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Gummy Stem Blight
Gummy stem blight is a cucurbit-rot disease caused by the fungal plant pathogen '' Didymella bryoniae'' (anamorph ''Phoma cucurbitacearum''). Gummy stem blight can affect a host at any stage of growth in its development and affects all parts of the host including leaves, stems and fruits. Symptoms generally consist of circular dark tan lesions that blight the leaf, water soaked leaves, stem cankers, and gummy brown ooze that exudes from cankers, giving it the name . Gummy stem blight reduces yields of edible cucurbits by devastating the vines and leaves and rotting the fruits. There are various methods to control gummy stem blight, including use of treated seed, crop rotation, using preventative fungicides, eradication of diseased material, and deep plowing previous debris. Hosts and symptoms Gummy stem blight affects many cucurbits including watermelon, cantaloupe, cucumber, pumpkin, and some squash. Some symptoms are common of all gummy stem blight infections while other symp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Didymella Bryoniae
''Didymella bryoniae,'' syn. ''Mycosphaerella melonis,'' is an ascomycete fungal plant pathogen that causes gummy stem blight on the family ''Cucurbitaceae'' (the family of gourds and melons), which includes cantaloupe, cucumber, muskmelon and watermelon plants. The anamorph/asexual stage for this fungus is called ''Phoma cucurbitacearum''. When this pathogen infects the fruit of cucurbits it is called black rot. Host symptoms * Gray-green to black circular leaf spots * Angular/target-like water-soaked lesions * Stem lesions/cankers * Vine lesions * Vine Necrosis * Reddish gummy ooze exuding from the lesions/wounds * Wilt * Defoliation The first symptoms appear as grayish green, circular spots between the veins of the leaf lobes. With age these spots darken to brown and black. Lesions begin to develop on vines at the vine nodes and then elongate into water-soaked streaks, and these streaks are pale brown at first but turn gray with time. The petioles and stems eventually become ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
University Of Kentucky
The University of Kentucky (UK, UKY, or U of K) is a Public University, public Land-grant University, land-grant research university in Lexington, Kentucky. Founded in 1865 by John Bryan Bowman as the Agricultural and Mechanical College of Kentucky, the university is one of the state's two land-grant universities (the other being Kentucky State University) and the institution with the highest enrollment in the state, with 30,545 students as of fall 2019. The institution comprises 16 colleges, a graduate school, 93 undergraduate programs, 99 master's degrees, master programs, 66 Doctor of Philosophy, doctoral programs, and four professional programs. It is Carnegie Classification of Institutions of Higher Education, classified among "R1: Doctoral Universities – Very high research activity". According to the National Science Foundation, Kentucky spent $393 million on research and development in 2018, ranking it 63rd in the nation. The University of Kentucky has fifteen libraries ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States
The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territories, nine Minor Outlying Islands, and 326 Indian reservations. The United States is also in free association with three Pacific Island sovereign states: the Federated States of Micronesia, the Marshall Islands, and the Republic of Palau. It is the world's third-largest country by both land and total area. It shares land borders with Canada to its north and with Mexico to its south and has maritime borders with the Bahamas, Cuba, Russia, and other nations. With a population of over 333 million, it is the most populous country in the Americas and the third most populous in the world. The national capital of the United States is Washington, D.C. and its most populous city and principal financial center is New York City. Paleo-Americ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Powdery Mildew
Powdery mildew is a fungal disease that affects a wide range of plants. Powdery mildew diseases are caused by many different species of ascomycete fungi in the order Erysiphales. Powdery mildew is one of the easier plant diseases to identify, as its symptoms are quite distinctive. Infected plants display white powdery spots on the leaves and stems. The lower leaves are the most affected, but the mildew can appear on any above-ground part of the plant. As the disease progresses, the spots get larger and denser as large numbers of asexual spores are formed, and the mildew may spread up and down the length of the plant. Powdery mildew grows well in environments with high humidity and moderate temperatures. Greenhouses provide an ideal moist, temperate environment for the spread of the disease. This causes harm to agricultural and horticultural practices where powdery mildew may thrive in a greenhouse setting. In an agricultural or horticultural setting, the pathogen can be controlle ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aphid
Aphids are small sap-sucking insects and members of the superfamily Aphidoidea. Common names include greenfly and blackfly, although individuals within a species can vary widely in color. The group includes the fluffy white woolly aphids. A typical life cycle involves flightless females giving live birth to female nymphs—who may also be already pregnant, an adaptation scientists call telescoping generations—without the involvement of males. Maturing rapidly, females breed profusely so that the number of these insects multiplies quickly. Winged females may develop later in the season, allowing the insects to colonize new plants. In temperate regions, a phase of sexual reproduction occurs in the autumn, with the insects often overwintering as eggs. The life cycle of some species involves an alternation between two species of host plants, for example between an annual crop and a woody plant. Some species feed on only one type of plant, while others are generalists, coloni ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Striped Cucumber Beetle
''Acalymma vittatum'', the striped cucumber beetle, is a beetle of the family Chrysomelidae and a serious pest of cucurbit crops in both larval and adult stages. It is distributed from eastern North America to the Rocky Mountains. It is replaced in the west by '' Acalymma trivittatum'', a duller species often with greyish or pale white elytra rather than yellow. Description The striped cucumber beetle is a small beetle approximately half a centimeter (1/5 inch) in length, and characterized by brown-yellow elytra completely covering the abdomen and longitudinally transversed by three thick black stripes. It superficially resembles the western corn rootworm (''Diabrotica virgifera''), another serious crop pest. However, the ventral abdominal surface of ''A. vittatum'' is black where that of ''D. virgifera'' are yellow, and the elytra of ''D. virgifera'' often do not extend the full length of the abdomen. Life cycle Large numbers of adults emerge from diapause in the spring to fe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Conidia
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 conidium ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mycelium
Mycelium (plural mycelia) is a root-like structure of a fungus consisting of a mass of branching, thread-like hyphae. Fungal colonies composed of mycelium are found in and on soil and many other substrate (biology), substrates. A typical single spore germinates into a Monokaryon, monokaryotic mycelium, which cannot reproduce sexually; when two compatible monokaryotic mycelia join and form a dikaryotic mycelium, that mycelium may form sporocarp (fungi), fruiting bodies such as mushrooms. A mycelium may be minute, forming a colony that is too small to see, or may grow to span thousands of acres as in ''Armillaria''. Through the mycelium, a fungus absorbs nutrients from its environment. It does this in a two-stage process. First, the hyphae secrete enzymes onto or into the food source, which break down biopolymers, biological polymers into smaller units such as monomers. These monomers are then absorbed into the mycelium by facilitated diffusion and active transport. Mycelia are v ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
University Of Minnesota Extension
The University of Minnesota system is a public university system with five campuses spread across the U.S. state of Minnesota. The university system has five campuses, in the Twin Cities, Crookston, Duluth, Morris, and Rochester. The university also operates several research facilities around the state, including some large parcels of land. The University of Minnesota Twin Cities, Crookston, Duluth, Morris and Rochester campuses are accredited by the Higher Learning Commission (HLC). The other public system of higher education in the state is the larger Minnesota State Colleges and Universities system (Minnesota State System, previously MnSCU) The university has one of the largest endowments among public universities in the U.S., and also receives annual funding from the State of Minnesota. Campuses The flagship Twin Cities campus is the largest in the system, with a total enrollment of 50,943 students (undergraduate, graduate, professional, and non-degree included) Crook ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Perithecia
An ascocarp, or ascoma (), is the fruiting body ( sporocarp) of an ascomycete phylum fungus. It consists of very tightly interwoven hyphae and millions of embedded asci, each of which typically contains four to eight ascospores. Ascocarps are most commonly bowl-shaped (apothecia) but may take on a spherical or flask-like form that has a pore opening to release spores (perithecia) or no opening (cleistothecia). Classification The ascocarp is classified according to its placement (in ways not fundamental to the basic taxonomy). It is called ''epigeous'' if it grows above ground, as with the morels, while underground ascocarps, such as truffles, are termed ''hypogeous''. The structure enclosing the hymenium is divided into the types described below (apothecium, cleistothecium, etc.) and this character ''is'' important for the taxonomic classification of the fungus. Apothecia can be relatively large and fleshy, whereas the others are microscopic—about the size of flecks of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pycnidia
A pycnidium (plural pycnidia) is an asexual fruiting body produced by mitosporic fungi, for instance in the order Sphaeropsidales ( Deuteromycota, Coelomycetes) or order Pleosporales (Ascomycota, Dothideomycetes). It is often spherical or inversely pearshaped ( obpyriform) and its internal cavity is lined with conidiophores. When ripe, an opening generally appears at the top, through which the pycnidiospore {{Short pages monitor [Baidu] |
Cotyledon
A cotyledon (; ; ; , gen. (), ) is a significant part of the embryo within the seed of a plant, and is defined as "the embryonic leaf in seed-bearing plants, one or more of which are the first to appear from a germinating seed." The number of cotyledons present is one characteristic used by botanists to classify the flowering plants (angiosperms). Species with one cotyledon are called monocotyledonous ("monocots"). Plants with two embryonic leaves are termed dicotyledonous ("dicots"). In the case of dicot seedlings whose cotyledons are photosynthetic, the cotyledons are functionally similar to leaves. However, true leaves and cotyledons are developmentally distinct. Cotyledons are formed during embryogenesis, along with the root and shoot meristems, and are therefore present in the seed prior to germination. True leaves, however, are formed post-embryonically (i.e. after germination) from the shoot apical meristem, which is responsible for generating subsequent aerial por ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
