or bakanae disease(馬鹿苗病, バカナエビョウ, Bakanae-byo), from the Japanese for "foolish seedling", is a disease that infects the rice

Rice

Rice is the seed of the monocot plants Oryza sativa or Oryza glaberrima . As a cereal grain, it is the most important staple food for a large part of the world's human population, especially in East Asia, Southeast Asia, South Asia, the Middle East, and the West Indies...

 plant. It is caused by the fungus

Fungus

A fungus is a member of a large group of eukaryotic organisms that includes microorganisms such as yeasts and molds , as well as the more familiar mushrooms. These organisms are classified as a kingdom, Fungi, which is separate from plants, animals, and bacteria...

 Gibberella fujikuroi

Gibberella fujikuroi

Gibberella fujikuroi is a fungal plant pathogen. It causes bakanae disease in rice seedlings, by overloading them with the phytohormone gibberellin as its own metabolic byproduct.- External links :* * *...

, whose metabolism produces a surplus of gibberellic acid

Gibberellic acid

Gibberellic acid Gibberellic acid Gibberellic acid (also called Gibberellin A3, GA, and (GA3) is a hormone found in plants. Its chemical formula is C19H22O6. When purified, it is a white-to-pale-yellow solid....

. In the plant, this acts as a growth hormone

Growth hormone

Growth hormone is a peptide hormone that stimulates growth, cell reproduction and regeneration in humans and other animals. Growth hormone is a 191-amino acid, single-chain polypeptide that is synthesized, stored, and secreted by the somatotroph cells within the lateral wings of the anterior...

, causing hypertrophy

Hypertrophy

Hypertrophy is the increase in the volume of an organ or tissue due to the enlargement of its component cells. It should be distinguished from hyperplasia, in which the cells remain approximately the same size but increase in number...

. The afflicted plants, which are visibly etiolated

Etiolation

Etiolation is a process in flowering plants grown in partial or complete absence of light. It is characterized by long, weak stems; smaller, sparser leaves due to longer internodes; and a pale yellow color . It increases the likelihood that a plant will reach a light source, often from under the...

 and chlorotic, are at best infertile with empty panicle

Panicle

A panicle is a compound raceme, a loose, much-branched indeterminate inflorescence with pedicellate flowers attached along the secondary branches; in other words, a branched cluster of flowers in which the branches are racemes....

s, producing no edible grains; at worst, they are incapable of supporting their own weight, topple over, and die (hence "foolish seedling disease").

The earliest known report of bakanae is from 1828; it was first described scientifically in 1898 by Japanese

Japanese people

The are an ethnic group originating in the Japanese archipelago and are the predominant ethnic group of Japan. Worldwide, approximately 130 million people are of Japanese descent; of these, approximately 127 million are residents of Japan. People of Japanese ancestry who live in other countries...

 researcher Shotaro Hori, who showed that the causative agent was fungal.

Bakanae affects rice crops in Asia, Africa, and North America. In 2003, the International Rice Research Institute

International Rice Research Institute

The International Rice Research Institute is an international NGO. Its headquarters are in Los Baños, Laguna, Philippines, and it has offices in sixteen countries...

estimated bakanae-related crop losses at between 20% and 50% in Japan alone.