Duckweed is a very easy plant to grow and performs a double service of recycling nutrients from various sources of biomass. Here, we analyse genomic sequences of the highly asexual aquatic duckweed, Spirodela polyrhiza. More often, species propagate asexually by … Duckweed is very prolific, and given enough nitrogen and phosphorus nutrients, it is possible for a new duckweed plant to be produced every 24 hours. A continuously growing plant like Duckweed exhibits well the characteristic phases of population growth. You should also add fertilizer to the water to encourage it to reproduce by itself without any help from you. Thus, artificial mutagenesis and molecular breeding are preferable for duckweed breeding, which dramatically shorten the … Duckweed grows best in well-lighted areas but not direct sunlight and can reproduce rapidly when conditions are ideal. Once mature, they are herbivorous and will consume most species of floating plants such as duckweed. From this occasional reproduction is produced a seed in an air bag that floats. The duckweed was raised in 5 gal (18.93 L) containers using domestic water (Jenks, OK) treated with Aqueon Water Conditioner (5401 W. Oakwood Park Dr., Franklin, WI 53132, aqueonproducts.com). How to Grow Duckweed IndoorsCover the outside of the aquarium with black contact paper. ...Place the aquarium in a warm, sunny location where it receives at least six hours of sunlight daily.Install an airstone and small pump to keep the water oxygenated. ...Fill the aquarium with pond water if possible. ...More items... Minute Duckweed (Lemna perpusilla) is on the "watch list." Brush all the duckweed off the outside. In some cases, duckweed can be a boon. Duckweeds, because of their extensive proliferation on fresh water surfaces, reduce evaporation and prevent algal, bacterial, and mosquito growth. I have Duckweed can be used to feed fish, poultry and cattle (PRISM, INC) . 1.6 Approach First, a literature research will be done on the duckweed species that are cultivated at the Ecoferm greenhouse. Overall, this is an easy plant to grow and … 2 As each frond matures, it begins producing new buds in the meristematic zone near the center of the frond. Generally, the reproduction rate of duckweed and watermeal are astounding given the right nutrient load in the water. Duckweed Information. I don't know why mine would not catch on in my nutrient rich pond. These authors contributed equally to this work. How Does Duckweed Reproduce? Duckweed may be a way to create a bio-fuel without harming the environment. In this research the basics of photosynthesis will be discussed because a photosynthesis model will be used to predict the duckweed growth. I purposely booked a flight so I would land in the late morning, before the heavy afternoon rains kicked in. Duckweed depends on nitrogen, phosphorus and potassium for growth and reproduction, but nitrogen is usually the limiting factor. Duckweed has some desirable properties for water purification. Asexual Reproduction Duckweed reproduces asexually, cloning itself repeatedly. Some 13 months on, we hear from the project leader as to the targets met so far. Duckweed reproduces through vegetative propagation (asexual budding) from an enclosed meristem at the base of the frond. Phytoextraction of zinc, copper, lead, iron, and nickel from landfill leachate by duckweed ( L. minor ) was investigated every 3 days over a period of 2 weeks. 0. The carp didn’t interfere with the wastewater treatment, and were much less expensive than the cost of manually removing duckweed from the lagoon. Reproduction is mainly by division. All these factors are estimated to work in favor of the global duckweed market in the years to come. Duckweed fronds are drought sensitive, but they will survive on a surface of wet mud. To investigate the effects of abscisic acid (ABA) on duckweed biomass and starch accumulation, Spirodela polyrrhiza was cultivated at different ABA concentrations. greater duckweed, is part of the Araceae family (subfamily Lem-noideae) containing 37 or 38 species of duckweed (Landolt, 1986; Les etal., 2002). In late 2017, we reported on an Irish project, Newtrients, involving the capture of essential nutrients from dairy processing wastewater to grow duckweed as a novel feed protein. This growth rate was associated with an up-take rate of NH 4 12. An experiment was performed to test conditions in which duckweed, a small aquatic plant, can reproduce efficiently. Duckweeds can double their mass in between 16 hours to 2 days under optimal nutrient availability, sunlight, and water temperature. It is thought to propagate almost exclu-sively through clonal reproduction … reproduction in Duckweed is vegetative. It is recommended using twenty fish per acre if half the pond area is covered with duckweed. Don’t worry about pollination as means of reproduction. Duckweed can purify and concentrate nutrients from wastewater (sewage effluent). Duckweed can rapidly spread to cover a waterway, resisting all attempts to eliminate it. The duckweed family comprises of 4 genera, Lemna, Spirodela, Wolffia, and Wolfiella, and 34 species. One duckweed can quickly take over or cover the entire surface of a water body within a day. Duckweed plants use asexual reproduction to multiply rapidly on nutrient-rich water. As each frond matures, it begins producing new buds in the meristematic zone near the center of the frond. The biomass of duckweed can be doubled every 48–96 hr depending on various species and culture conditions. Duckweed and watermeal normally do not grow in rivers unless there is a reduced flow of water. Duckweed is considered a noxious invasive in most lakes because of its extreme reproduction and multitudinous growth. This little plant was a ubiquitous part of my childhood since it grew wild in the ponds I played in. Reproduction All plants in the duckweed family reproduce both vegetatively through budding, and by seed. Duckweed (lemnaceae, water lentils) family are the smallest flowering plants and probably the fastest growing plant, capable of doubling its weight in 24 hours.Because of the very high productivity per surface area, duckweed holds great potential for future global villages. Besides looking HORRIBLE, complete surface coverage by weeds can lead to a fish kill. Duckweed reproduces both vegetatively and sexually; vegetatively by asexual budding or division and sexually by flowering, although this is rare. Duckweed is one of the fastest growing plants on earth. In asexual reproduction… You’ll typically find it floating in very big masses in rivers, ponds, and lakes. Correspondingly, how does duckweed reproduce? These characteristics make duckweed a very interesting potential crop. Duckweed growth is optimum at temperatures between 20 and 30 °C, but serious effects will occur at temperatures between 35 and 40 °C. These buds grow into new fronds while still attached to the parent frond. The plant grows and divides asexually, much like a single-celled organism does. Importance of plant: Food for fish and waterfowl and habitat for aquatic invertebrates. The water was treated at least three days prior to adding the duckweed for reproduction in the 5 gal containers. life cycle and reproduction of elodea. Wolffia duckweed measures 1/100 of an inch (0.3 mm) across. Control Controlling duckweed and watermeal is difficult and challenging. We have duckweed … pond. Under ideal conditions one duckweed frond can produce 17,500 “daughters” in just two weeks. Duckweed is spread from pond to pond via waterfowl or other wildlife. Duckweeds can also be “contact pollinated” through the collision of adjacent floating stems that jars pollen loose and on to the receptive stigma. THEORY Early growth in small populations tends to be exponential. showed inhibitory effects on duckweed growth down to 15% concentrations with damaged and necrotic fronds ob-served after 2 to 3 days of growth (Figure 1, Table 1). However, the lifespan of an individual frond in the vegetative phase is relatively short, ranging from Eddie K. H. Ho, Department of Ecology and Evolutionary Biology, University of Toronto, 25 Willcocks Street, Toronto, ON, M5S 3B2 Canada. Duckweed after 10 days was measured as 50 % and 75% respective-ly. Duckweed can reproduce Update - the duckweed did eventually catch up and cover the tank. Each frond can only do this a limited number of times before dying. Through simple transfer of duckweed plants into well water for 10 days, the duckweed starch content increased by 64.9%, resulting in a high annual starch yield of 9.42 × 103 kg ha−1. Duckweed is a tiny floating aquatic plant that can reproduce so rapidly that it can completely cover the surface of small fish hatchery ponds. Dying thalli turn yellow, then brown, fading to translucence, and then they’ll sink. duckweed, but results are highly variable. Watermeal has no roots and looks like floating grass seed about the size of a pin-head. 1. Duckweed mats therefore reduce the ability of C. globularis to maximize reproductive output, potentially leading to a gradual decline of the population. wastewaters were highly toxic. reproduce in lagoons as they require flowing bodies of water for reproduction. Occasionally, three tiny flowers are produced for sexual reproduction. Duckweed farming is a continuous process requiring intensive management for optimum production. With ideal growing conditions, the original plant and its daughter buds can produce as many as 17,500 plants in two weeks. Duckweed (Spirodela polyrrhiza) is widely distributed in the world and has high starch and low lignin contents, which is perhaps an ideal feedstock for bioenergy production. Duckweed can reproduce either sexually or asexually. It uses asexual reproduction to multiply rapidly on nutrient-rich water. Reproduction is Reproduction Duckweeds are very productive and might very well be among the fastest growing plants. As fish food , the quick growth provides an economical and nutritious food source. Common duckweed (Lemna minor) By Walter Fertig. Our established duckweed system for microbial pathogenesis offers many advantages over other eukaryotic systems. You can grow the duckweed at home in bowls of water. High nutrient removal rate from swine wastes and protein biomass production by full -scale duckweed ponds, Biosource Technology This pond plant is a smaller species that floats on the surface of the water. Duckweed. Duckweed after 10 days was measured as 50 % and 75% respective-ly. The cyclic nature of a synchronised duckweed mat (i.e. all the same age) could be over at least 1 month as the life span of fronds from early to late daughters can be 33 or 19d respectively with a 3 fold difference in frond rate production (See Wangermann & Ashby, 1950). Wait while the duckweed floats back over the strainer. Lemnaceae (duckweed) are the world’s smallest, but fastest growing aquatic flowering plants Used for basic research, environmental monitoring and waste ... •Clonal reproduction •48 hours duplication by budding •Limited flowering Spirodela polyrhiza (Landolt, … Related tags: Protein, duckweed, Dairy, Soy. Introduction. Tank Requirements and Water Parameters Scrape all the plants inside the strainer into the weighing boat. Duckweed doesn’t require any special care, and will thrive in everything from low light to high light, and soft water to hard water conditions. It’s actually more difficult to get the duckweed not to grow, than it is to just sit back and allow it to grow on it’s own. A single root (or root-hair) protrudes from each leave. Duckweed grows by asexual reproduction and floats at the surface of the water with tiny roots extending into the water below. Duckweed species: Trial: Results: Reference: Peru: Broilers: Lemna gibba: 0, 10, 15 or 25% dry duckweed in the diet: 25% duckweed resulted in a significant decrease in feed consumption and weight gain but the weight gain of broilers fed 15% duckweed was similar to that of the control diets. An individual leaf may go through 10 divisions over a period of 10 days to several weeks before the original plant senesces. Easily grown, it is a natural food for many animals and keeps … Nutrients like Reproduction is usually by asexual budding. Each “leaf” can form buds several times in its life. How to Identify Duckweed: It is an easily recognizable tiny light green free-floating plant with 1 to 3 leaves 1/16 to 1/8 inch in length. As long as their population is minimal, and controlled, they might be very beneficial to your tank or pond. One week a pond has some growing along the edges, and the next, the whole pond is covered. Adding duckweed to a goldfish tank or pond is a great way to add some enrichment for your fish in the form of a tasty green snack. The plants reproduce at twice the rate of other vascular plants by seed and vegetatively throughout the growing season and spread rapidly within a waterbody, especially in those containing high levels of phosphorus and/or nitrogen. Duckweed is one of the fastest growing plants on earth. The small fruit produced is called a utricle. Duckweed. For plants to survive, they need to reproduce. Occasionally, three tiny flowers are produced for sexual reproduction. 2. Of these, 6 species (under 3 genera) namely, Lemna perpusilla, L. trisulca, Spirodela polyrhiza, S. punctata, Wolffia arrhiza, and W. mircoscopica have so far been reported from Bangladesh. Despite being the smallest angiosperms, flowers are rarely seen due to size and blooming frequency. The duckweeds (genus Lemna) and related genera of the duckweed family (Lemnaceae) are the smallest flowering plants known. duckweed is cultivated is of importance on this research. [3] The fruit produced through this occasional reproduction is a utricle, and a seed is produced in a bag containing the air that facilitates flotation. Duckweed reproduction and spread. Given that c. 80% of angiosperms undergo some form of asexual reproduction (Barrett, 2015; Hartfield, 2016), there is ample opportunity to study the consequences of asexuality. Don’t worry about finding tiny bees. The phosphate removal is more with the presence of Duckweed than original pond water due to the following reason (1) this may be due to phosphate uptake by Duckweed plant and assimilation into plant protein. Duckweed floats at the water’s surface, and spreads rapidly by asexual reproduction via buds on their stems. Duckweed has the smallest flower in the world, but we have never seen it. In cold regions, clusters of fronds sink to the bottom of the body of water in the fall. Duckweed usually has a single round leaf (2-5mm in diameter) and a short root (6-10mm in length). food source for wildlife, including fish and birds (hence the name “duckweed”). It is predicted that a lower light intensity will lower the rate of growth in duckweed. Under suitable circumstances, duckweed has an overwhelm-ing reproduction capability. Note the weight of the plants. So, you can imagine the growth rate of this aquatic plant. Little Duckweed (Lemna obscura) is on the "watch list." 3. Along with black soldier fly larvae and growing our own grains, duckweed is at the top of our list for this year’s chicken feed experiments. The flower of the duckweed genus Wolffia is the smallest known, measuring merely 0.3 mm long. Distributed by wind and on the bodies of birds, and aquatic animals. This very efficient reproductive process results in a very rapid growth cycle. Similar to animals, … Gently raise the strainer and allow the water to drain off. Since duckweed is so quick and easy to grow, students can learn how to study concepts of exponential growth, heavy metal toxicity, photosynthesis, and asexual reproduction. Wolffia duckweed is green or yellow vegetative tissue–somewhat akin to a frond or very tiny leaf. This very efficient reproductive process results in a very rapid growth cycle. Maximum growth rate of duckweed (7.03 g m-2 day-1) was also observed for synthetic leachate in comparison to the growth rate of 4.87 g m-2 day-1 at dumpsite leachate. While in your water garden, this plant can provide shade to life below if desired. Duckweed is very prolific, and given enough nitrogen and phosphorus nutrients, it is possible for a new duckweed plant to be produced every 24 hours. Below 17 °C some duckweeds show a decreasing rate of growth. Vegetative reproduction: Life cycle: Perennial; Comments: State status Status and Natural Heritage Inventory documented occurrences in Wisconsin. This BiologyWise article is an attempt to understand asexual reproduction in plants, and how it differentiates from sexual reproduction in plants. Results of this study proved that L. minor significantly reduced the concentration of heavy metals in landfill leachate. But once there is an overgrowth of duckweed, it becomes dangerous to the ecosystem of the water body because of their sporadic rate of reproduction. Phytoextraction of zinc, copper, lead, iron, and nickel from landfill leachate by duckweed ( L. minor ) was investigated every 3 days over a period of 2 weeks. There are non-chemical and chemical Vegetative reproduction: Life cycle: Perennial; Comments: State status Status and Natural Heritage Inventory documented occurrences in Wisconsin. It is important to note that duckweed, because of its high reproductive rate, adapts quickly to changes in its environment, including environ­ mental toxins. New fronds grow from buds on parent fronds (Molstad, 2016). In the process, it absorbs the dissolved nutrients and purifies the water. Duckweed and Watermeal reproduce by budding on the margin or base of the frond. Is duckweed harmful? However, the lifespan of an individual frond in the vegetative phase is relatively short, ranging from They are classified as angiosperms since three extremely small flowers can be produced periodically, though which sexual reproduction occurs. The plant mass can double in size every two or three days in optimum conditions over summer. It may take several years to adequately control the duckweed. One proposal to limit the growth of this invasive plant is the use colored panels to shield the ponds, inhibit photosynthesis, and kill this pest. The invention relates to a preparation method of duckweed protein powder for fermentation. Photography by Ryan Gutierrez and Philomena Chu, Laboratory of Eric Lam, Department of Plant Biology and Pathology, Rutgers, The … In this practical, you can either collect duckweed from the surface of a pond, or from an aquarium in the lab. Under ideal conditions, Duckweed treats waste by breaking it down and converting it into two components: biomass (duckweed leaves and roots) and treated water. They are especially important as a food source for waterfowl. In the process, they absorb the dissolved nutrients and purify the water. duckweed plant produces a daughter bud about once a day. tribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is prop- erly cited. Bioconcentration factor and removal efficiency were also calculated. Duckweed and watermeal are floating weeds that reproduce VERY FAST! Reproduction Duckweeds are very productive and might very well be among the fastest growing plants. The duckweed grew well in 10 to 1.2% ADSW with the highest growth rate, 5.4 g dry weight (dw)/m2-day, observed in 10% ADSW. Duckweed is commonly spread by migratory birds flying between ponds with the tiny plants clinging to their feathers. Duckweed is commonly spread by migratory birds flying between ponds with the tiny plants clinging to their feathers. Duckweed is an incredible radiation-fighting astronaut food and by changing how it is grown, we made it better, Theconversation.com Duckweed world, Phys.org Algae & duckweed, costs and benefits, Brandywine.org. Duckweed Frond Counts-Class Averages Day 1 Day 3 Day 5 Day 8 Control 100% 10% 1% 0.10% 0.01% 0.001% Question #4 TC50 TC50 The Toxic Concentration that kills 50% of Duckweed OR The Toxic Concentration that causes Duckweed to grow ½ as well as those in the control group 1. This type of reproduction is one method of vegetative propagation, where there are no seeds … Water Lettuce (Pistia) by Jim Mullhaupt / CC BY-NC-ND 2.0. Duckweed Market Introduction: Duckweed is a species of plant with small round leaves floating on the surface of the water. reproduction of duckweed. Growing duckweed has numerous benefits whether used as a feed for livestock, biofuel for ethanol production or even as a food for human nutrition. The fruit produced through this occasional reproduction is a utricle, and a seed is produced in a bag containing air that facilitates flotation. They reproduce by budding, and in some cases, can produce a new plant every 24 hours. Common duckweed (Lemna minor) is a rapidly spreading aquatic plant that deprives ponds of oxygen and leads to the death of fish and beneficial algae in still waters.It is important to get rid of duckweed for the health of your pond and existing aquatic life. (2) Adsorption on plant leaves, (3) Chemical precipita- As duckweed usually proliferates through asexual reproduction, the classic hybrid breeding method is difficult to be applied on duckweed. Given their clonal, exponentially fast reproduction, a key question is whether genome structure is conserved across the species in the absence of meiotic recombination. Duckweed reproduces asexually, cloning itself repeatedly. Asexual reproduction is a process in which gametes do not fuse together. Closer observation reveals that the scum is actually made up of tiny, individual plants. An estimated 17,500 plants can be produced by 1 duckweed parent, in 2 weeks of summer. These buds grow into new fronds while still attached to … In August, they can even cover the entire surface. An estimated 17,500 plants can be produced by 1 duckweed … At this point, they have likely already begun producing fronds of their own. Lemna is a genus of free-floating aquatic plants referred to by the common name "duckweeds." Duckweed mortality and reproduction tests showed that the effects were nearly total. The fruits contain several ribbed seeds which are capable of going into dormancy and will germinate under favorable conditions. In most cases, duckweed reproduces by means of asexual reproduction, called budding. Reproduction is generally vegetative and its growth rate is tremendous, A thumb-sized planting will cover 1.2 acres in 55 days if uninhibited. Wolffia Arrhiza Watermeal Duckweed Starter Culture Packet containing 1x 15ml plastic tube of live aquatic plants! Some source of nutrients being supplied from chicken dung, cattle dung, pig waste or any other organic matter in slurry form. Duckweed plants use asexual reproduction to multiply rapidly on nutrient-rich water. In the spring, the plants float to the surface and begin reproducing. In the process, they absorb the dissolved nutrients and purify the water. the nutrient availability. Lemna Duckweed is, as noted earlier, one of the really good weeds. food source for wildlife, including fish and birds (hence the name “duckweed”). life cycle and reproduction of elodea. This makes it either a formidable enemy or a fantastic ally. noun. Dealing with Excessive Lemna Duckweed and How to Control this Lake Weed. Common duckweed can be used to remove excess nutrients or toxic metals from water bodies (called phytoremediation) because it is an efficient bio-accumulator, is fast-growing and hardy, and is easily removed from the water after use. It simply grows new leaves (called thalli) until a plant is large enough to separate into a new individual. Duckweed has some desirable properties for water purification. The three available genera of duckweeds can be easily identified by their distinctive general appearances. asexual reproduction: frond multiplication by budding of daughter fronds (without flowering and fertilization of the ovary by pollen) sexual reproduction: complete flower or male/female flower, rarely observed. It absorbs harmful nitrates and other chemicals from the water, thereby improving water quality and because of its spreading canopy, reduces the light that fuels algae . Duckweed usually has a single round leaf (2-5mm in diameter) and a short root (6-10mm in length). Analogously, plants are useful for modeling bacterial pathogenesis, in some cases revealing broadly conserved infection mechanisms. How fast does duckweed reproduce? duck +‎ weed. IntroductionLemnaceae, or duckweed as it is commonly called, is a well-known organism that is ideal for biological experiments due to its easy maintenance, rapid reproduction rate and abundance (Kuhn, D., 1969). Duckweed is easier to harvest than algae or other aquatic plants. As winter approaches, the duckweed sinks to the bottom and, in the spring, some of them rise back to the surface to start a new population. Duckweed may occasionally flower and produce seed, but very rarely ... Reproduction starts in summer, allowing the colonization of large surfaces. Duckweed in fact does not need phosphate to reproduce and live. The flower of the duckweed genus Wolffia is the smallest known, just 0.3 mm long. duckweed. The simple body is leaf-like, generally flat on top and convex below, lacks stems or leaves, is oval to tear-dropped in shape, and has one unbranched root that lacks vascular (conducting) tissue.The upper surface of the plant is covered with waxy compounds so as to shed water. Dying thalli turn yellow, then brown, fading to translucence, and then they’ll sink. Duckweed is an aquatic plant that is commonly found in lakes, forming what seems to be a green blanket over the water. Since free-floating plants reproduce so quickly, mechanical methods are only temporary solutions. e.g., plants are small and grow fast, thus multiple treatments can be performed simultaneously in a contained environment with low cost. Duckweed does not like moving water or windswept water even if the nutrients are high. Brush all the duckweed off the outside. Duckweed is also very sensitive to herbicides, mak­ ing it more appropriate than other species in assaying for herbicides (Wang unpublished). Their fibrous roots float as well, taking up nutrients directly from the water. Reproduction is usually by asexual budding. However, with Increased run-off and sewage many still-moving lakes and ponds contain high nitrogen levels needed for duckweed growth. Take a closer look. ... minute flowering plants that float on ponds and sluggish streams and reproduce by a kind of budding: so called because eaten by ducks. Ducks, geese and other birds easily transport specimens from one body of water to the next. ABSTRACT . It provides food for fish and wildlife and can reproduce every three days at the optimal temperature and nutrient levels. The plant thrives in the protected, still water of ponds, lakes, and lagoons. In asexual reproduction… Duckweed is a small aquatic plant that is able to grow rapidly, making it the ideal specimen for our experiment. duckweed. Primarily, reproduction is by cloning, each thallus can produce about ten daughters; (clones), before death. These flowers have two stamens and a pistil. It is about the size of a speck of cornmeal. 4. Population genomics of the facultatively asexual duckweed Spirodela polyrhiza. Wait while the duckweed floats back over the strainer. Will the duckweed grow well in different types of water? How fast does duckweed reproduce? Fresh duckweed is between 90 and 95 percent water; this is not surprising since it is an aquatic mass with a low enough density to float. A single lesser duckweed plant can reproduce itself about every 3 days under ideal conditions in nutrient-rich waters. Can you find duckweed from a local pond or wetland? Alternative animal host models of bacterial infection have been developed which reproduce some of the disease conditions observed in higher animals. Reproduction is generally vegetative and its growth rate is tremendous, A thumb-sized planting will cover 1.2 acres in 55 days if uninhibited. I wasn't pleased with the state in which it arrived, but it eventually worked out. Wastewaters from source C, … It can cover 1 acre in just 45 days if left unrestrained. One proposal to limit the growth of this invasive plant is to use colored panels to shield the ponds, inhibit photosynthesis, and kill this pest. Duckweed can grow thick! From this occasional reproduction is produced a seed in an air bag that floats. Look at Control Day 1 – 20 fronds Day 8- ___ fronds 2. Plants such as corn, sugar cane and elephant grass have been studied for their use as a bio fuel. Mark the base of a shallow However, temporary control may be all you need to enjoy a fishing trip or a swimming party. One duckweed can quickly take over or cover the entire surface of a water body within a day. Three duckweed plants were placed in each of four culture dishes at room temperature with the following solutions: 1) distilled water, 2) pond water, 3) an N-P-K fertilizer solution, and 4) a nitrate-enriched solution. Duckweeds bud. Generally, the reproduction rate of duckweed and watermeal are astounding given the right nutrient load in the water. The flower of the duckweed genus Wolffia is the smallest known, just 0.3 mm long.
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