固定種とは? Whats open pollinated seeds?

野菜の種には「固定種(open pollinated seeds)」と「F1品種(Filial 1 hybrid seeds)」があります。

  • 固定種:ある程度、成長速度や形などばらつきがあるが、次世代も形質の変わらない作物が育ちます。
  • F1種:1代目は成長速度・形が揃いますが、次世代は形質がばらけてしまいます。品種、作物によっては、 種子自体が実らないものがあります。




例えば、掛け合わせる品種の優性形質が「A 病気に強い」×「B 甘くて美味しい」などの場合、1代目の雑種はその特徴を揃って受け継いで生まれてきます。さらに、野菜の見た目も揃います。





  1. 種を考える by 無印良品
  2. タネが危ない by ネクストウィズダムファウンデーション
  3. 種採農家 岩崎政利さん by コレゾ、ホンモノ




What are open pollinated seeds?

There are two kinds of seeds in vegetables.
One is “open pollinated seeds”, the other is “Filial 1 hybrid seeds”.

open pollinated seeds : These seeds’s growing speed and shapes are not stable to some extent, but these seeds are able to grow to the next generation without characteristic quality change.

Filial 1 hybrid seeds : The growing speed and the shapes are stable in the first generation, but in the second generation these seeds lose their characteristic quality. Moreover, Depending on the breeds and the crops, there are the seeds which can not generate the seeds itself.

Naturally, all seeds were open pollinated seeds. This breed has been taking care by the farmers because they have sowed these seeds to grow up their vegetable and picked up the better seeds when they are harvesting. They have been doing this work from generation to generation to create better vegetables.
The vegetables have been left their seeds with diversity by nature so that the seeds are able to survive the change of evolution. What we are trying to say is “open pollinated seeds” have a character that are able to adjust themselves to changes climates and soil conditions while having their own qualities. If farmers sow the seeds of thick Japanese reddish“Miura-daikon”, some of them grow thick others grow thin. However, farmers have been keeping the seeds by picking up the seeds of thick reddish.

The vegetables had been grown in this way was consumed in various places.
However, as the times were changing to the times of high economic growth, quantity of the vegetables which are supplied have been largely increased.
After that, the times have come that vegetables are brought by trucks to throughout Japan, but “open pollinated seeds” was inefficient in the times of mass-production and mass-consumption.

In a while, “Filial 1 hybrid seeds” had appeared. This breed is what is called a hybrid vigor. This breed has a character that if the two breeds which are having different allele cross each other, the first generations will appear with equally having their parent’s dominant character.
For instance, if the breeds which are crossing have dominant character not “sweet and tasty” but “robust to disease”, the first generation will be born with taking over the same dominant character. Moreover, appearance of vegetables is completed as same.

As a matter of fact, this “Filial 1 hybrid seeds” are registered by the company which developed them. It is a kind of the copyright so if famers take the seeds freely, they will be banned by law. There are some concerns about situation that specific company has occupied the seeds. In fact, the prices of seed are rising year by year.

When the particular diseases are spread to the crops by extreme weather, the crops can survive if they have variety characters. Otherwise, there is a possibility that the crops (such as “Filial 1 hybrid seeds”) have same characters will disappear all at once.

In terms of these facts, it seems that people are increasing who really want to grow “open pollinated seeds” in their fields.