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40-429: Sap is distinct from latex , resin , or cell sap ; it is a separate substance, separately produced, and with different components and functions. Insect honeydew is called sap, particularly when it falls from trees, but is only the remains of eaten sap and other plant parts. Saps may be broadly divided into two types: xylem sap and phloem sap. Xylem sap (pronounced / ˈ z aɪ l ə m / ) consists primarily of

80-424: A "second skin" effect. Synthetic latices are used in coatings (e.g., latex paint) and glues because they solidify by coalescence of the polymer particles as the water evaporates. These synthetic latices therefore can form films without releasing potentially toxic organic solvents in the environment. Other uses include cement additives and to conceal information on scratchcards . Latex, usually styrene -based,

120-439: A better protection to the plant from enemies than all the thorns, prickles, or hairs that could be provided. In this plant, so copious and so distasteful has the sap become that it serves a most important purpose in its economy. Evidence showing this defense function include the finding that slugs will eat leaves drained of their latex but not intact ones, that many insects sever the veins carrying latex before they feed, and that

160-406: A branching system extending throughout the plant. In many euphorbs , the entire structure is made from a single cell – this type of system is known as a non-articulated laticifer , to distinguish it from the multi-cellular structures discussed above. In the mature plant, the entire laticiferous system is descended from a single cell or group of cells present in the embryo . The laticiferous system

200-409: A higher essential/non-essential amino acid ratio and lower osmotic pressure," or by feeding on the biomass of insects that have grown on more direct ingestion of phloem sap. Maple syrup is made from reduced sugar maple xylem sap. The sap often is harvested from the sugar maple, Acer saccharum . In some countries (e.g., Lithuania , Latvia , Estonia , Finland , Belarus , Russia ) harvesting

240-405: A latex allergy. Latex-fruit syndrome Many people with latex allergy also experience allergic reactions to certain fruits. This association has led to research regarding latex-fruit syndrome (LFS). This is a phenomenon characterized by cross-reactivity between natural latex rubber allergens and certain fruit allergens, leading to allergic reactions in sensitized individuals. It was described for

280-531: A lower-allergen substitute. Additionally, chemical processes may be employed to reduce the amount of antigenic protein in Hevea latex, yielding alternative materials such as Vytex Natural Rubber Latex which provide significantly reduced exposure to latex allergens. About half of people with spina bifida are also allergic to natural latex rubber. People who have had multiple surgeries and who have had prolonged exposure to natural latex are also more susceptible to

320-505: A mechanism for phloem sap transport, although other hypotheses have been proposed. Phloem sap is thought to play a role in sending informational signals throughout vascular plants. According to Annual Review of Plant Biology , Loading and unloading patterns are largely determined by the conductivity and number of plasmodesmata and the position-dependent function of solute -specific, plasma membrane transport proteins . Recent evidence indicates that mobile proteins and RNA are part of

360-590: A mutually symbiotic arrangement with ants are called Myrmecophiles . In Madagascar, some gecko species in the genera Phelsuma and Lygodactylus are known to approach flatid plant-hoppers on tree-trunks from below and induce them to excrete honeydew by head nodding behaviour. The plant-hopper then raises its abdomen and excretes a drop of honeydew almost right onto the snout of the gecko. Honeydew can cause sooty mold on many ornamental plants . It also contaminates vehicles parked beneath trees, and can then be difficult to remove from glass and bodywork. Honeydew

400-568: A symbiotic organism is present. Honeydew-producing insects, like cicadas , pierce phloem ducts to access the sugar rich sap; the excess fluid released by cicadas as honeydew is called "cicada rain". The sap continues to bleed after the insects have moved on, leaving a white sugar crust called manna. Ants may collect, or "milk", honeydew directly from aphids and other honeydew producers, which benefit from their presence due to their driving away predators such as lady beetles or parasitic wasps—see Crematogaster peringueyi . Animals and plants in

440-566: A watery solution of hormones , mineral elements and other nutrients . Transport of sap in xylem is characterized by movement from the roots toward the leaves . Over the past century, there has been some controversy regarding the mechanism of xylem sap transport; today, most plant scientists agree that the cohesion-tension theory best explains this process, but multiforce theories that hypothesize several alternative mechanisms have been suggested, including longitudinal cellular and xylem osmotic pressure gradients , axial potential gradients in

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480-489: Is actively moved to the area of injury; in the case of Cryptostegia grandiflora , latex more than 70 cm from the site of injury is mobilized. The large hydrostatic pressure in this vine enables an extremely high flow rate of latex. In a 1935 report the botanist Catherine M. Bangham observed that "piercing the fruit stalk of Cryptostegia grandiflora produced a jet of latex over a meter long, and maintained [this jet] for several seconds." The clotting property of latex

520-464: Is also secreted by certain fungi, particularly ergot . Honeydew is collected by certain species of birds, mosquitoes, wasps , stingless bees and honey bees , which process it into a dark, strong honey ( honeydew honey ). This is highly prized in parts of Europe and Asia for its reputed medicinal value. Parachartergus fraternus , a eusocial wasp species, collects honeydew to feed to their growing larvae. Recent research has also documented

560-475: Is also slow. Honeydew (secretion) Honeydew is a sugar -rich sticky liquid , secreted by aphids , some scale insects , and many other true bugs and some other insects as they feed on plant sap . When their mouthpart penetrates the phloem , the sugary, high-pressure liquid is forced out of the anus of the insects, allowing them to rapidly process the large volume of sap required to extract essential nutrients present at low concentrations. Honeydew

600-469: Is also used in immunoassays . Some people only experience a mild allergy when exposed to latex, with symptoms such as eczema , contact dermatitis , or developing a rash . Others have a serious latex allergy , and exposure to latex products such as latex gloves can cause anaphylactic shock . Guayule latex has only 2% of the levels of protein found in Hevea latices, and it is being researched as

640-432: Is also used to refer to natural latex rubber , particularly non- vulcanized rubber. Such is the case in products like latex gloves , latex condoms , latex clothing , and balloons . Latex : Colloidal dispersion of polymer particles in a liquid. Synthetic latex : Latex obtained as a product of an emulsion , mini-emulsion, micro-emulsion, or dispersion polymerization . The cells ( laticifers ) in which latex

680-434: Is an emulsion (stable dispersion) of polymer microparticles in water. Latices are found in nature , but synthetic latices are common as well. In nature, latex is found as a milky fluid , which is present in 10% of all flowering plants (angiosperms). It is a complex emulsion that coagulates on exposure to air, consisting of proteins , alkaloids , starches , sugars , oils , tannins , resins , and gums . It

720-631: Is consumed as the dominant or sole diet by a very restricted range of animals". This apparent paradox is explained by the fact that phloem sap is physiologically extreme in terms of animal digestion, and it is hypothesized that few animals take direct advantage of this because they lack two adaptations that are necessary to enable direct use by animals. These include the existence of a very high ratio of non-essential / essential amino acids in phloem sap for which these adapted Hemiptera insects contain symbiotic microorganisms which can then provide them with essential amino acids; and also insect "tolerance of

760-474: Is found in the poppy family and in the rubber trees ( Para rubber tree , members of the family Euphorbiaceae , members of the mulberry and fig family , such as the Panama rubber tree Castilla elastica ), and members of the family Asteraceae . For instance, Parthenium argentatum the guayule plant, is in the tribe Heliantheae ; other latex-bearing Asteraceae with articulated laticifers include members of

800-430: Is found make up the laticiferous system, which can form in two very different ways. In many plants, the laticiferous system is formed from rows of cells laid down in the meristem of the stem or root . The cell walls between these cells are dissolved so that continuous tubes, called latex vessels, are formed. Since these vessels are made of many cells, they are known as articulated laticifers . This method of formation

840-455: Is functional in this defense since it limits wastage and its stickiness traps insects and their mouthparts. While there exist other explanations for the existence of latex including storage and movement of plant nutrients, waste, and maintenance of water balance that "[e]ssentially none of these functions remain credible and none have any empirical support". The latex of many species can be processed to produce many materials. Natural rubber

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880-420: Is particularly common as a secretion in hemipteran insects and is often the basis for trophobiosis . Some caterpillars of Lycaenidae butterflies and some moths also produce honeydew. In addition to various sugars, honeydew contains small amounts of amino acids , other organic compounds, and inorganic salts with its precise makeup affected by factors such as insect species, host plant species, and whether

920-595: Is present in all parts of the mature plant, including roots, stems, leaves , and sometimes the fruits . It is particularly noticeable in the cortical tissues. Latex is usually exuded as a white liquid, but is some cases it can be clear, yellow or red, as in Cannabaceae . Latex is produced by 20,000 flowering plant species from over 40 families . These include both dicots and monocots . Latex has been found in 14 percent of tropical plant species, as well as six percent of temperate plant species. Several members of

960-496: Is the most important product obtained from latex; more than 12,000 plant species yield latex containing rubber, though in the vast majority of those species the rubber is not suitable for commercial use. This latex is used to make many other products including mattresses , gloves , swim caps , condoms , catheters and balloons . Dried latex from the opium poppy is called opium , the source of several useful analgesic alkaloids such as codeine , thebaine , and morphine ,

1000-512: Is usually exuded after tissue injury. In most plants, latex is white, but some have yellow, orange, or scarlet latex. Since the 17th century, latex has been used as a term for the fluid substance in plants, deriving from the Latin word for "liquid". It serves mainly as defense against herbivorous insects . Latex is not to be confused with plant sap ; it is a distinct substance, separately produced, and with different functions. The word latex

1040-483: The Cichorieae , a clade whose members produce latex, some of them in commercially interesting amounts. This includes Taraxacum kok-saghyz , a species cultivated for latex production. In the milkweed and spurge families, on the other hand, the laticiferous system is formed quite differently. Early in the development of the seedling, latex cells differentiate, and as the plant grows these latex cells grow into

1080-641: The early spring sap of birch trees (so called " birch juice ") for human consumption is common practice; the sap can be used fresh or fermented and contains xylitol . Certain palm tree sap can be used to make palm syrup . In the Canary Islands they use the Canary Island date palm while in Chile they use the Chilean wine palm to make their syrup called miel de palma . Latex Latex

1120-710: The first time by Blanco et al. in 1994. In a 2024 comprehensive review by Gromek et al., the last 30 years of research on LFS were summarized, focusing on its prevalence, common cross-reactions, and clinical manifestations. The review found that the prevalence of LFS in latex-allergic patients varies widely, ranging from 4% to 88%, depending on diagnostic methods, geographical regions, and study populations. The most commonly implicated fruits in LFS include banana, avocado, kiwifruit, and papaya. Clinical manifestations are predominantly systemic, with 73% of hypersensitivity symptoms being systemic and 27% localized. Gromek et al. also highlighted

1160-447: The fungal kingdom also produce latex upon injury, such as Lactarius deliciosus and other milk-caps . This suggests it is the product of convergent evolution and has been selected for on many separate occasions. Latex functions to protect the plant from herbivores. The idea was first proposed in 1887 by Joseph F. James, who noted that latex of milkweed carries with it at the same time such disagreeable properties that it becomes

1200-486: The honeydew nectar and manna tends to increase in spring and autumn. Eucalyptus can produce even more manna than honeydew nectar. The sugar glider eats both, licking the nectar from branches. Other species attracted to the nectar include the feathertail glider , brush-tailed phascogale , and brown antechinus . Most trees are not able to produce sap if the phloem duct becomes damaged by mechanical processes. The acorn weevil ( Curculio glandium ) habitually bores into

1240-521: The infant god Zeus on the island of Crete (as in the Hymn to Zeus by Callimachus ). Honey-dew is referenced in the last lines of Samuel Coleridge 's poem Kubla Khan , perhaps because of its mythological connotations: And all who heard should see them there, And all should cry, Beware! Beware! His flashing eyes, his floating hair! Weave a circle round him thrice, And close your eyes with holy dread, For he on honey-dew hath fed, And drunk

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1280-411: The latex of Asclepias humistrata (sandhill milkweed ) kills by trapping 30% of newly hatched monarch butterfly caterpillars. Other evidence is that latex contains 50–1000× higher concentrations of defense substances than other plant tissues. These toxins include ones that are also toxic to the plant and consist of a diverse range of chemicals that are either poisonous or " antinutritive. " Latex

1320-441: The latter two of which can then further be used in the synthesis and manufacture of other (typically stronger) opioids for medicinal use, and of heroin for the illegal drug trade . The opium poppy is also the source of medically useful non-analgesic alkaloids, such as papaverine and noscapine . Latex is used in many types of clothing . Worn on the body (or applied directly by painting), it tends to be skin-tight , producing

1360-687: The milk of Paradise. Ommatissus lybicus is attracted to certain cultivars of the date palm tree . The honeydew producing insects preferred the Medjhool variety to the Deglet Noor in Israel , where they have been observed in the Arava Valley . Very dense insect populations may have some adverse effects. Different methods of controlling the insects, including natural and chemical, have been studied. In eucalypt forests, production of both

1400-418: The need for standardized diagnostic criteria and severity grading systems to improve the accuracy of LFS diagnosis and treatment. Several species of the microbe genera Actinomycetes , Streptomyces , Nocardia , Micromonospora , and Actinoplanes are capable of consuming rubber latex. However, the rate of biodegradation is slow, and the growth of bacteria utilizing rubber as a sole carbon source

1440-445: The plant's long-distance communication signaling system. Evidence also exists for the directed transport and sorting of macromolecules as they pass through plasmodesmata. Many insects of the order Hemiptera (the half-wings), feed directly on phloem sap, and make it the primary component of their diet. Phloem sap is "nutrient-rich compared with many other plant products and generally lacking in toxins and feeding deterrents, [yet] it

1480-661: The use of honeydew by over 40 species of wild, native, mostly solitary bees in California. In Norse mythology , dew falls from the ash tree Yggdrasil to the earth, and according to the Prose Edda book Gylfaginning , "this is what people call honeydew and from it bees feed." In Greek mythology , méli , or "honey", drips from the Manna–ash ( Fraxinus ornus ), with which the Meliae , or "ash tree nymphs ", nursed

1520-430: The very high sugar content and osmotic pressure of phloem sap is promoted by their possession in the gut of sucrase - transglucosidase activity, which transforms excess ingested sugar into long-chain oligosaccharides ." A much larger set of animals do however consume phloem sap by proxy, either "through feeding on the honeydew of phloem-feeding hemipterans. Honeydew is physiologically less extreme than phloem sap, with

1560-763: The vessels, and gel- and gas-bubble-supported interfacial gradients. Xylem sap transport can be disrupted by cavitation —an "abrupt phase change [of water] from liquid to vapor"—resulting in air-filled xylem conduits. In addition to being a fundamental physical limit on tree height, two environmental stresses can disrupt xylem transport by cavitation: increasingly negative xylem pressures associated with water stress , and freeze-thaw cycles in temperate climates. Phloem sap (pronounced / ˈ f l oʊ ɛ m / ) consists primarily of sugars , hormones, and mineral elements dissolved in water. It flows from where carbohydrates are produced or stored (sugar source) to where they are used (sugar sinks). The pressure flow hypothesis proposes

1600-551: The young acorns of oak trees . This injury can cause the tree to release a sweet honeydew, thought to attract wasps that can parasitize the weevil within its acorns. Honey bees sometimes collect this substance, in addition to honeydew from aphids feeding in oak forests, and use it to produce oak honey , an unusual varietal sold by specialist beekeepers . Two scale insects in the Sinai , Trabutina mannipara and Najacoccus serpentinus , feed on Tamarisk trees . They secrete

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