Diseases caused thousand species of bacteria found in nature. Many of them carry out the biochemical processes necessary for the continuation of life, such as bacterial or redutsenty detritivores, feeding on nonliving organic processing it through the ecosystem. There are, however, hundreds of species of bacteria that cause disease in humans, animals and plants. Bacteria prokaryotycheskyh microorganismsi. ie, unicellular organisms, in which nuclear matter is not concluded
in the membrane (see also). There are two main types of bacteria, >> << and they are different variations as part of their cell wall and cytoplasmic membrane and some metabolic functions. Plant pathogens belonging to eubacteria. Eubacteria can be divided into three groups:
Gram-negative bacteria,
Gram-positive bacteria, mycoplasmas and spiroplasmas, referred to as
mycoplasma organisms (MLOs). Gram-negative and gram-positive bacteria are allocated on the basis of their cell wall structure, which affects the ability of bacteria to respond >> << one of the most spots in bacteriological laboratories. A distinctive feature of the MLOs are no cell wall, and their external border instead cytoplasmic membrane, which gives unusual properties not found in most eubacteria. MLOs are taxonomic class Mollicutes. Plant diseases caused by MLOs are grouped as a reduction agent (characterized by loss of energy, reducing the yield of fruit, and eventually death) and agents virescence (greening flowers) and abnormalities. The main families of bacteria, plants are pathogenic Agrobacterium,
Clavibacter,
Erwinia, Pseudomonas
,
Xanthomonas, and
Xylella. Except
species Streptomyces, all of them small, isolated, bacillary cells is 0. 5 to 1. 0 micrometer (0. 00002 0. 00004 inches) in width and 1. From 0 to 3. 5 micrometers in length. Streptomycetes develop branched mycelium (narrow, filamentous growth) with curved chains of conidia (spores) on the ends of the mycelium. Streptomyces is a gram-positive, most species of other genera of Gram-negative. Bacterial diseases can be divided into four main categories depending on the degree of tissue damage plants and the symptoms they cause, which may include
vascular wilt, necrosis, soft rot, and tumors. Vascular wilt results of bacterial invasion of plants. The following reproduction and prevents blocking of the movement (displacement) of water and nutrients through ksilemy plant host. Hanging, wilting or death of aerial plant structures can occur, examples
, alfalfa, tobacco, tomatoes, pumpkin and (like zucchini, pumpkin, cucumber) and black rot cruciferous. Pathogens can result in
in secreting a toxin (poison). Symptoms include the formation of leaf strattera 10mg spot, stem plant disease, or ulcers. Soft rot disease caused by pathogenic microorganisms that produce enzymes that can decompose the structure of cell walls, thus destroying the structure of plants tissuei. E., Plant tissue is softened (soft and watery). Soft rot
usually occur on fleshy vegetables such as potatoes, carrots, eggplant, zucchini and tomatoes. diseases caused by bacteria that stimulate uncontrolled reproduction, resulting in abnormally large structures. Most bacteria produce a primary symptom, but some make the choice or combination of symptoms. In general, it is not particularly difficult to say whether the plant depends on bacterial pathogens, however, detection of the pathogen to species level to the selection and characterization of the pathogen, using multiple laboratory methods (
see. Above technological advances in the identification of pathogenic agents). To the bacteria produce disease of plants, bacteria must first penetrate the tissue and plant breeding. Bacterial pathogens enter plants through, mainly produced by bad weather, people, tools and equipment, insects and nematodes, or through natural openings such as stomates, chechevichkami, hydathodes, nectar glands, and. Most invaders leaves transferred from plant to plant by wind rain and dust. People spread the bacteria by cultivation, grafting, cutting and transporting sick plant material. Animals, including insects and mites, and other common means of transmission. Some bacteria, such as bacterial or parasite Stuart, wilting corn (
Erwinia stewartii), not only cover >> << but also survive the winter in this insect. Under adverse conditions for growth and reproduction, the bacteria remain dormant or inside plant tissue. Some, such as bacteria
, can survive for months or years in soil. Bacterial diseases are influenced by temperature and humidity. Often the difference just a few degrees of temperature determines >> << will be developed. In most cases, moisture, water film on the surface of plants is essential to establish infection. In general, the diseases caused by bacteria on hard to control. This is partly due to a speed of invasion, as bacteria enter natural openings or wounds directly. Direct input also allows them to avoid the toxic effects of chemical remedies. Loss of bacterial diseases is reduced through the use of pathogens
seeds grown in arid regions. Examples of diseases is controlled using this method include bacterial diseases of plants beans and peas, black rot and bacterial spot cruciferous cancer and tomato. Treatment of seeds in hot water at a temperature of about 50 ° C (120 F) is also effective for Cruciferous, pumpkin, carrots, eggplant, peppers and tomatoes. Bactericidal seed compounds
manage certain bacterial diseases such as angular leaf spot of cotton, gladiolus scab and rot of ornamentals. Rotation with nonhost crops reduces losses from wilting alfalfa plant diseases of beans and peas, black rot Cruciferous, gallic and bacterial spot of tomato and cancer. Elimination and exclusion of host plants was useful against cancer citrus, cotton angular leaf spot, and gallic. Resistant varieties of crops have been developed to reduce losses from the weakening of alfalfa, corn and tobacco; corner chlorosis cotton and tobacco, as well as bacterial pustule of soybeans and others. Protective insecticidal sprays to help fight against bacterial diseases such as weakening sweet corn and melons and soft rot iris. Protective bactericidal paints, or sweeping, containing copper or antibiotics used against bacterial spot beans, celery, bacterial burn, gallic, blackleg of delphinium and hazelnut and walnut plant diseases. Finally, health measuresi. ie, Clear to plow crop debris, destruction of volunteer plants and weeds, pruning and grafting sterilization toolsas and the abandonment of cultivation, when the leaves are wet, overhead watering and spraying house plants, and late cutting or grazing alfalfa and other crops, useful in reducing the incidence of bacterial diseases. Descriptions of several plant diseases caused by bacteria are listed in the table. Articles from Britannica encyclopedias for elementary and secondary schools. There are more than 80,000 plant diseases known worldwide. In fact, all plants are vulnerable to attack disease. Crops are often victims, and crop disease can lead to huge agricultural and economic losses. .
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