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61-552: Environmental biotechnology can simply be described as "the optimal use of nature, in the form of plants , animals , bacteria , fungi and algae , to produce renewable energy , food and nutrients in a synergistic integrated cycle of profit making processes where the waste of each process becomes the feedstock for another process". The IAASTD has called for the advancement of small-scale agro-ecological farming systems and technology in order to achieve food security , climate change mitigation , climate change adaptation and

122-432: A few exemptions. Microorganisms from the polluted site are scan for genomic changes that allow them to degrade/utilize the starch better than other microbes of the same genus. The modified genes are then identified. The resultant genes are cloned into industrially significant microorganisms and are used for economically processes like in pharmaceutical industry, fermentations... etc.. Similar situations can be encountered in

183-405: A few or just one species. Beech drops ( Epifagus virginiana ) is a root holoparasite only on American beech ( Fagus grandifolia ). Rafflesia is a holoparasite on the vine Tetrastigma . Plants such as Pterospora become parasites of mycorrhizal fungi. There is evidence that parasites also practice self-discrimination, species of Triphysaria experience reduced haustorium development in

244-621: A few representatives. One example is the North American Monotropa uniflora (Indian pipe or corpse plant) which is a member of the heath family, Ericaceae , better known for its member blueberries, cranberries, and rhododendrons . Parasitic plants are characterized as follows: For hemiparasites, one from each of the three sets of terms can be applied to the same species, e.g. Holoparasites are always obligate so only two terms are needed, e.g. Plants usually considered holoparasites include broomrape , dodder , Rafflesia , and

305-581: A higher proportion of marine flora in temperate rather than tropical waters. While no full explanation for this is available, many of the potential host plants such as kelp and other macroscopic brown algae are generally restricted to temperate areas. Roughly 75% of parasitic red algae infect hosts in the same taxonomic family as themselves, these are given the designation adelphoparasites. Other marine parasites, deemed endozoic, are parasites of marine invertebrates ( mollusks , flatworms , sponges ) and can be either holoparasitic or hemiparasitic, some retaining

366-492: A host plant due to the presence of a parasitic plant. Often there is a pattern of stunted growth in hosts especially in hemi-parasitic cases, but may also result in higher mortality rates in host plant species following introduction of larger parasitic plant populations. Parasitic plants occur in multiple plant families, indicating that the evolution is polyphyletic . Some families consist mostly of parasitic representatives such as Balanophoraceae , while other families have only

427-410: A host plant. Using the resources in the seed endosperm , the dodder can germinate. Once germinated, the plant has 6 days to find and establish a connection with its host plant before its resources are exhausted. Dodder seeds germinate above ground, then the plant sends out stems in search of its host plant reaching up to 6  cm before it dies. It is believed that the plant uses two methods of finding

488-417: A host. The stem detects its host plant's scent and orients itself in that direction. Scientists used volatiles from tomato plants ( α-pinene , β-myrcene , and β-phellandrene ) to test the reaction of C. pentagona and found that the stem orients itself in the direction of the odor. Some studies suggest that by using light reflecting from nearby plants dodders can select hosts with higher sugar because of

549-545: A protective response. The first such plant receptors were identified in rice and in Arabidopsis thaliana . Plants have some of the largest genomes of all organisms. The largest plant genome (in terms of gene number) is that of wheat ( Triticum aestivum ), predicted to encode ≈94,000 genes and thus almost 5 times as many as the human genome . The first plant genome sequenced was that of Arabidopsis thaliana which encodes about 25,500 genes. In terms of sheer DNA sequence,

610-420: A range of physical and biotic stresses which cause DNA damage , but they can tolerate and repair much of this damage. Plants reproduce to generate offspring, whether sexually , involving gametes , or asexually , involving ordinary growth. Many plants use both mechanisms. When reproducing sexually, plants have complex lifecycles involving alternation of generations . One generation, the sporophyte , which

671-485: A variety of chemical germination stimulants. Strigol was the first of the germination stimulants to be isolated. It was isolated from a non-host cotton plant and has been found in true host plants such as corn and millets. The stimulants are usually plant-specific, examples of other germination stimulants include sorgolactone from sorghum, Orobanche and electoral from red clover, and 5-deoxystrigol from Lotus japonicus . Strigolactones are apocarotenoids that are produced via

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732-404: Is diploid (with 2 sets of chromosomes ), gives rise to the next generation, the gametophyte , which is haploid (with one set of chromosomes). Some plants also reproduce asexually via spores . In some non-flowering plants such as mosses, the sexual gametophyte forms most of the visible plant. In seed plants (gymnosperms and flowering plants), the sporophyte forms most of the visible plant, and

793-436: Is a plant that derives some or all of its nutritional requirements from another living plant. They make up about 1% of angiosperms and are found in almost every biome . All parasitic plants develop a specialized organ called the haustorium , which penetrates the host plant, connecting them to the host vasculature – either the xylem , phloem , or both. For example, plants like Striga or Rhinanthus connect only to

854-495: Is a mutant Sequoia sempervirens that produces no chlorophyll; they live on sugars from neighbouring trees, usually the parent tree from which they have grown (via a somatic mutation). Parasitic plants germinate in several methods. These can either be chemical or mechanical and the means used by seeds often depends on whether or not the parasites are root parasites or stem parasites. Most parasitic plants need to germinate near their host plants because their seeds are limited in

915-547: Is a similar process. Structures such as runners enable plants to grow to cover an area, forming a clone . Many plants grow food storage structures such as tubers or bulbs which may each develop into a new plant. Some non-flowering plants, such as many liverworts, mosses and some clubmosses, along with a few flowering plants, grow small clumps of cells called gemmae which can detach and grow. Plants use pattern-recognition receptors to recognize pathogens such as bacteria that cause plant diseases. This recognition triggers

976-404: Is about the balance between the applications that provide for these and the implications of manipulating genetic material. Textbooks address both the applications and implications. Environmental engineering texts addressing sewage treatment and biological principles are often now considered to be environmental biotechnology texts. These generally address the applications of biotechnologies, whereas

1037-496: Is known as botany , a branch of biology . All living things were traditionally placed into one of two groups, plants and animals . This classification dates from Aristotle (384–322 BC), who distinguished different levels of beings in his biology , based on whether living things had a "sensitive soul" or like plants only a "vegetative soul". Theophrastus , Aristotle's student, continued his work in plant taxonomy and classification. Much later, Linnaeus (1707–1778) created

1098-449: Is the name given to plants/algae that use rocks or boulders for attachment), while not necessarily parasitic, some species occur in high correlation with a certain host species, suggesting that they rely on the host plant in some way or another. In contrast, endophytic plants and algae grow inside their host plant, these have a wide range of host dependence from obligate holoparasites to facultative hemiparasites. Marine parasites occur as

1159-602: The Antarctic flora , consisting of algae, mosses, liverworts, lichens, and just two flowering plants, have adapted to the prevailing conditions on that southern continent. Plants are often the dominant physical and structural component of the habitats where they occur. Many of the Earth's biomes are named for the type of vegetation because plants are the dominant organisms in those biomes, such as grassland , savanna , and tropical rainforest . Parasitic plant A parasitic plant

1220-679: The Cretaceous so rapid that Darwin called it an " abominable mystery ". Conifers diversified from the Late Triassic onwards, and became a dominant part of floras in the Jurassic . In 2019, a phylogeny based on genomes and transcriptomes from 1,153 plant species was proposed. The placing of algal groups is supported by phylogenies based on genomes from the Mesostigmatophyceae and Chlorokybophyceae that have since been sequenced. Both

1281-476: The Hydnoraceae . Plants usually considered hemiparasites include Castilleja , mistletoe , Western Australian Christmas tree , and yellow rattle . Parasitic behavior evolved in angiosperms roughly 12-13 times independently, a classic example of convergent evolution . Roughly 1% of all angiosperm species are parasitic, with a large degree of host dependence. The taxonomic family Orobanchaceae (encompassing

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1342-457: The carpels or ovaries , which develop into fruits that contain seeds . Fruits may be dispersed whole, or they may split open and the seeds dispersed individually. Plants reproduce asexually by growing any of a wide variety of structures capable of growing into new plants. At the simplest, plants such as mosses or liverworts may be broken into pieces, each of which may regrow into whole plants. The propagation of flowering plants by cuttings

1403-751: The glaucophytes , in the clade Archaeplastida . There are about 380,000 known species of plants, of which the majority, some 260,000, produce seeds . They range in size from single cells to the tallest trees . Green plants provide a substantial proportion of the world's molecular oxygen; the sugars they create supply the energy for most of Earth's ecosystems and other organisms , including animals, either eat plants directly or rely on organisms which do so. Grain , fruit , and vegetables are basic human foods and have been domesticated for millennia. People use plants for many purposes , such as building materials , ornaments, writing materials , and, in great variety, for medicines . The scientific study of plants

1464-1003: The "chlorophyte algae" and the "streptophyte algae" are treated as paraphyletic (vertical bars beside phylogenetic tree diagram) in this analysis, as the land plants arose from within those groups. The classification of Bryophyta is supported both by Puttick et al. 2018, and by phylogenies involving the hornwort genomes that have also since been sequenced. Rhodophyta [REDACTED] Glaucophyta [REDACTED] Chlorophyta [REDACTED] Prasinococcales   Mesostigmatophyceae Chlorokybophyceae Spirotaenia [REDACTED] Klebsormidiales [REDACTED] Chara [REDACTED] Coleochaetales [REDACTED] Hornworts [REDACTED] Liverworts [REDACTED] Mosses [REDACTED] Lycophytes [REDACTED] [REDACTED] Gymnosperms [REDACTED] Angiosperms [REDACTED] Plant cells have distinctive features that other eukaryotic cells (such as those of animals) lack. These include

1525-448: The ability to become associated with many of the other plants around them. They are termed myco-heterotrophs . Some myco-heterotrophs are Indian pipe ( Monotropa uniflora ), snow plant ( Sarcodes sanguinea ), underground orchid ( Rhizanthella gardneri ), bird's nest orchid ( Neottia nidus-avis ), and sugarstick ( Allotropa virgata ). Within the taxonomic family Ericaceae , known for extensive mycorrhizal relationships, there are

1586-557: The ability to photosynthesize after infection. These are the only parasitic plants that parasitize animal hosts. Species within Orobanchaceae are some of the most economically destructive species on Earth. Species of Striga alone are estimated to cost billions of dollars a year in crop yield loss annually, infesting over 50 million hectares of cultivated land within sub-Saharan Africa alone. Striga can infest both grasses and grains, including corn , rice and sorghum , some of

1647-801: The amount of cytoplasm stays the same. Most plants are multicellular . Plant cells differentiate into multiple cell types, forming tissues such as the vascular tissue with specialized xylem and phloem of leaf veins and stems , and organs with different physiological functions such as roots to absorb water and minerals, stems for support and to transport water and synthesized molecules, leaves for photosynthesis, and flowers for reproduction. Plants photosynthesize , manufacturing food molecules ( sugars ) using energy obtained from light . Plant cells contain chlorophylls inside their chloroplasts, which are green pigments that are used to capture light energy. The end-to-end chemical equation for photosynthesis is: This causes plants to release oxygen into

1708-431: The atmosphere. Green plants provide a substantial proportion of the world's molecular oxygen, alongside the contributions from photosynthetic algae and cyanobacteria. Plants that have secondarily adopted a parasitic lifestyle may lose the genes involved in photosynthesis and the production of chlorophyll. Growth is determined by the interaction of a plant's genome with its physical and biotic environment. Factors of

1769-461: The basis of the modern system of scientific classification , but retained the animal and plant kingdoms , naming the plant kingdom the Vegetabilia. When the name Plantae or plant is applied to a specific group of organisms or taxa , it usually refers to one of four concepts. From least to most inclusive, these four groupings are: There are about 382,000 accepted species of plants, of which

1830-438: The carotenoid pathway of plants. Strigolactones and mycorrhizal fungi have a relationship in which Strigolactone also cues the growth of mycorrhizal fungus. Stem parasitic plants, unlike most root parasites, germinate using the resources inside their endosperms and can survive for some time. For example, the dodders ( Cuscuta spp.) drop their seeds to the ground. These may remain dormant for up to five years before they find

1891-545: The case of marine oil spills which require cleanup, where microbes isolated from oil rich environments like oil wells, oil transfer pipelines...etc. have been found having the potential to degrade oil or use it as an energy source. Thus they serve as a remedy to oil spills. Microbes isolated from pesticide - contaminated soils may capable of utilizing the pesticides as energy source and hence when mixed along with bio-fertilizers, could serve as an insurance against increased pesticide-toxicity levels in agricultural platform. On

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1952-739: The community. Parasitic plants are major shapers of their community, affecting not just the host species but indirectly affecting others. Competition amongst host species will change due to the parasitic plant. Plant parasitism have been shown to keep invasive species under control and become keystone species in an ecosystem. In many regions, including the Nepal Eastern Himalayas , parasitic plants are used for medicinal and ritual purposes. About 400 species of flowering plants, plus one gymnosperm ( Parasitaxus usta ) and one bryophyte (the liverwort Aneura mirabilis ), are parasitic on mycorrhizal fungi. This effectively gives these plants

2013-411: The control of Orobanche and Striga species, which are even more devastating in developing areas of the world, though no method has been found to be entirely successful. Some parasitic plants are destructive while some have positive influences in their communities . Some parasitic plants damage invasive species more than native species . This results in the reduced damage of invasive species in

2074-483: The development of forests in swampy environments dominated by clubmosses and horsetails, including some as large as trees, and the appearance of early gymnosperms , the first seed plants . The Permo-Triassic extinction event radically changed the structures of communities. This may have set the scene for the evolution of flowering plants in the Triassic (~ 200  million years ago ), with an adaptive radiation in

2135-510: The facultative hemiparasites within Triphysaria , lateral haustoria develop along the surface of the roots in these species. Later evolution led to the development of terminal or primary haustoria at the tip of the juvenile radicle , seen in obligate hemiparasitic species within Striga . Lastly, holoparasitic plants, always forms of obligate parasites, evolved over the loss of photosynthesis, seen in

2196-471: The fungi and some of the algae. By the definition used in this article, plants form the clade Viridiplantae (green plants), which consists of the green algae and the embryophytes or land plants ( hornworts , liverworts , mosses , lycophytes , ferns , conifers and other gymnosperms , and flowering plants ). A definition based on genomes includes the Viridiplantae, along with the red algae and

2257-409: The gametophyte is very small. Flowering plants reproduce sexually using flowers, which contain male and female parts: these may be within the same ( hermaphrodite ) flower, on different flowers on the same plant , or on different plants . The stamens create pollen , which produces male gametes that enter the ovule to fertilize the egg cell of the female gametophyte. Fertilization takes place within

2318-455: The genera Triphysaria , Striga , and Orobanche ) is the only family that contains both holoparasitic and hemiparasitic species, making it a model group for studying the evolutionary rise of parasitism . The remaining groups contain only hemiparasites or holoparasites. The evolutionary event which gave rise to parasitism in plants was the development of haustoria . The first, most ancestral, haustoria are thought to be similar to that of

2379-607: The genus Orobanche . The most specialized forms of holoparasitic plants are the four families Rafflesiaceae , Cytinaceae , Mitrastemonaceae and Apodanthaceae , lineages which independently has evolved further into endoparasites that, except for the flowers, spend their entire life cycle within the tissue of their host. To maximize resources, many parasitic plants have evolved 'self-incompatibility', to avoid parasitizing themselves. Others such as Triphysaria usually avoid parasitizing other members of their species, but some parasitic plants have no such limits. The albino redwood

2440-575: The great majority, some 283,000, produce seeds . The table below shows some species count estimates of different green plant (Viridiplantae) divisions . About 85–90% of all plants are flowering plants. Several projects are currently attempting to collect records on all plant species in online databases, e.g. the World Flora Online . Plants range in scale from single-celled organisms such as desmids (from 10  micrometres   (μm) across) and picozoa (less than 3 μm across), to

2501-510: The green pigment chlorophyll . Exceptions are parasitic plants that have lost the genes for chlorophyll and photosynthesis, and obtain their energy from other plants or fungi. Most plants are multicellular , except for some green algae. Historically, as in Aristotle's biology , the plant kingdom encompassed all living things that were not animals , and included algae and fungi . Definitions have narrowed since then; current definitions exclude

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2562-417: The host (root or stem), the amount of nutrients it requires, and their photosynthetic capability. Some parasitic plants can locate their host plants by detecting volatile chemicals in the air or soil given off by host shoots or roots , respectively. About 4,500 species of parasitic plants in approximately 20 families of flowering plants are known. There is a wide range of effects that may occur to

2623-472: The implications of these technologies are less often addressed; usually in books concerned with potential impacts and even catastrophic events. Plant See text Plants are the eukaryotes that form the kingdom Plantae ; they are predominantly photosynthetic . This means that they obtain their energy from sunlight , using chloroplasts derived from endosymbiosis with cyanobacteria to produce sugars from carbon dioxide and water, using

2684-517: The land 1,200  million years ago , but it was not until the Ordovician , around 450  million years ago , that the first land plants appeared, with a level of organisation like that of bryophytes. However, fossils of organisms with a flattened thallus in Precambrian rocks suggest that multicellular freshwater eukaryotes existed over 1000 mya. Primitive land plants began to diversify in

2745-412: The large water-filled central vacuole , chloroplasts , and the strong flexible cell wall , which is outside the cell membrane . Chloroplasts are derived from what was once a symbiosis of a non-photosynthetic cell and photosynthetic cyanobacteria . The cell wall, made mostly of cellulose , allows plant cells to swell up with water without bursting. The vacuole allows the cell to change in size while

2806-507: The largest trees ( megaflora ) such as the conifer Sequoia sempervirens (up to 120 metres (380 ft) tall) and the angiosperm Eucalyptus regnans (up to 100 m (325 ft) tall). The naming of plants is governed by the International Code of Nomenclature for algae, fungi, and plants and the International Code of Nomenclature for Cultivated Plants . The ancestors of land plants evolved in water. An algal scum formed on

2867-656: The late Silurian , around 420  million years ago . Bryophytes, club mosses, and ferns then appear in the fossil record. Early plant anatomy is preserved in cellular detail in an early Devonian fossil assemblage from the Rhynie chert . These early plants were preserved by being petrified in chert formed in silica-rich volcanic hot springs. By the end of the Devonian, most of the basic features of plants today were present, including roots, leaves and secondary wood in trees such as Archaeopteris . The Carboniferous period saw

2928-412: The levels of chlorophyll in the leaves. Once the dodder finds its host, it wraps itself around the host plant's stem. Using adventitious roots, the dodder taps into the host plant's stem with a haustorium , an absorptive organ within the host plant vascular tissue . Dodder makes several of these connections with the host as it moves up the plant. There are several methods of seed dispersal, but all

2989-434: The most important food crops. Orobanche also threatens a wide range of important crops, including peas, chickpeas , tomatoes , carrots , lettuce , and varieties of the genus Brassica (e.g. cabbage and broccoli). Yield loss from Orobanche can reach 100% and has caused farmers in some regions of the world to abandon certain staple crops and begin importing others as an alternative. Much research has been devoted to

3050-408: The number of resources necessary to survive without nutrients from their host plants. Resources are limited due in part to the fact that most parasitic plants are not able to use autotrophic nutrition to establish the early stages of seeding. Root parasitic plant seeds tend to use chemical cues for germination. For germination to occur, seeds need to be quite close to the host plant. For example,

3111-695: The other hand, these newly introduced microorganisms could create an imbalance in the environment concerned. The mutual harmony in which the organisms in that particular environment existed may have to face alteration and we should be extremely careful so as to not disturb the mutual relationships already existing in the environment of both the benefits and the disadvantages would pave way for an improvised version of environmental biotechnology. Humans have long been manipulating genetic material through breeding and modern genetic modification for optimizing crop yield , etc.. There can also be unexpected, negative health and environmental outcomes. Environmental biotechnology

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3172-433: The parasitic plant, eventually killing it. The fourth hurdle is the host's ability to ruin the tubercle using gums and gels or injecting toxins into the tubercle . Some parasitic plants are generalists and parasitize many different species, even several different species at once. Dodder ( Cuscuta spp.) and red rattle ( Odontites vernus ) are generalist parasites. Other parasitic plants are specialists that parasitize

3233-407: The parasitic progress at the cortex of the host's roots. The second hurdle is the host's ability to secrete germination inhibitors. This prevents germination of the parasitic seed. The third hurdle is the host's ability to create a toxic environment at the location where the parasitic plant attaches. The host secretes phenolic compounds into the apoplast . This creates a toxic environment for

3294-501: The physical or abiotic environment include temperature , water , light, carbon dioxide , and nutrients in the soil. Biotic factors that affect plant growth include crowding, grazing, beneficial symbiotic bacteria and fungi, and attacks by insects or plant diseases . Frost and dehydration can damage or kill plants. Some plants have antifreeze proteins , heat-shock proteins and sugars in their cytoplasm that enable them to tolerate these stresses . Plants are continuously exposed to

3355-422: The presence of other Triphysaria . The mechanism for self-discrimination in parasites is not yet known. Parasitism also evolved within aquatic species of plants and algae. Parasitic marine plants are described as benthic , meaning that they are sedentary or attached to another structure. Plants and algae that grow on the host plant, using it as an attachment point are given the designation epiphytic ( epilithic

3416-560: The realisation of the Millennium Development Goals . Environmental biotechnology has been shown to play a significant role in agroecology in the form of zero waste agriculture and most significantly through the operation of over 15 million biogas digesters worldwide. Consider the effluents of starch plant which has mixed up with a local water body like a lake or pond. We find huge deposits of starch which are not so easily taken up for degradation by microorganisms except for

3477-414: The seeds of witchweed ( Striga asiatica ) need to be within 3 to 4 millimeters (mm) of its host to receive chemical signals in the soil to trigger germination. This range is important because Striga Asiatica will only grow about 4  mm after germination. Chemical compound cues sensed by parasitic plant seeds are from host plant root exudates that are leached nearby from the host's root system into

3538-465: The smallest published genome is that of the carnivorous bladderwort ( Utricularia gibba) at 82 Mb (although it still encodes 28,500 genes) while the largest, from the Norway spruce ( Picea abies ), extends over 19.6 Gb (encoding about 28,300 genes). Plants are distributed almost worldwide. While they inhabit several biomes which can be divided into a multitude of ecoregions , only the hardy plants of

3599-436: The strategies aim to put the seed in direct contact with, or within a critical distance of, the host. A parasitic plant has many obstacles to overcome to attach to a host. Distance from the host and stored nutrients are some of the problems, and the host's defenses are an obstacle to overcome. The first hurdle is penetrating the host since the host has systems to reinforce the cell wall by protein cross-linking so that it stops

3660-469: The surrounding soil. These chemical cues are a variety of compounds that are unstable and rapidly degraded in soil and are present within a radius of a few meters of the plant exuding them. Parasitic plants germinate and follow a concentration gradient of these compounds in the soil toward the host plants if close enough. These compounds are called strigolactones . Strigolactone stimulates ethylene biosynthesis in seeds causing them to germinate. There are

3721-409: The xylem, via xylem bridges (xylem-feeding). Alternately, plants like Cuscuta and some members of Orobanche connect to both the xylem and phloem of the host. This provides them with the ability to extract resources from the host. These resources can include water, nitrogen, carbon and/or sugars. Parasitic plants are classified depending on the location where the parasitic plant latches onto

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