Editing Xylem (section)

== History ==

In his book ''De plantis libri XVI'' (On Plants, in 16 books) (1583), the Italian physician and botanist [[Andrea Cesalpino]] proposed that plants draw water from soil not by magnetism (''ut magnes ferrum trahit'', as magnetic iron attracts) nor by suction (''vacuum''), but by absorption, as occurs in the case of linen, sponges, or powders.<ref>See:
* {{cite book |last1=Cesalpino |first1=Andrea |title=De Plantis libri XVI |trans-title=On Plants, in 16 books |date=1583 |publisher=Giorgio Marescotti |location=Florence, Italy |page=[https://archive.org/details/deplantislibrixv00cesa/page/4 4] |language=la |url=https://archive.org/details/deplantislibrixv00cesa }}  From p. 4: ''"An quædam sicca secundum naturam humorem trahunt? ut lintea, spongiæ, pulveres: ... "'' (Or [as] dry things attract [i.e., absorb] according to the liquid's nature? [such] as linen, sponges, powders: ... )
* {{cite book |last1=Bellorini |first1=Cristina |title=The World of Plants in Renaissance Tuscany: Medicine and Botany |date=2016 |publisher=Routledge |location=Abingdon-on-Thames, England |page=72 |url=https://books.google.com/books?id=ZtFRDQAAQBAJ&pg=PT72|isbn=9781317011491 }}
* {{cite book |last1=Kramer |first1=Paul J. |last2=Boyer |first2=John S. |title=Water Relations of Plants and Soils |date=1995 |publisher=Elsevier Science |location=London, England |page=2 |url=https://books.google.com/books?id=H6aHAwAAQBAJ&pg=PA2|isbn=9780080924113 }}</ref> The Italian biologist [[Marcello Malpighi]] was the first person to describe and illustrate xylem vessels, which he did in his book ''Anatome plantarum'' ... (1675).<ref>See:
* {{cite book |last1=Malpighi |first1=Marcello |title=Anatome Plantarum ... |date=1675 |publisher=Royal Society of London |location=London, England, UK |page=8 |url=https://books.google.com/books?id=DBp8TQ_B0oAC&pg=PA8 |language=la }}
* {{cite journal |last1=Jansen |first1=Steven |last2=Schenk |first2=H. Jochen |title=On the ascent of sap in the presence of bubbles |journal=American Journal of Botany |date=2015 |volume=102 |issue=10 |pages=1561–1563 |doi=10.3732/ajb.1500305 |pmid=26400778 |doi-access=free }}
* Lazenby, Elizabeth Mary (1995) "The ''Historia Plantarum Generalis'' of John Ray:  Book I – a translation and commentary.", doctoral thesis, University of Newcastle upon Tyne, England, UK, vol. 1, p. 160.  Available at:  [https://theses.ncl.ac.uk/dspace/bitstream/10443/327/1/Lazenby95v.1.pdf University of Newcastle upon Tyne, UK.] {{Webarchive|url=https://web.archive.org/web/20180814103423/https://theses.ncl.ac.uk/dspace/bitstream/10443/327/1/Lazenby95v.1.pdf |date=2018-08-14 }}</ref><ref group=note>Malpighi first described xylem vessels and named tracheid cells.  From p. 8 of (Malpighi, 1675): ''" ... haec tubulosa sunt & subrotunda, identidem tamen angustantur, & perpetuo patent, nullumque, ut observare potui, effundunt humorem: Argentea lamina L, in spiram contorta, componuntur, ut facile laceratione, (velut in bombycinis tracheis expertus sum,) in hanc oblongam & continuatam fasciam resolvantur. Lamina haec, si ulterius microscopio lustretur, particulis squamatim componitur; quod etiam in tracheis insectorum deprehenditur. Spiralibus hisce vasculis, seu ut verius loquar, tracheis, ligneae fibrae M adstant, quae secundum longitudinem productae, ad majorem firmitudinem & robur, transversalium utriculorum ordines N superequitant, ita ut fiat veluti storea."'' ( ... these [vessels] are tubular and somewhat round, yet often become narrow, and they are always open, and none, as [far as] I could perceive, exude a liquid: they are composed of silvery sheets ''L'', twisted into a helix, although they can easily be unbound, by tearing, into this somewhat long and connected strip (just as I have done in silkworm treacheas).  This sheet, if it be examined further with a microscope, is composed of scale-like particles; which likewise is observed in the tracheas of insects.  On these helical vessels, or as I will more rightly say, "tracheas", there stand woody filaments ''M'', which being extended in length straddle – for greater strength and hardness – lines of transverse cells ''N'', so that it is constructed like a mat.)</ref> Although Malpighi believed that xylem contained only air, the British physician and botanist [[Nehemiah Grew]], who was Malpighi's contemporary, believed that sap ascended both through the bark and through the xylem.<ref>{{cite book |last1=Grew |first1=Nehemiah |title=The Anatomy of Plants ... |date=1682 |publisher=W. Rawlins |location=London, England |pages=124–125 |url=https://archive.org/stream/mobot31753000008869#page/123/}} From pp. 124–125: "For the great part of the year, it [i.e., the sap] riseth in the ''Barque'' [i.e., bark], sc. in the inner ''Margin'' adjacent to the ''Wood'', and in the ''spring'', in or through the ''Wood'' it self, and there only."</ref> However, according to Grew, [[capillary action]] in the xylem would raise the sap by only a few inches; to raise the sap to the top of a tree, Grew proposed that the parenchymal cells become turgid and thereby not only squeeze the sap in the tracheids but force some sap from the parenchyma into the tracheids.<ref>See:
* (Grew, 1682), p. 126.  Grew recognized the limits of capillary action (from p. 126): " ... small ''Glass-Pipes'' [i.e., capillary tubes] immersed in Water, will give it [i.e., the water] an ascent for some inches; yet there is a certain ''period'', according to the ''bore'' of the ''Pipe'', beyond which it will not rise."  Grew proposed the following mechanism for the ascent of sap in plants (from p. 126): "But the ''Bladders'' [i.e., parenchymal cells]  DP, which surround it [i.e., the column of tracheids], being swelled up and turgid with ''Sap'', do hereby press upon it; and so not only a little contract its bore, but also transfuse or strain some ''Portion'' of their ''Sap'' thereinto: by both which means, the ''Sap'' will be forced to rise higher therein."
* {{cite book |last1=Arber |first1=Agnes |editor1-last=Oliver |editor1-first=Francis Wall |title=Makers of British Botany: A Collection of Biographies by Living Botanists |date=1913 |publisher=Cambridge University Press |location=Cambridge, England |page=58 |chapter-url=https://www.biodiversitylibrary.org/item/16228#page/86/mode/1up |chapter=Nehemiah Grew 1641–1712}}</ref> In 1727, English clergyman and botanist [[Stephen Hales]] showed that transpiration by a plant's leaves causes water to move through its xylem.<ref>{{cite book |last1=Hales |first1=Stephen |title=Vegetable Staticks: Or, an account of some statical experiments on the sap in vegetables: ... |date=1727 |publisher=W. & J. Innys and T. Woodward |location=London, England |page=[https://archive.org/details/vegetablestatick00hale/page/100 100] |url=https://archive.org/details/vegetablestatick00hale/page/100 |isbn=9780356030128 }}</ref><ref group=note>Hales explained that although capillary action might help raise water within the xylem, transpiration caused water to actually move through the xylem.
From (Hales, 1727), p. 100: "And by the same [capillary] principle it is, that we see in the preceding Experiments plants imbibe moisture so vigorously up their fine capillary vessels; which moisture, as it is carried off in perspiration [i.e., transpiration], (by the action of warmth), thereby gives the sap vessels liberty to be almost continually attracting fresh supplies, which they could
not do, if they were fully saturate with moisture: For without perspiration the sap must necessarily stagnate, not withstanding the sap vessels are so curiously adapted by their exceeding fineness, to raise the sap to great heights, in reciprocal proportion to their very minute diameters."</ref> By 1891, the Polish-German botanist [[Eduard Strasburger]] had shown that the transport of water in plants did not require the xylem cells to be alive.<ref>See:
* {{cite book |last1=Strasburger |first1=Eduard |title=Histologische Beiträge |trans-title=Histological Contributions |date=1891 |publisher=Gustav Fischer |location=Jena, Germany |language=de |volume=3: ''Ueber den Bau und die Verrichtungen der Leitungsbahnen in den Pflanzen'' [On the structure and the function of vascular bundles in plants] |pages=607–625: ''Aufsteigen giftiger Flüssigkeiten bis zu bedeutender Höhe in der Pflanze'' [Ascent of poisonous liquids to considerable heights in plants], pp. 645–671: ''Die Leitungsfähigkeit getödteter Pflanzentheile'' [The ability of the killed parts of plants to conduct [water]]|url=https://books.google.com/books?id=rjMaAAAAYAAJ&pg=PA607 }}
* (Jansen & Schenck, 2015), p. 1561.</ref>