Why sourcing is the whole point

People use information like this to decide what seed or seedlings to buy. Somebody will buy a variety because they read here that it resists a disease. If we are wrong, the harm is real.

If a site claims to serve the public good, accuracy is the only thing holding that claim up.

The rules we hold to

Every single parent-child link carries a source — NARO, the MAFF plant variety registration database, or a prefectural agricultural experiment station.
Source URLs live in the data and are reachable from the page.
"Wikipedia said so" never passes, not once.
Where primary sources contradict each other, we record both and mark it as disputed. We do not draw a disputed link as settled fact.
Each page lists only the sources it actually used. We do not pad the list.

Sources are attached per parent-child relationship, not per variety.

How disputes are handled

The seed and pollen parents of Koshihikari, for instance, are stated in opposite order by NARO and by Niigata Prefecture, which bred it. The year of the cross is given as both 1944 and 1945.

We do not declare either side wrong. Both are presented with their sources, and we state which one the diagram follows.

On variety names

Variety names are proper nouns. In English we write Koshihikari — the romanised name. We do not translate it.

In the traditional Chinese edition we use a Chinese name only for varieties where a published source for that name can be cited. Otherwise the Japanese name stands. We do not invent translations.

Open data

The variety data on this site is published with its sources, in a reusable form.

Varieties: /data/rice/varieties.json
Relationships: /data/rice/relations.json
Sources: /data/rice/sources.json
Disputes: /data/rice/disputes.json

Licence: CC BY 4.0

The data above is published under Creative Commons Attribution 4.0 International (CC BY 4.0). Attribute the source and you may use it freely, commercially included, and adapt or redistribute it.

Suggested attribution:

hinshu.jp (IDEA Technology) https://hinshu.jp/ — CC BY 4.0

What the licence covers is the dataset we compiled — its structure and our descriptions. The underlying facts, such as a crossing combination or a year of breeding, are not copyrightable, and the NARO, MAFF and prefectural documents we link to carry their own terms. If you quote a primary source directly, follow that source's conditions.

When this site should stop

If the sourcing can no longer be maintained — that is, if accuracy drops — this site closes. That is its only withdrawal condition.

Our sourcing policy