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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...

decay of organic matter

(Encyclopedia)decay of organic matter or putrefaction, process whereby heterotrophic organisms, including some bacteria, fungi, saprophytic plants, and lower animals, utilize the remains of once-living tissue as a ...

elm

(Encyclopedia)elm, common name for the Ulmaceae, a family of trees and shrubs chiefly of the Northern Hemisphere. Elm trees (genus Ulmus) have a limited use as hardwoods for timber, especially the rock or cork elm ...

smut

(Encyclopedia)smut, name for an order of parasitic fungi (Ustilaginales) and the various diseases of plants caused by them. Smuts produce sootlike masses of spores on the host. The spore masses may break up into a ...

rose of Jericho

(Encyclopedia)rose of Jericho, common name for two plants belonging to different families in the plant kingdom. One, an annual desert plant (Anastatica hierochuntica) of the family Cruciferae (or Brassicaceae; must...

prion

(Encyclopedia)prion prēˈŏn [key], abnormal form of a protein found in mammals, now generally believed to cause a group of diseases known as prion diseases or transmissible spongiform encephalopathies, which are ...

plant breeding

(Encyclopedia)plant breeding, science of altering the genetic pattern of plants in order to increase their value. Increased crop yield is the primary aim of most plant-breeding programs; advantages of the hybrids a...

balm of Gilead

(Encyclopedia)balm of Gilead gĭlˈēəd [key], name for several plants belonging to different taxonomic families. The historic Old World balm of Gilead, or Mecca balsam, is a small evergreen tree (Commiphora gilea...

locoweed

(Encyclopedia)locoweed or crazyweed [Span. loco=crazy], any of several American species of the genera Astragalus and Oxytropus, north-temperate leguminous plants of the family Leguminosae (pulse family), that, when...

parasite

(Encyclopedia)parasite, plant or animal that at some stage of its existence obtains its nourishment from another living organism called the host. Parasites may or may not harm the host, but they never benefit it. T...