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Xanthomonas Campestris Pv. Campestris
Black rot, caused by the bacterium ''Xanthomonas campestris'' pv. ''campestris'' (Xcc), is considered the most important and most destructive disease of crucifers, infecting all cultivated varieties of brassicas worldwide.Alvarez AM. "Black rot of crucifers." In: Slusarenko AJ, Fraser RSS, van Loon LC (Eds.) ''Mechanisms of Resistance to Plant Diseases.'' Dordrecht, The Netherlands: Kluwer Academic Publishers, 2000. pp 21-52. This disease was first described by botanist and entomologist Harrison Garman in Lexington, Kentucky, US in 1889. Since then, it has been found in nearly every country in which vegetable brassicas are commercially cultivated. Host infection by Xcc can occur at any stage of the plant life cycle. Characteristic symptoms of black rot caused by Xcc are V-shaped chlorotic to necrotic lesions extending from the leaf margins and blackening of vascular tissues. The pathogen thrives in warm and humid climates and is rapidly disseminated in the field. Use of clean ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bacteria
Bacteria (; singular: bacterium) are ubiquitous, mostly free-living organisms often consisting of one biological cell. They constitute a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria were among the first life forms to appear on Earth, and are present in most of its habitats. Bacteria inhabit soil, water, acidic hot springs, radioactive waste, and the deep biosphere of Earth's crust. Bacteria are vital in many stages of the nutrient cycle by recycling nutrients such as the fixation of nitrogen from the atmosphere. The nutrient cycle includes the decomposition of dead bodies; bacteria are responsible for the putrefaction stage in this process. In the biological communities surrounding hydrothermal vents and cold seeps, extremophile bacteria provide the nutrients needed to sustain life by converting dissolved compounds, such as hydrogen sulphide and methane, to energy. Bacteria also live in symbiotic and parasitic relationsh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Exopolysaccharides
Extracellular polymeric substances (EPSs) are natural polymers of high molecular weight secreted by microorganisms into their environment. EPSs establish the functional and structural integrity of biofilms, and are considered the fundamental component that determines the physicochemical properties of a biofilm. EPS in the matrix of biofilms provides compositional support and protection of microbial communities from the harsh environments. Components of EPS can be of different classes of polysaccharides, lipids, nucleic acids, proteins, Lipopolysaccharides, and minerals. Components EPSs are mostly composed of polysaccharides (exopolysaccharides) and proteins, but include other macromolecules such as DNA, lipids and humic substances. EPSs are the construction material of bacterial settlements and either remain attached to the cell's outer surface, or are secreted into its growth medium. These compounds are important in biofilm formation and cells' attachment to surfaces. EPS ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xanthan
Xanthan gum () is a polysaccharide with many industrial uses, including as a common food additive. It is an effective thickening agent, emulsifier, and stabilizer that prevents ingredients from separating. It can be produced from simple sugars using a fermentation process and derives its name from the species of bacteria used, ''Xanthomonas campestris''. History Xanthan gum was discovered by Allene Rosalind Jeanes and her research team at the United States Department of Agriculture, and brought into commercial production by CP Kelco under the trade name Kelzan in the early 1960s. It was approved for use in foods in 1968 and is accepted as a safe food additive in the USA, Canada, European countries, and many other countries, with E number E415, and CAS number 11138-66-2. Xanthan gum derives its name from the species of bacteria used during the fermentation process, ''Xanthomonas campestris''. Uses Xanthan gum, 1%, can produce a significant increase in the viscosity of a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cultivars
A cultivar is a type of Horticulture, cultivated plant that people have selected for desired phenotypic trait, traits and when Plant propagation, propagated retain those traits. Methods used to propagate cultivars include: division, root and stem cuttings, offsets, grafting, micropropagation, tissue culture, or carefully controlled seed production. Most cultivars arise from purposeful human genetic engineering, manipulation, but some originate from wild plants that have distinctive characteristics. Cultivar names are chosen according to rules of the International Code of Nomenclature for Cultivated Plants (ICNCP), and not all cultivated plants qualify as cultivars. Horticulturists generally believe the word ''cultivar''''Cultivar'' () has two meanings, as explained in ''#Formal definition, Formal definition'': it is a classification category and a taxonomic unit within the category. When referring to a taxon, the word does not apply to an individual plant but to all plants that s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydathodes
A hydathode is a type of pore, commonly found in angiosperms, that secretes water through pores in the epidermis or leaf margin, typically at the tip of a marginal tooth or serration. Hydathodes occur in the leaves of submerged aquatic plants such as ''Ranunculus fluitans'' as well as herbaceous plants of drier habitats such as '' Campanula rotundifolia''. They are connected to the plant vascular system by a vascular bundle. Hydathodes are commonly seen in water lettuce, water hyacinth, rose, balsam, and many other species. Hydathodes are made of a group of living cells with numerous intercellular spaces filled with water, but few or no chloroplasts, and represent modified bundle-ends. These cells (called ''epithem cells'') open out into one or more sub-epidermal chambers. These, in turn, communicate with the exterior through an open water stoma or open pore. The water stoma structurally resembles an ordinary stoma, but is usually larger and has lost the power of movement. Hy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Epicotyl
An epicotyl is important for the beginning stages of a plant's life. It is the region of a seedling stem above the stalks of the seed leaves of an embryo plant. It grows rapidly, showing hypogeal germination, and extends the stem above the soil surface. A common misconception is that the epicotyl, being closer to the apex of the plant, is the first part to emerge after germination - rather, the hypocotyl, the region of the stem between the point of attachment of the cotyledons and the root - forms a hook during hypogeal germination and pushes out of the soil, allowing the more delicate tissues of the plumules and apical meristem to avoid damage from pushing through the soil. The epicotyl will expand and form the point of attachment of the shoot apex and leaf primordia or "first true leaves". Cotyledons may remain belowground or be pushed up aboveground with the growing stem depending on the plant species in question. In plant physiology, the epicotyl is the embryonic shoot above the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Black Rot Lifecycle
Black is a color which results from the absence or complete Absorption (electromagnetic radiation), absorption of visible spectrum, visible light. It is an achromatic color, without hue, like white and grey. It is often used symbolically or figurative language, figuratively to represent darkness. Black and white have often been used to describe opposites such as good and evil, the Dark Ages (historiography), Dark Ages versus Age of Enlightenment, and night versus day. Since the Middle Ages, black has been the symbolic color of solemnity and authority, and for this reason it is still commonly worn by judges and magistrates. Black was one of the first colors used by artists in Neolithic cave paintings. It was used in ancient Egypt and Greece as the color of the underworld. In the Roman Empire, it became the color of mourning, and over the centuries it was frequently associated with death, evil, Witchcraft, witches, and Magic (supernatural), magic. In the 14th century, it was worn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Black Rot Of Cabbage Symptoms
Black is a color which results from the absence or complete absorption of visible light. It is an achromatic color, without hue, like white and grey. It is often used symbolically or figuratively to represent darkness. Black and white have often been used to describe opposites such as good and evil, the Dark Ages versus Age of Enlightenment, and night versus day. Since the Middle Ages, black has been the symbolic color of solemnity and authority, and for this reason it is still commonly worn by judges and magistrates. Black was one of the first colors used by artists in Neolithic cave paintings. It was used in ancient Egypt and Greece as the color of the underworld. In the Roman Empire, it became the color of mourning, and over the centuries it was frequently associated with death, evil, witches, and magic. In the 14th century, it was worn by royalty, clergy, judges, and government officials in much of Europe. It became the color worn by English romantic poets, businessmen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stomata
In botany, a stoma (from Greek ''στόμα'', "mouth", plural "stomata"), also called a stomate (plural "stomates"), is a pore found in the epidermis of leaves, stems, and other organs, that controls the rate of gas exchange. The pore is bordered by a pair of specialized parenchyma cells known as guard cells that are responsible for regulating the size of the stomatal opening. The term is usually used collectively to refer to the entire stomatal complex, consisting of the paired guard cells and the pore itself, which is referred to as the stomatal aperture. Air, containing oxygen, which is used in respiration, and carbon dioxide, which is used in photosynthesis, passes through stomata by gaseous diffusion. Water vapour diffuses through the stomata into the atmosphere in a process called transpiration. Stomata are present in the sporophyte generation of all land plant groups except liverworts. In vascular plants the number, size and distribution of stomata varies widely. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pseudomonas Marginalis
''Pseudomonas marginalis'' is a soil bacterium that can cause soft rots of plant tissues. It infects List of poinsettia diseases, poinsettia, List of lettuce diseases, lettuce, and List of crucifer diseases, crucifers (List of canola diseases, canola, List of mustard diseases, mustard). Based on 16S rRNA analysis, ''P. marginalis'' has been placed in the ''Pseudomonas fluorescens, P. fluorescens'' group. References External links Type strain of ''Pseudomonas marginalis'' at Bac''Dive'' - the Bacterial Diversity Metadatabase Pseudomonadales Bacterial plant pathogens and diseases Ornamental plant pathogens and diseases Food plant pathogens and diseases Lettuce diseases Bacteria described in 1918 {{Pseudomonadales-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Erwinia
''Erwinia'' is a genus of Enterobacterales bacteria containing mostly plant pathogenic species which was named for the famous plant pathologist, Erwin Frink Smith. It contains Gram-negative bacteria related to ''Escherichia coli'', ''Shigella'', ''Salmonella'', and ''Yersinia''. They are primarily rod-shaped bacteria. Many infect woody plants. A well-known member of this genus is the species '' E. amylovora'', which causes fire blight on apples, pears, and other Rosaceae crops; ''E. tracheiphila'', though, causes bacterial wilt of cucurbits. Other familiar species, such as '' E. carotovora'' (another major cause of plant diseases), are more distantly related to the fire blight bacterium, and have been moved to genera ''Brenneria'', ''Dickeya'', and '' Pectobacterium''. ''Erwinia aphidocola'' and ''E. persicina'' species were both observed to be present within the floral nectar microbial community of seven different orchid (''Epipactis'') flower species. ''E. aphidicola'' appear ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pectobacterium Carotovorum
''Pectobacterium carotovorum'' is a bacterium of the family Pectobacteriaceae; it used to be a member of the genus ''Erwinia''. The species is a plant pathogen with a diverse host range, including many agriculturally and scientifically important plant species. It produces pectolytic enzymes that hydrolyze pectin between individual plant cells. This causes the cells to separate, a disease plant pathologists term bacterial soft rot. Specifically, it causes beet vascular necrosis and blackleg of potato and other vegetables (hence the name ''carotovora'' – "carrot-eater"), as well as slime flux on many different tree species. Currently, there are four described subspecies of ''P. carotovorum'' (''carotovorum, brasiliense, odoriferum'', and ''actinidiae''). This bacterium is a ubiquitous plant pathogen with a wide host range (carrot, potato, tomato, leafy greens, squash and other cucurbits, onion, green peppers, African violets, etc.), able to cause disease in almost any plant ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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