![]() ![]() The genus Agrobacterium is used in genetic engineering. Spore-forming bacteria exist, but are only associated with storage rots, not with field diseases.Īntibiotics may be used to control many plant pathogenic bacteria. ![]() Bacterial shapes are: rod-shaped (bacilli), spherical (cocci), ellipsoidal, comma shaped, or filamentous/coiled (spirilli).Īll plant pathogenic bacteria are rod-shaped (with the exception of Streptomyces). About 80 species of bacteria cause plant diseases. Bacteria often have one or more flagella (i.e., they are mobile).Ībout 1600 bacterial species are known, most are strictly saprophytic. At this rate, a single bacterium would produce about 3 X 10 11 progeny in 24 hours (about 300 billion individuals). A typical bacterial cell is about 1 micrometer in diameter.īacteria can divide very rapidly: under proper conditions, some bacteria can divide every 20 minutes. They are much smaller than fungi, but can be seen with a light microscope. Bacteria have cell membranes and rigid cell walls. Plant pathogenic bacteria are heterotrophs (they require external source of organic carbon). Discussionįossil prokaryotes appear in rocks about 3.5 million years of age. naturalist Christian Gottfried Ehrenberg (1795-1876). Introduced as a scientific word 1838 by Ger. of baktron "stick, rod," from PIE *bak- "staff used for support." So called because the first ones observed were rod-shaped. ![]() Bacteria are unicellular, micrscopic organisms that lack chlorophyll and multiply (repoduce) by binary fission (simple cellular division).Įtymology. The ribosomes are not organized into a nucleus (i.e., the DNA is not bound my a membrane. A bacterium is a prokaryotic (containing small ribosomes (70S)) organism. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |