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Entomophaga Grylli
''Entomophaga grylli'' is a fungal pathogen which infects and kills grasshoppers. It is the causal agent of one of the most widespread diseases affecting grasshoppers. This is sometimes known as summit disease because infected insects climb to the upper part of a plant and grip the tip of the stem as they die; this ensures widespread dispersal of the fungal spores. The fungus is a species complex with several different pathotypes, each one of which seems to be host-specific to different subfamilies of grasshoppers. The pathogen is being investigated for its possible use in biological pest control of grasshoppers. Taxonomy ''E. grylli'' is a species complex which in North America includes the pathotypes ''E. macleodii'' and ''E. calopteni'', and in Australia ''E. praxibuli''. The different pathotypes can be distinguished by the formation or lack of formation of primary conidia, the size and the number of nuclei in the conidia, their isozyme profiles, the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fungus
A fungus ( : fungi or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and molds, as well as the more familiar mushrooms. These organisms are classified as a kingdom, separately from the other eukaryotic kingdoms, which by one traditional classification include Plantae, Animalia, Protozoa, and Chromista. A characteristic that places fungi in a different kingdom from plants, bacteria, and some protists is chitin in their cell walls. Fungi, like animals, are heterotrophs; they acquire their food by absorbing dissolved molecules, typically by secreting digestive enzymes into their environment. Fungi do not photosynthesize. Growth is their means of mobility, except for spores (a few of which are flagellated), which may travel through the air or water. Fungi are the principal decomposers in ecological systems. These and other differences place fungi in a single group of related organisms, named the ''Eumycota'' (''tru ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Resting Spore
A resting spore is a resistant cell, used to survive adverse environmental conditions. Resting spore is a term commonly applied to both diatoms and fungi. In fungi A resting spore can be a spore created by fungi which is thickly encysted (has a thick cell wall) in order to survive through stressful times, such as drought. It protects the spore from biotic (microbial, fungal viral), as well as abiotic (wind, heat, xeric conditions) factors. Resting spores of a particular fungus are known create the phenomenon known as late potato blight. They can lie dormant within the soil of a field for decades until the right conditions occur for viability (plant host present, rain, fire etc.). In diatoms A similar resting spore life stage is also present in diatoms, and in such case, is also often referred to as the hypnospore. Importantly, the resting spore of marine diatoms is not an obligate stage of the life cycle, except in the minority of studied taxa, where spore production imme ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States Department Of Agriculture
The United States Department of Agriculture (USDA) is the federal executive department responsible for developing and executing federal laws related to farming, forestry, rural economic development, and food. It aims to meet the needs of commercial farming and livestock food production, promotes agricultural trade and production, works to assure food safety, protects natural resources, fosters rural communities and works to end hunger in the United States and internationally. It is headed by the Secretary of Agriculture, who reports directly to the President of the United States and is a member of the president's Cabinet. The current secretary is Tom Vilsack, who has served since February 24, 2021. Approximately 80% of the USDA's $141 billion budget goes to the Food and Nutrition Service (FNS) program. The largest component of the FNS budget is the Supplemental Nutrition Assistance Program (formerly known as the Food Stamp program), which is the cornerstone of USD ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Integrated Pest Management
Integrated pest management (IPM), also known as integrated pest control (IPC) is a broad-based approach that integrates both chemical and non-chemical practices for economic control of pests. IPM aims to suppress pest populations below the economic injury level (EIL). The UN's Food and Agriculture Organization defines IPM as "the careful consideration of all available pest control techniques and subsequent integration of appropriate measures that discourage the development of pest populations and keep pesticides and other interventions to levels that are economically justified and reduce or minimize risks to human health and the environment. IPM emphasizes the growth of a healthy crop with the least possible disruption to agro-ecosystems and encourages natural pest control mechanisms." Entomologists and ecologists have urged the adoption of IPM pest control since the 1970s. IPM allows for safer pest control. The introduction and spread of invasive species can also be managed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biological Exponential Growth
Biological exponential growth is the unrestricted growth of a population of organisms, occurring when resources in its habitat are unlimited. Most commonly apparent in species that reproduce quickly and asexually, like bacteria, exponential growth is intuitive from the fact that each organism can divide and produce two copies of itself. Each descendent bacterium can itself divide, again doubling the population size. The bacterium Escherichia coli, under optimal conditions, may divide as often as twice per hour. Left unrestricted, a colony would cover the Earth's surface in less than a day. If, in a hypothetical population of size ''N'', the birth rates (per capita) are represented as ''b'' and death rates (per capita) as ''d'', then the increase or decrease in ''N'' during a time period ''t'' will be \frac=(b-d)N (b-d) is called the 'intrinsic rate of natural increase' and is a very important parameter chosen for assessing the impacts of any biotic or abiotic factor on population ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Epizootic
In epizoology, an epizootic (from Greek: ''epi-'' upon + ''zoon'' animal) is a disease event in a nonhuman animal population analogous to an epidemic in humans. An epizootic may be restricted to a specific locale (an "outbreak"), general (an "epizootic"), or widespread ("panzootic"). High population density is a major contributing factor to epizootics. Aquaculture is an industry sometimes plagued by disease because of the large number of fish confined to a small area. Defining an epizootic can be subjective; it is based upon the number of new cases in a given animal population, during a given period, and must be judged to be a rate that substantially exceeds what is expected based on recent experience (''i.e.'' a sharp elevation in the incidence rate). Because it is based on what is "expected" or thought normal, a few cases of a very rare disease (like a transmissible spongiform encephalopathy outbreak in a cervid population) might be classified as an "epizootic", while many c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cadaver
A cadaver or corpse is a dead human body that is used by medical students, physicians and other scientists to study anatomy, identify disease sites, determine causes of death, and provide tissue to repair a defect in a living human being. Students in medical school study and dissect cadavers as a part of their education. Others who study cadavers include archaeologists and arts students. The term ''cadaver'' is used in courts of law (and, to a lesser extent, also by media outlets such as newspapers) to refer to a dead body, as well as by recovery teams searching for bodies in natural disasters. The word comes from the Latin word ''cadere'' ("to fall"). Related terms include ''cadaverous'' (resembling a cadaver) and ''cadaveric spasm'' (a muscle spasm causing a dead body to twitch or jerk). A cadaver graft (also called “postmortem graft”) is the grafting of tissue from a dead body onto a living human to repair a defect or disfigurement. Cadavers can be observed for their sta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Conidiophore
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 conidi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypha
A hypha (; ) is a long, branching, filamentous structure of a fungus, oomycete, or actinobacterium. In most fungi, hyphae are the main mode of vegetative growth, and are collectively called a mycelium. Structure A hypha consists of one or more cells surrounded by a tubular cell wall. In most fungi, hyphae are divided into cells by internal cross-walls called "septa" (singular septum). Septa are usually perforated by pores large enough for ribosomes, mitochondria, and sometimes nuclei to flow between cells. The major structural polymer in fungal cell walls is typically chitin, in contrast to plants and oomycetes that have cellulosic cell walls. Some fungi have aseptate hyphae, meaning their hyphae are not partitioned by septa. Hyphae have an average diameter of 4–6 µm. Growth Hyphae grow at their tips. During tip growth, cell walls are extended by the external assembly and polymerization of cell wall components, and the internal production of new cell membrane. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Immune System
The immune system is a network of biological processes that protects an organism from diseases. It detects and responds to a wide variety of pathogens, from viruses to parasitic worms, as well as cancer cells and objects such as wood splinters, distinguishing them from the organism's own healthy tissue. Many species have two major subsystems of the immune system. The innate immune system provides a preconfigured response to broad groups of situations and stimuli. The adaptive immune system provides a tailored response to each stimulus by learning to recognize molecules it has previously encountered. Both use molecules and cells to perform their functions. Nearly all organisms have some kind of immune system. Bacteria have a rudimentary immune system in the form of enzymes that protect against virus infections. Other basic immune mechanisms evolved in ancient plants and animals and remain in their modern descendants. These mechanisms include phagocytosis, antimicrobial ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protoplast
Protoplast (), is a biological term coined by Hanstein in 1880 to refer to the entire cell, excluding the cell wall. Protoplasts can be generated by stripping the cell wall from plant, bacterial, or fungal cells by mechanical, chemical or enzymatic means. Protoplasts differ from spheroplasts in that their cell wall has been completely removed. Spheroplasts retain part of their cell wall. In the case of Gram-negative bacterial spheroplasts, for example, the peptidoglycan component of the cell wall has been removed but the outer membrane component has not. Enzymes for the preparation of protoplasts Cell walls are made of a variety of polysaccharides. Protoplasts can be made by degrading cell walls with a mixture of the appropriate polysaccharide-degrading enzymes: During and subsequent to digestion of the cell wall, the protoplast becomes very sensitive to osmotic stress. This means cell wall digestion and protoplast storage must be done in an isotonic solution to pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hemocoel
The blood circulatory system is a system of organs that includes the heart, blood vessels, and blood which is circulated throughout the entire body of a human or other vertebrate. It includes the cardiovascular system, or vascular system, that consists of the heart and blood vessels (from Greek ''kardia'' meaning ''heart'', and from Latin ''vascula'' meaning ''vessels''). The circulatory system has two divisions, a systemic circulation or circuit, and a pulmonary circulation or circuit. Some sources use the terms ''cardiovascular system'' and ''vascular system'' interchangeably with the ''circulatory system''. The network of blood vessels are the great vessels of the heart including large elastic arteries, and large veins; other arteries, smaller arterioles, capillaries that join with venules (small veins), and other veins. The circulatory system is closed in vertebrates, which means that the blood never leaves the network of blood vessels. Some invertebrates such as arthr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
