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Cercospora Arachidicola
''Cercospora arachidicola'' is a fungal ascomycete plant pathogen that causes early leaf spot of peanut. Peanuts (''Arachis hypogaea'') originated in South America and are cultivated globally in warm, temperate and tropical regions. All cultivars of peanuts are equally susceptible to peanut fungal pathogens; however, ''C. arachidicola'' is an economically important peanut pathogen and is responsible for significant economic losses in the peanut industry, more specifically in the Southeastern, Eastern, and the Southwestern United States. Early leaf spot of peanut can drastically reduce yields, leading to economic downturn of the peanut crop economy. Annual crop losses in the United States range anywhere from less than 1% to greater than 50% depending on disease management and treatment. Host and symptoms ''Cercospora arachidicola'' only infects peanut plants, causing symptoms of brown lesions with chlorotic rings on the stems, leaves, and petioles. The first macroscopic symptom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ascomycota
Ascomycota is a phylum of the kingdom Fungi that, together with the Basidiomycota, forms the subkingdom Dikarya. Its members are commonly known as the sac fungi or ascomycetes. It is the largest phylum of Fungi, with over 64,000 species. The defining feature of this fungal group is the " ascus" (), a microscopic sexual structure in which nonmotile spores, called ascospores, are formed. However, some species of the Ascomycota are asexual, meaning that they do not have a sexual cycle and thus do not form asci or ascospores. Familiar examples of sac fungi include morels, truffles, brewers' and bakers' yeast, dead man's fingers, and cup fungi. The fungal symbionts in the majority of lichens (loosely termed "ascolichens") such as ''Cladonia'' belong to the Ascomycota. Ascomycota is a monophyletic group (it contains all descendants of one common ancestor). Previously placed in the Deuteromycota along with asexual species from other fungal taxa, asexual (or anamorphic) ascomyce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Propagule
In biology, a propagule is any material that functions in propagating an organism to the next stage in its life cycle, such as by dispersal. The propagule is usually distinct in form from the parent organism. Propagules are produced by organisms such as plants (in the form of seeds or spores), fungi (in the form of spores), and bacteria (for example endospores or microbial cysts). In disease biology, pathogens are said to generate infectious propagules, the units that transmit a disease. These can refer to bacteria, viruses, fungi, or protists, and can be contained within host material. For instance, for influenza, the infectious propagules are carried in droplets of host saliva or mucus that are expelled during coughing or sneezing. In horticulture, a propagule is any plant material used for the purpose of plant propagation. In asexual reproduction, a propagule is often a stem cutting. In some plants, a leaf section or a portion of root can be used. In sexual reproduction, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sporulation
In biology, a spore is a unit of sexual or asexual reproduction that may be adapted for dispersal and for survival, often for extended periods of time, in unfavourable conditions. Spores form part of the life cycles of many plants, algae, fungi and protozoa. Bacterial spores are not part of a sexual cycle, but are resistant structures used for survival under unfavourable conditions. Myxozoan spores release amoeboid infectious germs ("amoebulae") into their hosts for parasitic infection, but also reproduce within the hosts through the pairing of two nuclei within the plasmodium, which develops from the amoebula. In plants, spores are usually haploid and unicellular and are produced by meiosis in the sporangium of a diploid sporophyte. Under favourable conditions the spore can develop into a new organism using mitotic division, producing a multicellular gametophyte, which eventually goes on to produce gametes. Two gametes fuse to form a zygote which develops into a new sporo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cultivar
A cultivar is a type of cultivated plant that people have selected for desired traits and when propagated retain those traits. Methods used to propagate cultivars include: division, root and stem cuttings, offsets, grafting, tissue culture, or carefully controlled seed production. Most cultivars arise from purposeful human 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'': 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 share the unique characteristics that define the cultivar. was coined as a term meaning "cultivated variety ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Strobilurin
Strobilurins are a group of natural products and their synthetic analogs. A number of strobilurins are used in agriculture as fungicides. They are part of the larger group of QIs (Quinone outside Inhibitors), which act to inhibit the respiratory chain at the level of Complex III. The first parent natural products, strobilurins A and B, were extracted from the fungus ''Strobilurus tenacellus''. Commercial strobilurin fungicides were developed through optimization of photostability and activity. Strobilurins represented a major development in fungus-based fungicides. First released in 1996, there are now ten major strobilurin fungicides on the market, which account for 23-25 % of the global fungicide sales. Examples of commercialized strobilurin derivatives are azoxystrobin, kresoxim-methyl, picoxystrobin, fluoxastrobin, oryzastrobin, dimoxystrobin, pyraclostrobin and trifloxystrobin. Strobilurins are mostly contact fungicides with a long half time as they are absorbed into the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyraclostrobin
Pyraclostrobin is a quinone outside inhibitor ( QI)-type fungicide used in agriculture. Among the QIs, it lies within the strobilurin chemical class. Use Pyraclostrobin is used to protect ''Fragaria'', ''Rubus idaeus'', ''Vaccinium corymbosum'', ''Ribes rubrum'', ''Ribes uva-crispa'', blackberry (various ''Rubus'' spp.), and '' Pistachio vera''. Target pathogens Pyraclostrobin is used against ''Botrytis cinerea'' and ''Alternaria alternata''. Resistance Resistant populations have been identified in: *''Botrytis cinerea'' on ''Fragaria'' in the Carolinas, conferred by the G143A mutation in the partial cytochrome b (CYTB) gene. *''Botrytis cinerea'' on ''Fragaria'', ''Rubus idaeus'', ''Vaccinium corymbosum'', ''Ribes rubrum'', ''Ribes uva-crispa'', and blackberry (various ''Rubus'' spp.) in Northern Germany. *''Botrytis cinerea'' on ''Fragaria'' in Florida. *''Alternaria alternata'' on '' Pistachio vera'' in California. Geography of use United States Pyraclostrobin was widely use ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ergosterol
Ergosterol (ergosta-5,7,22-trien-3β-ol) is a sterol found in cell membranes of fungi and protozoa, serving many of the same functions that cholesterol serves in animal cells. Because many fungi and protozoa cannot survive without ergosterol, the enzymes that synthesize it have become important targets for drug discovery. In human nutrition, ergosterol is a provitamin form of vitamin D2; exposure to ultraviolet (UV) light causes a chemical reaction that produces vitamin D2. Role in fungi Ergosterol (ergosta-5,7,22-trien-3β-ol) is a sterol found in fungi, and named for ergot, the common name of members of the fungal genus '' Claviceps'' from which ergosterol was first isolated. Ergosterol is a component of yeast and other fungal cell membranes, serving many of the same functions that cholesterol serves in animal cells. Its specificity in higher fungi is thought to be related to the climatic instabilities (highly varying humidity and moisture conditions) encountered by these orga ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tebuconazole
Tebuconazole is a triazole fungicide used agriculturally to treat plant pathogenic fungi. Environmental Hazards Though the U.S. Food and Drug Administration considers this fungicide to be safe for humans, it may still pose a risk. It is listed as a possible carcinogen in the United States Environmental Protection Agency Office of Pesticide Programs carcinogen list with a rating of C (possible carcinogen). Its acute toxicity is moderate. According to the World Health Organization The World Health Organization (WHO) is a specialized agency of the United Nations responsible for international public health. The WHO Constitution states its main objective as "the attainment by all peoples of the highest possible level of h ... toxicity classification, it is listed as III, which means slightly hazardous. Due to the potential for endocrine-disrupting effects, tebuconazole was assessed by the Swedish Chemicals Agency as being potentially removed from the market by EU regulation 1107 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chlorothalonil
Chlorothalonil (2,4,5,6-tetrachloroisophthalonitrile) is an organic compound mainly used as a broad spectrum, nonsystemic fungicide, with other uses as a wood protectant, pesticide, acaricide, and to control mold, mildew, bacteria, algae. Chlorothalonil-containing products are sold under the names Bravo, Echo, and Daconil. It was first registered for use in the US in 1966. In 1997, the most recent year for which data are available, it was the third most used fungicide in the US, behind only sulfur and copper, with used in agriculture that year. Including nonagricultural uses, the United States Environmental Protection Agency (EPA) estimates, on average, almost were used annually from 1990 to 1996.Reregistration Eligibility Decision for chlorothalonil US EPA, 1999. < ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Strip-till
Strip-till is a conservation system that uses a minimum tillage. It combines the soil drying and warming benefits of conventional tillage with the soil-protecting advantages of no-till by disturbing only the portion of the soil that is to contain the seed row. This type of tillage is performed with special equipment and can require the farmer to make multiple trips, depending on the strip-till implement used, and field conditions. Each row that has been strip-tilled is usually about eight to ten inches wide. Differences in the equipment used No-till planters have a disk opener and/or Coulter (agriculture) that is located in front of the planting unit. This coulter is designed to cut through crop residue and into the hard crust of the soil. After the coulter has broken through the residue and crust, the disk opener of the planting unit slices the soil and the seed is dropped into the furrow that has been created and then a press wheel closes the furrow. With strip-tillage syste ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fungicide
Fungicides are biocidal chemical compounds or biological organisms used to kill parasitic fungi or their spores. A fungistatic inhibits their growth. Fungi can cause serious damage in agriculture, resulting in critical losses of yield, quality, and profit. Fungicides are used both in agriculture and to fight fungal infections in animals. Chemicals used to control oomycetes, which are not fungi, are also referred to as fungicides, as oomycetes use the same mechanisms as fungi to infect plants. Fungicides can either be contact, translaminar or systemic. Contact fungicides are not taken up into the plant tissue and protect only the plant where the spray is deposited. Translaminar fungicides redistribute the fungicide from the upper, sprayed leaf surface to the lower, unsprayed surface. Systemic fungicides are taken up and redistributed through the xylem vessels. Few fungicides move to all parts of a plant. Some are locally systemic, and some move upwardly. Most fungicides that can ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Conidium
A conidium ( ; ), sometimes termed an asexual chlamydospore or chlamydoconidium (), is an asexual, non-motile spore of a fungus. The word ''conidium'' comes from the Ancient Greek word for dust, ('). They are also called mitospores due to the way they are generated through the cellular process of mitosis. The two new haploid cells are genetically identical to the haploid parent, and can develop into new organisms if conditions are favorable, and serve in biological dispersal. Asexual reproduction in ascomycetes (the phylum Ascomycota) is by the formation of conidia, which are borne on specialized stalks called conidiophores. The morphology of these specialized conidiophores is often distinctive between species and, before the development of molecular techniques at the end of the 20th century, was widely used for identification of (''e.g.'' ''Metarhizium'') species. The terms microconidia and macroconidia are sometimes used. Conidiogenesis There are two main types of co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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