شکل ظاهری برگ‌ها بسیار متنوع است. آن‌ها به شکل‌های دایره ٬بیضی ٬نیزه٬پر٬پنجه٬قلب و بسیاری شکل‌های دیگر هستند، اما در مجموع می‌توان آن‌ها را به سه گروه تقسیم کرد: برگ‌های پهن، برگ‌های باریک و برگ‌های سوزنی. غیر از این سه گروه برخی گیاهان مانند سرو کوهی برگ‌های پولک مانند دارند. شگل برگ گیاهان یکی از راه‌های مهم شناسایی نوع گیاه است. طول بیشتر برگ‌ها میان ۵/۲ تا ۳۰ سانتی‌متر است. اما برگ برخی از گیاهان بسیار بزرگ است، برای مثال طول بعضی از برگ‌های نوعی نخل آفریقایی به ۲۰ متر هم می‌رسد یا قطر نوعی از برگ‌های شناور که در مرداب‌های آمریکای جنوبی می‌رویند، به ۸/۱ متر می‌رسد، همچنین در مرداب انزلی، قطر برگ‌های دایره‌ای نیلوفر آبی گاه به بیش از ۵۰ سانتیمتر نیز می‌رسند. تعداد برگ‌ها در گیاهان گوناگون نیز متفاوت است. گیاهانی مانند گندم و ذرت دارای تنها چند برگ هستند. درختان کهنسال نارون صدها هزار برگ دارند. بعضی از گیاهان تنها یک برگ دارند. برگ‌ها یا ساده هستند یا مرکب. برگی که یک پهنک داشته باشد برگ مرکب است و پهنک‌های برگ مرکب را برگچه می‌نامند. برگچه‌های برگ مرکب به صورت پر یا پنجه روی ساقه قرار می‌گیرند. در آرایش نوع پر، برگ‌ها شبیه شانه‌ای در دو طرف رگبرگ اصلی جای می‌گیرند، مانند برگ درخت گردو و زبان گنجشک. برگچه‌های برگ‌های مرکب پنجه‌ای از انتهای دمبرگ می‌رویند، مانند برگ شبدر. در برخی از گیاهان، برگچه‌ها به برگچه‌های کوچک‌تری تقسیم می‌شوند و این برگ‌ها را برگ مرکب دوگانه می‌نامند مانند برگ هویج و شبت (شوید). لبه و طرح رگبرگ‌های پهنک برگ‌ها گوناگون است. بعضی پهنک برگ‌ها دارای لبه صاف، بعضی دانه‌دار و بعضی کنگره‌دار هستند. لبه بیشتر برگ‌های باریک و سوزنی صاف است. لبه پهنک بیشتر گیاهانی که در منطقه اقلیمی استوایی و نیمه استوایی می‌رویند نیز صاف است. لبه پهنک درختانی مانند، پرتقال، نارون و گیلاس دانه‌دار است و همچنین روی آن‌ها روزنه‌هایی نیز وجود دارد که بخشی از آب اضافی گیاه از راه این روزنه‌ها خارج می‌شود. لبه برگ برخی از گیاهان، مانند توت سفید و بلوط جنگلی، کنگره‌دار است.

شکل‌های برگ‌ها ویرایش

در دانش گیاه‌شناسی برگ‌ها به شکل‌های زیر دسته‌بندی می‌شوند (لاتین، به همراه توضیح انگلیسی و ترجمه پارسی آن):

  1. Acicular (acicularis): Slender and pointed, needle-like (سوزنی‌شکل)
  2. Acuminate (acuminata): Tapering to a long point (هرمی‌شکل)
  3. Acute: pointed, having a short sharp apex angled less than ۹۰° (دارای زاویهٔ تند کمتر از ۹۰ درجه)
  4. Aristate (aristata): Ending in a stiff, bristle-like point (دارای انتهای زبر و محکم)
  5. Asymmetrical: With the blade shape different on each side of the midrib (با اجزاء گوناگون تیغی‌شکل)
  6. Basal: arising from the crown, bulb, rhizome or corm, etc. as opposed to cauline (تاجی‌شکل، چراغی‌شکل)
  7. Bipinnate (bipinnata): Each leaflet also pinnate (پرمانند)
  8. Caudate: tailed at the apex (دم‌دار)
  9. Cauline: borne on the stem as opposed to basal (موازی با ساقه)
  10. Compound: Not simple; the leaf is broken up into separate leaflets, and the leaf blade is not continuous (دارای برگچه)
  11. Cordate (cordata): Heart-shaped, with the petiole or stem attached to the cleft (قلب‌مانند)
  12. Cuneate (cuneata): Triangular, stem attaches to point (مثلثی، وصل‌شده توسط سطح برگ)
  13. Deltoid (deltoidea) or deltate: Triangular, stem attaches to side (مثلثی، توسط کناره‌های برگ)
  14. Digitate (digitata): Divided into finger-like lobes (انگشت‌دار)
  15. Elliptic (elliptica): Oval, with a short or no point (بیضی‌شکل)
  16. Entire: having a smooth margin without notches or indentations (دارای یک لبه صاف و بدون شکاف و دندانه)
  17. Falcate (falcata): Sickle-shaped (داسی‌شکل)
  18. Fenestrate (fenestrata) "windowed" with holes (e.g. Monstera deliciosa or Aponogeton fenestralis), or window-like patches of translucent tissue. (cf Perforate) (پنجره‌مانند)
  19. Filiform (filiformis): Thread- or filament-shaped (رشته‌ای‌شکل)
  20. Flabellate (flabellata): Semi-circular, or fan-like (نیم‌دایره‌ای یا بادبزن‌مانند)
  21. Hastate, spear-shaped (hastata): Pointed, with barbs, shaped like a spear point, with flaring pointed lobes at the base (نیزه‌مانند)
  22. Laciniate: Very deeply lobed, the lobes being very drawn out, often making the leaf look somewhat like a branch or a pitchfork (چنگال‌مانند)
  23. Laminar: Flat (like most leaves) (صاف، مانند اکثر برگ‌ها)
  24. Lance-shaped, lanceolate (lanceolata): Long, wider in the middle (دراز و دارای میانه‌ای پهن)
  25. Linear (linearis): Long and very narrow (دراز و باریک)
  26. Lobed (lobata): With several points (دارای چندین نوک)
  27. Mucronate: Ending abruptly in a sharp point (دارای انتهایی تیز)
  28. Obcordate (obcordata): Heart-shaped, stem attaches to tapering point (قلب‌مانند)
  29. Oblanceolate (oblanceolata): Top wider than bottom (انتهای فوقانی عریض تر از انتهای تحتانی)
  30. Oblong (oblongus): Having an elongated form with slightly parallel sides (کشیده و قرینه)
  31. Obovate (obovata): Teardrop-shaped, stem attaches to tapering point (اشکی‌شکل)
  32. Obtuse (obtusus): With a blunt tip (دارای لبهٔ بی‌نوک)
  33. Orbicular (orbicularis): Circular (دایره‌ای)
  34. Ovate (ovata): Oval, egg-shaped, with a tapering point (تخم‌مرغی‌شکل)
  35. Palmate (palmata): Consisting of leaflets or lobes radiating from the base of the leaf. (پنجه‌ای)
  36. Pedate (pedata): Palmate, with cleft lobes (نخلی‌شکل)
  37. Peltate (peltata): Rounded, stem underneath (دوار)
  38. Perfoliate (perfoliata): Stem through the leaves (ساقه از میان برگ ردشده)
  39. Perforate (perforata): marked with patches of translucent tissue, as in Crassula perforata and Hypericum perforatum, or perforated with holes (cf "Fenestrate") (مشخص‌شده با تکه‌های بافت شفاف)
  40. Pinnate (pinnata): Two rows of leaflets (شانه‌ای)
  41. Odd-pinnate, imparipinnate: Pinnate with a terminal leaflet (شانه‌ای فرد یا شانه‌ای بسته)
  42. Paripinnate, even-pinnate: Pinnate lacking a terminal leaflet (شانه‌ای زوج یا شانه‌ای باز)
  43. Pinnatifid and pinnatipartite: Leaves with pinnate lobes that are not discrete, remaining sufficiently connected to each other that they are not separate leaflets. (دارای برگچه‌های پیوسته و پرمانند)
  44. Bipinnate, twice-pinnate: The leaflets are themselves pinnately-compound (دوشانه‌ای یا شانه‌ای مضاعف)
  45. Tripinnate, thrice-pinnate: The leaflets are themselves bipinnate (سه‌شانه‌ای)
  46. Tetrapinnate: The leaflets are themselves tripinnate. (چهارشانه‌ای)
  47. Pinnatisect (pinnatifida): Cut, but not to the midrib (it would be pinnate then) (برش‌خورده)
  48. Serenoa repens showing pleated elliptic leaves of seedling and pleated palmate leaves of mature plant (بیضوی‌شکل)
  49. Plicate (plicatus, plicata): folded into pleats, usually lengthwise, serving the function of stiffening a large leaf. (تاشده به شکل بیضی)
  50. Pungent: Having hard, sharp points. (دارای انتهای تیز و زبر)
  51. Reniform (reniformis): Kidney-shaped (کلیه‌مانند)
  52. Retuse: With a shallow notch in a broad apex (با یک شکاف کم‌عمق در انتهای فوقانی عریضش)
  53. Rhomboid (rhomboidalis): Diamond-shaped (الماس‌مانند)
  54. Round (rotundifolia): Circular (گرد یا دایره‌مانند)
  55. Sagittate (sagittata): Arrowhead-shaped (تیرکمانی)
  56. Simple: Leaf blade in one continuous section, not divided into leaflets (not compound) (به شکل یک تیغ کلی)
  57. Spear-shaped (نیزه‌مانند)
  58. Spatulate, spathulate (spathulata): Spoon-shaped (قاشق‌مانند)
  59. Subulate (subulata): Awl-shaped with a tapering point (درفش‌مانند)
  60. Subobtuse (subobtusa): Somewhat blunted, neither blunt nor sharp (نیمه‌تیز)
  61. Sword-shaped (ensiformis): Long, thin, pointed (دراز، باریک و ریز)
  62. Trifoliate (or trifoliolate), ternate (trifoliata): Divided into three leaflets (سه‌برگچه‌ای)
  63. Tripinnate (tripinnata): Pinnately compound in which each leaflet is itself bipinnate (سه‌شانه‌ای)
  64. Truncate (truncata): With a squared off end (با انتهای مربعی‌شکل)
  65. Unifoliate (unifoliata): With a single leaf (تک‌برگی)
Image Term Latin Refers principally to Description
  acicular acicularis whole leaf Slender and pointed, needle-like
  acuminate acuminatus leaf tip Tapering to a long point in a concave manner
  acute leaf tip or base Pointed, having a short sharp apex angled less than 90°
  apiculate apiculatus leaf tip Tapering and ending in a short, slender point
  aristate aristatus leaf tip Ending in a stiff, bristle-like point
asymmetrical whole leaf With the blade shape different on each side of the midrib
  attenuate attenuatus leaf base Having leaf tissue taper down the petiole to a narrow base and always having some leaf material on each side of the petiole
  auriculate auriculatus leaf base Having ear-shaped appendages reaching beyond the attachment to the petiole or stem (in case of a seated leaf)
  caudate caudatus leaf tip Tailed at the apex
cirrus, cirrate leaf tip Having a rachis that extends beyond the leaf blade or leaflets into a long whip-like extension or cirrus (common in climbing palms); antonym: ecirrate
  cordate, cordiform cordatus whole leaf or base Heart-shaped, with the petiole or stem attached to the notch
  cuneate cuneatus leaf base Triangular, wedge-shaped, stem attaches to point
cuneiform whole leaf Narrowly triangular, widest on the opposite end from the stem, with the corners at that end rounded
  cuspidate cuspidatus leaf tip With a sharp, elongated, rigid tip; tipped with a cusp
  deltoid, deltate deltoideus whole leaf Shaped like the Greek letter delta; triangular with stem attached to side
  digitate digitatus whole leaf A palmately compound leaf with leaflets, similar to palmate[۱]
ecirrate leaf tip Without a cirrus; antonym: cirrate
  elliptic ellipticus whole leaf Shaped like an ellipse (widest at mid-blade and with similar convex tapering towards apex and base), with a short or no point
  emarginate emarginatus leaf tip Slightly indented at the tip
  ensiform ensiformis whole leaf Shaped like a sword; long and narrow with a sharp pointed tip
  falcate falcatus whole leaf Sickle-shaped
  fenestrate fenestratus leaf surface features Large openings through the leaf; see perforate; sometimes used to describe leaf epidermal windows
  filiform filiformis whole leaf Thread- or filament-shaped
  flabellate flabellatus whole leaf Semi-circular or fan-like
  hastate hastatus whole leaf or base Spear-shaped: pointed, with barbs, shaped like a spear point, with flaring pointed lobes at the base
  laciniate lacinatus whole leaf Very deeply lobed with the lobes being very drawn out and often making the leaf look somewhat like a branch or a pitchfork
laminar 3-D shape Flat (like most leaves)
  lanceolate lanceolatus whole leaf Long, wider in the middle, shaped like a lance tip
  linear linearis whole leaf Long and very narrow like a blade of grass
  lobed lobatus whole leaf Being divided by clefts; may be pinnately lobed or palmately lobed
  lorate loratus whole leaf Having the form of a thong or strap
  lyrate lyratus whole leaf Shaped like a lyre, pinnately lobed leaf with an enlarged terminal lobe and smaller lateral lobes. See also List of lyrate plants.
  mucronate mucronatus leaf tip Ending abruptly in a small sharp point as a continuation of the midrib[۲]
  multifid multi + findere whole leaf Cleft into many parts or lobes
  obcordate obcordatus whole leaf Heart-shaped, stem attaches at the tapering end
  oblanceolate oblanceolatus whole leaf Much longer than wide and with the widest portion near the tip; reversed lanceolate
  oblique leaf base Asymmetrical leaf base, with one side lower than the other
  oblong oblongus whole leaf Having an elongated form with slightly parallel sides; roughly rectangular
  obovate obovatus whole leaf Teardrop-shaped, stem attaches to the tapering end; reversed ovate
obtrullate whole leaf Reversed trullate; the longer sides meet at the base rather than the apex.
  obtuse obtusus leaf tip or base Blunt, forming an angle > 90°
  orbicular orbicularis whole leaf Circular
  ovate ovatus whole leaf Egg-shaped, with a tapering point and the widest portion near the petiole
  palmate palmatus whole leaf Palm-shaped, i.e. with lobes or leaflets stemming from the leaf base[۳]
  palmately lobed palmatus whole leaf Lobes spread radially from a point[۴]
  palmatifid palma + findere whole leaf Palm-shaped, having lobes with incisions that extend less than halfway toward the petiole
  palmatipartite palma + partiri whole leaf Having palmate lobes with incisions that extend over halfway toward the petiole
  palmatisect palma + secare whole leaf Having palmate lobes with incisions that extend almost up, but not quite to the petiole.
  pandurate panduratus whole leaf Fiddle-shaped; obovate with a constriction near the middle.
  pedate pedatus whole leaf Palmate, with cleft lobes[۵]
  سپروار peltatus stem attachment A round leaf where the petiole attaches near the center, e.g. a lotus leaf
  perfoliate perfoliatus stem attachment With the leaf blade surrounding the stem such that the stem appears to pass through the leaf
  perforate perforatus leaf surface features Many holes, or perforations, on leaf surface. Compare with fenestrate.
  pinnately lobed pinna + lobus whole leaf Having lobes pinnately arranged on the central axis
  pinnatifid pinna + findere whole leaf Having lobes with incisions that extend less than halfway to the midrib
  pinnatipartite pinnatus + partiri whole leaf Having lobes with incisions that extend more than halfway to the midrib
  pinnatisect pinnatus + sectus whole leaf Having lobes with incisions that extend almost to, or up to, the midrib
  plicate plicatus 3-D shape Folded into pleats, usually lengthwise, serving the function of stiffening a large leaf
  reniform reniformis whole leaf Shaped like a kidney, with an inward curve on one side
  retuse leaf tip With a shallow notch in a round apex
  rhomboid, rhombic rhomboidalis whole leaf Diamond-shaped
  rounded rotundifolius leaf tip or base Circular, no distinct point
semiterete 3-D shape Rounded on one side and flat on the other
  sinuate sinuatus 3-D shape Circularly-lobed leaves
  sagittate sagittatus whole leaf Arrowhead-shaped with the lower lobes folded, or curled downward
  spatulate spathulatus whole leaf Spoon-shaped; having a broad flat end which tapers to the base
  spear-shaped hastatus whole leaf See hastate.
  subobtuse subobtusus leaf tip or base Somewhat blunted; neither blunt nor sharp
  subulate subulatus leaf tip Awl-shaped with a tapering point
  terete 3-D shape Cylindrical with a circular or distorted circular cross-section and a single surface wrapping around it with no grooves or ridges. Subterete means the leaves are not completely terete, as seen in various lichens and succulents.
  trullate whole leaf Shaped like a masonry trowel
  truncate truncatus leaf tip or base With a squared-off end
undulate undulatus 3-D shape Wave-like
  unifoliate unifoliatus compound leaves With a single leaflet; it is distinct from a simple leaf by the presence of two abscission layers and often by petiolules and stipels.

نگارخانه ویرایش

جستارهای وابسته ویرایش

منابع ویرایش

  1. Index of Garden Plants, Mark Griffiths, Timber Press, 1992
  2. Mucronate بایگانی‌شده در ۲۰۱۶-۰۳-۰۳ توسط Wayback Machine, Answers.com, from Roget's Thesaurus.
  3. "palmate (adj. palmately)". GardenWeb Glossary of Botanical Terms. iVillage GardenWeb. 2006. Archived from the original on 13 February 2009. Retrieved 19 October 2008.
  4. Nelson, Randal C. (2009) [2012]. "Leaf description glossary". University of Rochester. Archived from the original on 1 August 2020. Retrieved 2 November 2017.
  5. "Pedate leaf". Retrieved 24 February 2014.

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