorded as sources disagreeing with each other. These figures are read straight from the data, so this line changes as the data grows.

Varieties covered