The sex of many animal species offspring is determined by their parents, but a recent report in the journal Science reveals that the sex of the offspring of a Japanese climbing fern plant is determined by the fern plant community.
Ferns determine their own sex for faster reproduction
The study shows that older ferns in the community secrete hormones that determine the sex of their offspring, maintaining a balanced sex ratio and enabling faster reproduction.
Ferns reproduce through gametophytes
Fern plants reproduce through spores, not seeds, and this study focused on the closest examination of the sexes of fern plants. Spores mature into adult plants, becoming gametophytes, which are either male, female, or hermaphroditic. If there are no other gametophytes surrounding a hermaphroditic gametophyte, it will maintain its hermaphroditic status and undergo self-fertilization, risking inbreeding for reproduction.
Sex of young Japanese fern plants influenced by older ferns
A group of molecular biologists at Nagoya University in Japan discovered that older gametophytes of Japanese fern plants can influence the sex of younger gametophytes nearby. This influence occurs in two steps. First, a signaling hormone called gibberellin promotes the development of male reproductive organs in gametophytes. Second, mature female gametophytes can produce gibberellin, but the gibberellin is "processed" by the female gametophyte by adding a methyl ester group to the gibberellin precursor molecule. This mechanism helps younger gametophytes acquire gibberellin and complete gibberellin production, resulting in the development of male reproductive tissues.
This mechanism allows older gametophytes to be female while increasing the number of male gametophytes, maintaining a balanced sex ratio and avoiding self-fertilization to preserve genetic diversity.
Gibberellin plays an important role in sex determination and growth
In the post-World War II Green Revolution, agricultural production and plant breeding technologies led to a significant increase in wheat and rice yields worldwide, with gibberellin playing a crucial role. Gibberellin is a growth hormone for these crops, enhancing adaptability, shortening growth cycles, and making them more resilient to weather changes.
Gibberellin played a significant role in the post-World War II Green Revolution, enabling agricultural production and plant breeding technologies to increase wheat and rice yields worldwide.
