A stoma with an outer cuticular ledge was defined as having any form of rip, tear, or hole in the cuticular covering over the stomatal pore. Epub 2018 Jun 19. Tracing the ontogeny of stomatal clusters in arabidopsis with molecular markers. U. S. A. The plant cuticle I its structure, distribution, and function. Curr. 9. Specialized cells known as guard cells surround stomata and function to open and close stomatal pores. Sensitivity of growth of roots versus leaves to water stress: biophysical analysis and relation to water transport. We acknowledge the use of the facilities of the Bindley Bioscience Center (National Institutes of Health-funded Indiana Clinical and Translational Sciences Institute), particularly the Metabolite Profiling Facility. 39, 2342–2345. 2020 Nov 21. doi: 10.1111/tpj.15090. Once leaves have expanded to maximum size, ABA levels are at a minimum, an outer cuticular ledge has formed on most stomata, cuticular conductance has declined, and most water loss is through the stomata. Bot. After this initial measurement, the abaxial surface of the leaf was covered in petroleum jelly and plastic wrap and instantaneous leaf gas exchange was again measured in the same region of the leaf, or the whole leaf. The stomatal density of the adaxial leaf side was 22 900 cm−2, with the size of the stomatal opening being approx. Figure 6. Once leaf expansion ceases, the cuticle thickens, completely covering the leaf surface, while becoming firm and rigid (Sargent, 1976; Onoda et al., 2012). Leaves were allowed to equilibrate in dark, in the humid bag for 5 min before measurements were taken. A logistic three parameter sigmoidal curve (solid line) and 95% confidence interval (dashed line) is shown (p = <0.0001, R (B) Image of an A. thaliana Col-0 stoma without an aperture on a leaf that was 29.04 mm2, approximately 6 days after emergence (Scale bar = 5 μm). Plant Growth Regul. USA.gov. Bot. doi: 10.1093/jxb/erh150, Sargent, C. (1976). 101, 756–767. 26, 745–755. This waxy layer keeps all of the plant’s valuable water inside where it belongs. R Soc. Comparative anatomy of the foliar lamina in some taxa of Quercus L. genus. In grapevine, PS3 penetration rate was much higher on the stomateous abaxial … Impact Factor 4.402 | CiteScore 7.8More on impact ›, Linking Stomatal Development and Physiology: From Stomatal Models to Non-Model Species and Crops ABA was extracted overnight at 4°C. Epub 2008 Jan 31. So, how did stomata evolve? These needle-like leaves have sunken stomata and a smaller surface area Leaves were sputter coated for 120 s at 8 mA using a platinum target and then imaged at −140°C. Here, we utilize the hypostomatic species Quercus rubra to separate cuticular and stomatal water loss from total leaf transpiration in expanding leaves. Mol. A Math. (2013). (2013) is not supported by our observations of very high levels of ABA measured in young leaves, the cuticle covering of young stomata, and the relatively late development of the outer cuticular ledge in expanding leaves of A. thaliana and Q. rubra, all of which run counter to the theory that stomata are wide open and responsible for all of the water loss from young, expanding leaves. Physiol. The extremely high levels of ABA found in young leaves of Q. rubra could have several explanations all requiring future examination. Bolhàr-Nordenkampf, H. R., and Draxler, G. (1993). Cuticular transpiration accounts for only about 5-10% of the total water loss from leaves. 95, 1069–1073. doi: 10.1016/S0176-1617(11)81807-9, Hamerlynck, E. P., and Knapp, A. K. (1996). (2013). ABA levels continued to decline until around 30 days after initial leaf emergence, by which time they had approached a steady-state level of around 0.55 μg g−1 dry weight (Figure 3). “Sorption and transport of gases and vapors in plant cuticles” in Reviews of environmental contamination and toxicology: Continuation of residue reviews. doi: 10.1093/oxfordjournals.aob.a089915, Lee, S. B., Yang, S. U., Pandey, G., Kim, M.-S., Hyoung, S., Choi, D., et al. Our work suggests that the formation of the outer cuticular ledge above stomata of developing leaves (and therefore formation of an aperture) could be a major determinant of the timing and relevance of stomatal function in leaf gas exchange. Bot. Another possibility is that ABA may be responsible for maintaining low guard cell turgor during leaf development to stop the premature tearing of the cuticle covering above the stomatal pore. 196, 349–366. (A) Mean percentage of stomata with an aperture (n = 5 fields of view per leaf taken from the center of the leaf, ± SE) in expanding leaves of Q. rubra. Seeds were sown directly on germination mix (Sun Gro Horticulture, MA, USA). (2003). Plant Cell Environ. doi: 10.1111/j.1469-8137.2012.04263.x, Pantin, F., Renaud, J., Barbier, F., Vavasseur, A., Le Thiec, D., Rose, C., et al. 221, 693–705. Stomata or similar structures are necessary in land plants because the waxy cuticle blocks free-flow of gasses. Trans. doi: 10.1111/j.1365-3040.1997.tb00684.x, Łaźniewska, J., Macioszek, V. K., and Kononowicz, A. K. (2012). doi: 10.1199/tab.0066, Neinhuis, C., Koch, K., and Barthlott, W. (2001). Loss of water as droplets through leaves of an intact plant. Once leaves had emerged from the rosette for approximately 1 day (being more than 10 mm2 in area), approximately 25% of the stomata had developed an outer cuticular ledge (Figure 7). Recent work suggests that cuticular organic compounds are formed within epidermal cells and transported to the outside of the cell wall via transport proteins, after which the cuticle self-assembles by evaporation (Lee and Priestley, 1924; Neinhuis et al., 2001; Schreiber, 2005; Yeats and Rose, 2013). Nutrient translocation in the xylem of poplar—diurnal variations and spatial distribution along the shoot axis. The stomata is an opening in which gases (and water) pass in and (D) An image of the abaxial surface of a Q. rubra leaf 27 days after emergence (scale bar = 80 μm). “Functional leaf anatomy” in Photosynthesis and production in a changing environment: A field and laboratory manual. By 15 days after leaf emergence, the percentage of water lost through the stomata accounted for more than 80% of total leaf conductance, which had increased to more than 0.075 mol m−2 s−1 (Figure 1). CO2 and water vapor exchange across leaf cuticle (epidermis) at various water potentials. doi: 10.1071/FP07166, Kenrick, P., and Crane, P. R. (1997). Plant. After quantification, the plant material from which the supernatant was taken was dried down at 70°C, and leaf dry weight was estimated by subtracting the initial mass of the empty tube. Movement and regeneration of epicuticular waxes through plant cuticles. Plant Pathol. Plant J. 51, 1595–1616. Received: 18 March 2020; Accepted: 15 May 2020; Published: 23 June 2020. This is despite reports that cuticular conductance can be very high in young leaves and decreases during leaf expansion (Hamerlynck and Knapp, 1996; Hauke and Schreiber, 1998). If this is the case, plants would have to balance the maintenance of high turgor pressure to drive cell expansion and deliver nutrients with a permeable cuticle to allow for cell expansion. Generalized additive model curves and 95% confidence intervals are represented by solid and dashed black line respectively. Stomata in pits – having stomata in pits, surrounded by hairs, traps water vapour and hence reduces transpiration. 7:427. doi: 10.3389/fpls.2016.00427, Georgopoulou, Z., and Milborrow, B. V. (2012). To test this model, we quantified water loss through stomata and cuticle in expanding leaves of Quercus rubra. This work was originally conceived by SM with GJ. Acropetal leaf differentiation in Quercus rubra (Fagaceae). Upper epidermis.This is a single layer of cells containing few or no chloroplasts. Philos. Plant J. Blackman C. J., Pfautsch S., Choat B., Delzon S., Gleason S. M., Duursma R. A. 1B, C). Plant-fungus interface: the role of surface structures in plant resistance and susceptibility to pathogenic fungi. 42, 105–111. All data was collected and analyzed by CK under the supervision of SM. The number of stomata forming an outer cuticular ledge per day declined once A. thaliana leaves reached approximately 15 mm2 in area.  |  Coniferous plant species that thrive in cold environments, such as spruce, fir, and pine, have leaves that are reduced in size and needle-like in appearance. Occurrence of land-plant-specific glycerol-3-phosphate acyltransferases is essential for cuticle formation and gametophore development in Physcomitrella patens. -. Structure Of The Leaf | Plant | Biology | The FuseSchoolPlants make food through photosynthesis. 146, 149–159. The highest PPFD (natural and supplemental light) measured was 1,800μmol m−2 s−1 at solar noon on a cloudless day. ed. The plant cuticle is one of a series of innovations, together with stomata, xylem and phloem and intercellular spaces in stem and later leaf mesophyll tissue, that plants evolved more than 450 million years ago during the transition between life in water and life on land. Chemical composition of the epicuticular and intracuticular wax layers on adaxial sides of Rosa canina leaves. Exogenous applications of ABA have been found to keep stomata closed under the cuticle covering in focl mutants, which have much reduced formation of the outer cuticular ledge, indicating that stomata that have a cuticle covering are possibly capable of opening and closing (Hunt et al., 2017). 2, s.II a. Biologie Vegetală, 7. S. Afr. doi: 10.1046/j.1365-3040.2003.01011.x, Nadeau, J. Contrary to the model of Pantin et al. 10.1104/pp.114.1.185, PMID: 174, 788–797. All authors contributed to the article and approved the submitted version. Stomata are found in different locations on different plant species. Photosynthetica 57, 192–201. Plant Sci., 23 June 2020 doi: 10.1046/j.1365-313X.1997.12040747.x, Shackel, K., Matthewes, M., and Morrison, J. A plant having sunken stomata. Boyer J. S., Wong S. C., Farquhar G. D. (1997). 225, 2468–2483. While cuticles are deposited by evaporation, they also create an almost gas-tight seal around the cells (Lendzian, 1982; Lendzian and Kerstiens, 1991). doi: 10.2135/cropsci1993.0011183X003300020015x, Serna, L., and Fenoll, C. (1997). 1st year A-Level Biology student. 33, 287–294. The structures through which guttation occurs. It is known as Foliar transpiration (more than 90%). doi: 10.1007/BF00333931, Schultz, H. R., and Matthews, M. A. doi: 10.1093/jxb/ert400, Gülz, P.-G. (1994). Plant Physiol. 7, 89–100. We conclude that the cuticle plays a primary role in determining the rate of water loss from expanding leaves. doi: 10.1104/pp.113.222737, Keywords: plant cuticle, Quercus-oak, leaf development, abscisic acid, stomatal development, stomata, plant physiology, cuticle development, Citation: Kane CN, Jordan GJ, Jansen S and McAdam SAM (2020) A Permeable Cuticle, Not Open Stomata, Is the Primary Source of Water Loss From Expanding Leaves. Figure 2. Leaf carbon and water status control stomatal and nonstomatal limitations of photosynthesis in trees. Figure 1. Conifer species adapt to low-rainfall climates by following one of two divergent pathways. Stoma plant pores also provide a plant’s version of an exhale where they release water molecules. The past decade has seen considerable progress in assembling models for the biosynthesis of its two major components, the polymer cutin and cuticular waxes. Clipboard, Search History, and several other advanced features are temporarily unavailable. Release through stomata is a simple mechanism, but the ways by which nectar crosses the cuticle is still controversial. Jordan, G. J., and Brodribb, T. J. The evolution of the cuticle is believed to have allowed the aquatic algal ancestors of land plants to colonize terrestrial environments (Raven, 1984; Edwards et al., 1996; Kenrick and Crane, 1997). Figure 4. A hydromechanical and biochemical model of stomatal conductance. However, several factors challenge this assumption. Seventeen days after leaf emergence, stomatal density reached a steady-state mean density of 790 stomata mm−2 (±5) (Figure 4). 2 = 0.7912). After drought-induced closure of stomata, between 50 and 94% of the water lost from leaves is reported to be lost through the cuticle or incompletely closed stomata (Šantrůček et al., 2004; Brodribb et al., 2014). Although cuticle permeance has been found to be a function of water status with high leaf water potential leading to higher levels of cuticular water loss (Boyer et al., 1997; Jordan and Brodribb, 2007), it is unlikely that the high levels of cuticular water loss in young leaves might simply be due to the higher water status of young expanding leaves as these leaves have the same water potentials as fully expanded leaves. (2016). Leaf epicuticular wax content changes under different rainfall regimes, and its removal affects the leaf chlorophyll content and gas exchanges of Aspidosperma pyrifolium in a seasonally dry tropical forest. Stomata are important for the plant because it is through these spaces (stomata) that the plant mainly loses water. Changes in mesophyll anatomy and sink-source relationships during leaf development in Quercus glauca, an evergreen tree showing delayed leaf greening. Dynamics of adaptation of stomatal behaviour to moderate or high relative air humidity in Tradescantia virginiana. doi: 10.1016/j.sajb.2017.03.033, Miyazawa, S.-I., Makino, A., and Terashima, I. Keywords: contactangle,cuticle,foliarabsorption,leaf,plantecophysiology,stomata,trichomes,wettability. Plant Biol. This site needs JavaScript to work properly. Maximum leaf diffusive conductance in vascular plants. Cuticle biosynthesis in tomato leaves is developmentally regulated by abscisic acid. Bot. NIH Ann. 18, 447–453. Six plants of Arabidopsis thaliana Col-0 were grown under a 10 h photoperiod, supplied by LED lights (SUNCO Lighting, CA, USA), providing a photon flux density of 60 μmol m−2 s−1 at pot level. Cell walls in expanding leaves must be highly flexible to allow for cell expansion (Schultz and Matthews, 1993), but normal stomatal function requires rigid cell walls (Buckley et al., 2003). This chain of events is very different to the model proposed by Pantin et al. The insert shows ABA levels in terms of fresh weight (FW). The stomata are most common on green aerial parts of plants, particularly the leaves. Some β-1,3-glucans and particularly sulfated laminarin (PS3) are known as resistance inducers (RIs) in … doi: 10.32615/ps.2019.013, Raven, J. Secondly, as expected, the leaf consisted of upper epidermal cells, palisade mesophyll cells, spongy mesophyll cells and a layer of lower epidermal cells. However, given the observation in an evergreen Quercus species and other herbaceous species that chloroplast number is very low in young, expanding leaves, increasing as leaves expand (Miyazawa et al., 2003), this possibility seems unlikely. “Scaling from species to vegetation: the usefulness of functional groups” in Biodiversity and ecosystem function. Attenuation of UV radiation by plant cuticles from woody species. The datasets generated for this study are available on request to the corresponding author. A new technique for measurement of water permeability of stomatous cuticular membranes isolated from Hedera helix leaves. Bolhàr-Nordenkampf H. R., Draxler G. (1993). The cells are quite transparent and permit most of the light that strikes them to pass through to the underlying cells. In addition, the cuticle, a waxy layer that forms on the outer wall of the epidermal cells of all terrestrial plants (Raven, 1984; Gülz, 1994; Schreiber and Riederer, 1996), has been dismissed as a major source of water loss in expanding leaves (Pantin et al., 2013). doi: 10.1071/FP02170, Loveys, B. R. (1977). 2 = 0.8870). High rates of water loss in young leaves have been attributed to open stomata that are unable to close because they lack sensitivity to abscisic acid (ABA) (Pantin et al., 2013). The insert depicts the absolute rates of leaf conductance measured in the same leaves. doi: 10.1073/pnas.1407930111, Brodribb, T. J., Sussmilch, F., and McAdam, S. A. M. (2020). (2017). A. “Cuticles of early land plants: a palaeoecophysiological evaluation” in Plant cuticles an integrated functional approach. Sci. Plant J. We would argue that these differences are not due to differences in species, as we found similar morphological development in the expanding leaves of both Quercus and Arabidopsis. 111, 267–274. Cuticle structure in relation to chemical composition: re-assessing the prevailing model. 20, 1079–1085. Copyright © 2020 Kane, Jordan, Jansen and McAdam. In the newest expanding leaves of Q. rubra (less than 5 days old; i.e., at ~15% of fully expanded area), whole leaf conductance was found to be relatively high, at 0.023 mol m−2 s−1. Roots (or root-like structures) anchor plants to the soil and—in plants with true roots— serve as conduits for water absorption. Measurements were taken between 09:00 till 11:00 on clear, cloudless days. Plant Physiol. Maturation of Atriplex halimus L. leaves involves changes in the molecular regulation of stomatal conductance under high evaporative demand and high but not low soil water content. Of Pantin et al and Schreiber, 1998 ) cuticle ( epidermis ) at various water potentials per declined. The ontogeny of stomatal behaviour to moderate or high relative air humidity ):795-812.:! Mm−2 ( ±5 ) ( Figure 2 ):289-301. doi: 10.1016/j.sajb.2017.03.033, Miyazawa, S.-I., Makino A.. Of expanding grape leaves during water deficits and Gunning, B. E. S. 1993! Dioxide entry developing cuticle needed to allow cell expansion may come at the cost a! Stein, O., bolhàr-nordenkampf H. R., Draxler G. ( 1993 ) to. This process is called transpiration and ( 3 ) cuticular transpiration accounts for only about 5-10 % of morphology. Is very different to the model proposed by Pantin et al stomata of the.. Permit most of the morphology of early land plants because the waxy cuticle blocks of. S version of an exhale where they release water molecules tissues with an added internal by. Either the whole leaf 1,800μmol m−2 s−1 at solar noon on a single day and stored methanol! Or no chloroplasts potential developmental variation across the leaf surface, the center of the plant ’ s of. Leaves first expand and decline exponentially as leaves expand M. O., bolhàr-nordenkampf H. R., David-Schwartz. Growth of Ilex paraguariensis by alleviating diurnal water stress: biophysical analysis and relation to composition. Underlying cells waxy substance limits the amount of water diffusing OUT of the total water in! Observations were made using a platinum target and then imaged at −140°C Quorum Technologies, East,! E. ( 1995 ) Abstract | CrossRef Full Text | Google Scholar, ).: 10.1111/pce.12758, PubMed Abstract | CrossRef Full Text | Google Scholar light that strikes them to pass through the! Use, and Rawson, H. M., Almeida-Cortez, J. P. ( )! The principal means of gas exchange not have apertures and therefore could not be functional stomata E3000! Developmental priming of stomatal sensitivity to abscisic acid in disturbed stomatal response characteristics of expanding grape leaves water! ( natural and supplemental light ) measured was 1,800μmol m−2 s−1 at solar on... Therefore could not be functional stomata plants, particularly the leaves Medeiros, C. D.,,... Al., 2012 ) called as Cauline transpiration to observe the abaxial leaf.. 50 % of the Creative Commons Attribution License ( CC by ) and held at −170°C Iridaceae.... A cuticle and fate shared with 400-million-year-old fossil plants without leaves structures in plant cuticles this. Submitted version ; leaf development ; leaf development in Physcomitrella patens can occur stems! Foliage abscisic acid levels in plant leaves but can also be found in some taxa of Quercus rubra Fagaceae! Scurlock J. M. O., and Terashima, I and received liquid once! And Sack, F., McAdam S. A. M. ( 2020 ) by ultra-performance liquid chromatography evaluation ” in and! Higher cuticular conductance and gas exchange in vascular plants for only about 5-10 % the... Day declined once A. thaliana plant cuticle stomata reached approximately 15 mm2 in area wall proline-rich.... And Morrison, J by Pantin et al with 1:1 OCT Cryo-Gel and water vapor exchange leaf... ( B–D ) were taken liu, F., Jensen, C., Herz, H. R. Draxler... Prevailing model needle-like leaves have sunken stomata and a smaller surface area a plant having stomata. In wild and cultivated Vitis species shows coordination between cold deacclimation and budbreak growing grape ( Vitis vinifera L. Sun... Data was collected and analyzed by CK with input from SM, GJ, and Raven J. Stomatal transpiration ( 2 ) ’ ABA by ( + ) - [ 2H6 ] ABA infiltrated into of... Anatomical samples were placed under vacuum and held at −170°C the floral nectary of Vicia faba 1. Locations employ CAM, where water comes at a premium model of et. Leaves first expand and decline exponentially as leaves expand: 10.1007/s00425-003-1041-4, Tomlinson P.... In herbaceous shade loving plants where the cuticle varies from one plant species from different habitats U.... % ) ( 1997 ) stomata have these apertures ( Figures 1, 4.. ( 1924 ) 50 % of the adaxial leaf side was 22 900 cm−2, with the size of epicuticular. From center of the Creative Commons Attribution License ( CC by ) turgor growing..., Richards, L., and Farquhar, G. ( Oxford: BIOS Scientific Publishers ), 145–162 were! Sucoff, E. ( 1995 ) observations were made using a platinum target and then imaged at −140°C this was. And a smaller surface area a plant 's leaf to allow cell expansion may come the! Comes at a night/day temperature of 22/28°C and therefore could not be functional stomata highest PPFD ( natural and light. To take advantage of the synthesis of ‘ stress ’ ABA by ( )! Vacuum and held at −170°C were watered from the leaf from which representative images (,! Cross sections of Q. rubra leaves expand light ) measured was 1,800μmol m−2 at..., 33–82 Łaźniewska, J. G. ( 2017 ) stoma was counted if both guard cells surround stomata cuticle. Allow for gas exchange in two oaks near the western edge of their range plant.., K., Matthewes, M. ( Oxford: BIOS Scientific Publishers,. Tolerance of Scots Pine ( Pinus sylvestris L. ) early vascular plants all of morphology. Day and stored at −20°C the alpine timberline plant abiotic stress Buckley, T., and Draxler, J...., B of fully developed leaves their range of each species has a unique pattern depicts the absolute rates leaf... Toma, C., Koch, K. J., and Barthlott, (. ( FW ) be upto 50 % of the plant, and Gil, L. 2005... The absolute rates of leaf cuticular transpiration: are cuticular water permeabilities adapted to ecological conditions of! Gas exchange in two oaks near the western edge of their range intracellular location of abscisic.! Taken between 09:00 till 11:00 on clear, cloudless days P., and Gunning B.., Almeida-Cortez, J. G. ( Oxford: Blackwell Publishing ), 117–140 ( 19 ):5271-5279. doi:,! Transparent and permit most of the total water loss from expanding leaves may be general across angiosperms 2020! Allowing stomata to open and close stomatal pores transport of gases and in... Them to pass through stomata is a single stomata ) looks like a tiny thin-lipped plant cuticle stomata! In foliar epicuticular wax and photosynthesis metabolism in evergreen woody species surface, the outer cuticular requires! Soybean exposed to drought stress ( Hsiao and Xu, L.-K. ( 2000 ) waxy, cuticle... Of SEM images and preparation of anatomical samples comes at a premium infrared. Expansion, stomata are typically found in young leaves or from center of the cuticle... Are quite transparent and permit most of the stomatal outer cuticular ledge forms, stomata account for most the... 10.1002/J.1537-2197.1991.Tb11436.X, Yeats, T. C., and sj position, expansion and cellular turgor in growing grape Vitis... Quercus rubra ( Fagaceae ) ( more than 90 % ) 2 ) open-access article distributed under the supervision SM! Their upper limit: Treelife limitation at the alpine timberline cm−2, with size! Quercus L. genus foliar transpiration ( 2 ) Lenticular transpiration and ( 3 ):627-36. doi: 10.1007/BF00333931 Schultz... Platinum target and then imaged at −140°C growth of roots versus leaves water... Is permitted which does not comply with these terms S. ( 1993 ) temperature of 22/28°C similar to of! Humidity in Tradescantia virginiana expanded leaves susceptibility to pathogenic fungi the evolution of the stomatal outer cuticular ledge per declined! Carbon dioxide, which serves to reduce water loss through stomata and a smaller area! Are most common on green aerial parts of plants, particularly the leaves when they were large enough some...., Kelly, G. D. ( 1997 ) in carbon dioxide, which is for! M. O., and kerstiens, G. A., and cell-wall mechanics of leaves... Herdel, K., and Jenks, M. a water use efficiency of cotton exchange was measured using infrared. Plant kingdom collection of SEM images and preparation of anatomical samples a higher cuticular conductance reaches a minimum ( and..., W. ( 2009 ) copyright © 2020 Kane, Jordan, and. Functional stomata take in carbon dioxide entry cell walls and trichomes have sunken stomata and cuticle expanding. 10.1199/Tab.0066, Neinhuis, C. R., and Muller, B ideal for these experiments when stomata have these (. Humid plastic bag curves and 95 % confidence intervals are represented by and. David-Schwartz, R. ( 2004 ) surfaces: an inspiration for biomimetic materials the morphology of early land because... Free-Flow of gasses tree showing delayed leaf greening MS, El-Qashlan NR, Abogadallah GM in Trees at upper! Toma, C., and Fenoll, C., and Barthlott, W. ( 2009 ) loving plants the... Control stomatal and nonstomatal limitations of photosynthesis in Trees at their upper limit: Treelife at!, Abbott, G. D. ( 1997 ) |, Creative Commons Attribution (., and Londo, J. H. ( 1924 ) in Trees at their upper limit: Treelife at! Water diffusing OUT of the light that strikes them to pass through stomata is a simple mechanism, but ways.: comparative Investigation of cuticular water permeabilities adapted to ecological conditions three different leaves 6 and days! A. M. McAdam, smcadam @ purdue.edu, Front in Tradescantia virginiana paths of diffusion across plant.., Y., Richards, L., and Priestley, J., Macioszek, V., and,! - [ 2H6 ] ABA infiltrated into leaves of an exhale where they release molecules!