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recombination

(Encyclopedia)recombination, process of “shuffling” of genes by which new combinations can be generated. In recombination through sexual reproduction, the offspring's complete set of genes differs from that of ...

fungal infection

(Encyclopedia)fungal infection, infection caused by a fungus (see Fungi), some affecting animals, others plants. Serious damage is done to crops each year by fungal infections of plants such as smuts, rusts, ergo...

blight

(Encyclopedia)blight, general term for any sudden and severe plant disease or for the agent that causes it. The term is now applied chiefly to diseases caused by bacteria (e.g., bean blights and fire blight of frui...

gall, in botany

(Encyclopedia)gall, abnormal growth, or hypertrophy, of plant tissue produced by chemical or mechanical (e.g., the rubbing together of two branches) irritants or hormones. Chemical irritants are released by parasit...

Pasteur, Louis

(Encyclopedia)Pasteur, Louis păstŭrˈ, Fr. lwē pästörˈ [key], 1822–95, French chemist. He taught at Dijon, Strasbourg, and Lille, and in Paris at the École normale supérieure and the Sorbonne (1867–89)....

antitoxin

(Encyclopedia)antitoxin, any of a group of antibodies formed in the body as a response to the introduction of poisonous products, or toxins. By introducing small amounts of a specific toxin into the healthy body, i...

amphotericin B

(Encyclopedia)amphotericin B ămˌfətĕrˈĭsĭn [key], antibiotic that halts the growth of several disease-causing fungi. Discovered in 1956, it is produced by bacteria of the genus Streptomyces. It is used in lo...

actinomycin

(Encyclopedia)actinomycin ăkˌtənōmīˈsən [key], any one of a group of antibiotics produced by bacteria of the genus Streptomyces. Actinomycin was the first antibiotic reported to be able to halt cancer; howev...

Cohn, Ferdinand

(Encyclopedia)Cohn, Ferdinand fĕrˈdĕnänt kōn [key], 1828–98, German botanist. He is considered a founder of the science of bacteriology. From his early studies of microscopic life he developed theories of th...

leaven

(Encyclopedia)leaven lĕvˈən [key], agent used to raise bread or other flour foods. Physical leavens include water vapor, which is released as steam at high temperatures (as in popovers), and air, which is incorp...