Herbicide Dispersal Patterns: I. As a Function of Leaf Surface

The distribution pattern of MCPA ([(4-chloro-o-tolyl)oxy] acetic acid) on leaf surfaces of three species was studied using the cathodoluminescence detection mode of a scanning electron microscope. On low-wax-content sugarbeet (Beta vulgarisL.) leaves MCPA concentrated in the depressions over the anticlinal cell walls when applied at high volumes (748 and 374 L/ha). At low volumes (23 L/ha), numerous small deposits of MCPA were randomly distributed over both anticlinal and periclinal walls. These distinct patterns were independent of herbicide concentration. Regardless of spray volumes, MCPA remaining on the waxy leaf surfaces of cabbage (Brassica oleraceaL.) coalesced into small thick deposits. Large spray drops from high application volumes shattered on impact with the stellate hairs of turkey mullein (Eremocarpus setigerusBenth.) resulting in some MCPA reaching the leaf surface. Spray drops from low application volumes did not shatter but lodged on the hairs with very little reaching the leaf surface.

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Herbicide Dispersal Patterns: HI. as a Function of Formulation

Weed Science ◽

10.1017/s0043174500061841 ◽

1981 ◽

Vol 29 (2) ◽

pp. 224-229 ◽

Cited By ~ 17

Author(s):

F. D. Hess ◽

D. E. Bayer ◽

R. H. Falk

Keyword(s):

Sugar Beet ◽

Cell Walls ◽

Cynodon Dactylon ◽

Distribution Patterns ◽

Dispersal Patterns ◽

Commercial Formulation ◽

X Ray ◽

Leaf Surfaces ◽

Wettable Powder ◽

Scanning Electron

The distribution patterns of several herbicide formulations sprayed on adaxial leaf surfaces were determined using scanning electron microscopy coupled with cathodoluminescence and x-ray microanalysis. The sodium and amine salts of MCPA {[(4-chloro-o-tolyl) oxy] acetic acid} sprayed on sugar beet (Beta vulgarisL.) leaves appeared as discrete deposits above the anticlinal cell walls that represented the location of spray drops that adhered to the leaf. When the sodium salt was applied to bermudagrass [Cynodon dactylon(L.) Pers.], the pattern of distribution was the same; however, each deposit was significantly smaller. The iso-octyl ester of MCPA coalesced into numerous, small, thick deposits on the cuticle of sugar beet leaves. The distribution of a wettable powder formulation of atrazine [2-chloro-4-(ethylamino)-6-(isopropylamino-s-triazine] appeared as uniform deposits over the anticlinal and periclinal cell walls that represented the location of aqueous spray drops after application. When a flowable formulation of atrazine was applied, there was a significant preferential accumulation of the herbicide at the edges of the separate deposits. One commercial formulation of propanil (3′,4′-dichloropropionanilide) yielded deposits that were crystalline, one that was partially crystalline, and one that was noncrystalline.

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ROSE LEAF SURFACE - BLACKSPOT DISEASE RESISTANCE: A SCANNING ELECTRON MICROSCOPE VIEW

HortScience ◽

10.21273/hortsci.25.9.1093f ◽

1990 ◽

Vol 25 (9) ◽

pp. 1093f-1093

Author(s):

K.S. Reddy ◽

S.E. Newman ◽

J.A. Spencer ◽

R.N. Paul

Keyword(s):

Fine Structure ◽

Leaf Surface ◽

Physical Nature ◽

Fungal Spore ◽

Dynamic Nature ◽

Diplocarpon Rosae ◽

Leaf Surfaces ◽

Visual Concepts ◽

Resistant Genotypes ◽

Scanning Electron

Blackspot disease, caused by Diplocarpon rosae, is a devastating disease of garden roses. Most hybrid teas and floribundas are susceptible to this disease in contrast to many species roses, which are resistant. The basis of this resistance is not known. The first barrier to invasion by the pathogen is the outer surface of the leaf. The physical nature of this surface may influence the attempted infection, landing, germination and penetration by the fungal spore and may cause a failure of infection. The leaf surfaces of susceptible and resistant genotypes were observed using SEM that allowed examination of the fine structure of the leaf surface. The characteristics of the leaf surface topography including wax structures were pictorially compared and visual concepts developed in relation to the dynamic nature of the leaf surface in space and time as leaf is infected by the pathogen.

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Notes on leaf micromorphology of the rare herbaceous bamboo Buergersiochloa bambusoides Pilg. (Olyreae, Poaceae) from New Guinea and its taxonomic implications

PhytoKeys ◽

10.3897/phytokeys.172.59506 ◽

2021 ◽

Vol 172 ◽

pp. 135-143

Author(s):

Jamile F. Lima ◽

Kelly Regina B. Leite ◽

Lynn G. Clark ◽

Reyjane P. Oliveira

Keyword(s):

Leaf Surface ◽

New Guinea ◽

Abaxial Surface ◽

Leaf Micromorphology ◽

Stomatal Complexes ◽

Herbaceous Bamboos ◽

Leaf Surfaces ◽

Taxonomic Implications ◽

First Time ◽

Scanning Electron

We present notes on the leaf micromorphology of Buergersiochloa bambusoides, a rare species from New Guinea and included in Buergersiochloinae, one of three subtribes of the herbaceous bamboos (tribe Olyreae). We used scanning electron microscopy and light microscopy to analyze the microcharacters of both adaxial and abaxial leaf surfaces. Within the Olyreae, saddle-shaped silica bodies in both the costal and intercostal zones are considered unique to Buergersiochloinae. Simple, circular and very small papillae are observed on the adaxial surface, and for the first time, branched papillae on the abaxial surface are observed in B. bambusoides. On the abaxial surface, there are papillae on long cells associated with the stomatal complexes. Bicellular microhairs are the only trichomes present and they are found almost exclusively on the abaxial surface. The saddle-shaped silica bodies are the most taxonomically important among the microcharacters observed on the leaf surface of B. bambusoides.

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Glands on the foliar surfaces of tribe Cercideae (Caesapiniodeae, Leguminosae): distribution and taxonomic significance

Anais da Academia Brasileira de Ciências ◽

10.1590/0001-3765201520140151 ◽

2015 ◽

Vol 87 (2) ◽

pp. 787-796 ◽

Cited By ~ 8

Author(s):

JOAQUIM M. DUARTE-ALMEIDA ◽

MILENE S. CLEMENTE ◽

ROSANI C.O. ARRUDA ◽

ANGELA M.S.F. VAZ ◽

ANTONIO SALATINO

Keyword(s):

Species Delimitation ◽

Leaf Surface ◽

Relative Number ◽

Northeast Brazil ◽

Taxonomic Significance ◽

Volatile Oils ◽

Abaxial Leaf Surface ◽

Leaf Surfaces ◽

Infraspecific Taxa ◽

Scanning Electron

Large elongated glands occur on Cercideae leaf surfaces. Leaves of Bauhinia (55 taxa, 53 species), Cercis (1 species), Phanera (1 species), Piliostigma (2 species), Schnella (19 species) and Tylosema (1 species) were observed to determine location and relative number of glands. They were only observed on the abaxial leaf surface of 42 Bauhinia taxa. The glands were analyzed by light stereomicroscope and scanning electron microscopy. They are large (up to 270 µm long and 115 µm wide) and multicellular, containing lipophilic substances, probably volatile oils. Presence or absence and density of the glands in species of Bauhinia may be useful to determine species delimitation or distinction among infraspecific taxa. Higher density of glands is more common in species from "cerrado" (a savanna ecosystem) and "caatinga" (a semiarid ecosystem from northeast Brazil) areas. Bauhinia species devoid of foliar glands are frequently from humid forests.

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Leaf characteristics and surfactants affect primisulfuron droplet spread in three broadleaf weeds

Weed Science ◽

10.1614/ws-05-019r.1 ◽

2006 ◽

Vol 54 (1) ◽

pp. 16-22 ◽

Cited By ~ 16

Author(s):

Debanjan Sanyal ◽

Prasanta C. Bhowmik ◽

Krishna N. Reddy

Keyword(s):

Leaf Surface ◽

Epicuticular Wax ◽

Distilled Water ◽

Weed Species ◽

Spray Droplet ◽

Common Lambsquarters ◽

Leaf Surfaces ◽

Droplet Behavior ◽

Wax Content ◽

Common Purslane

Laboratory studies were conducted to examine the leaf surface, epicuticular wax content, and spray droplet behavior on common lambsquarters, common purslane, and velvetleaf. Adaxial and abaxial leaf surfaces were examined using scanning electron microscopy, and leaf wax was extracted and quantified for all three weed species. The spread of 1-μl droplets of distilled water, primisulfuron solution (without surfactant), primisulfuron solution with a nonionic low foam wetter/spreader adjuvant (0.25% v/v), and with an organosilicone wetting agent (0.1% v/v) was determined on the adaxial leaf surfaces of each of the weed species. Glands and trichomes were present on both the adaxial and abaxial leaf surfaces of velvetleaf. Common purslane had neither glands nor trichomes on either side of the leaf. Common lambsquarters did not have any glands or trichomes, but it had globular bladder hairs on both adaxial and abaxial leaf surfaces. Stomata were present on both adaxial and abaxial leaf surfaces in all three weed species. Common purslane had a much lower number of stomata per unit area of leaf as compared with velvetleaf or common lambsquarters. Common lambsquarters had the highest epicuticular wax content on the leaf surface (274.5 μg cm−2), followed by common purslane (153.4 μg cm−2) and velvetleaf (7.4 μg cm−2). There were no significant variations in the spread of the 1-μl droplet of distilled water and primisulfuron (without adjuvant) among the species. Spread of primisulfuron droplets with surfactant was highest on the leaf surface of velvetleaf that had the lowest wax content. Droplet spread was greatest with organosilicone surfactant followed by the nonionic surfactant.

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ДЕЯКІ МІКРОМОРФОЛОГІЧНІ ОСОБЛИВОСТІ ATOCION LITHUANICUM (ZAPAŁ.) TZVEL. ТА A. ARMERIA (L.) RAF. ФЛОРИ УКРАЇНИ

Biological Bulletin of Bogdan Chmelnitskiy Melitopol State Pedagogical University ◽

10.15421/2015001 ◽

2015 ◽

Vol 5 (01) ◽

pp. 8 ◽

Cited By ~ 1

Author(s):

V. O. Martynyuk ◽

N. I. Karpenko ◽

O. M. Tsarenko

Keyword(s):

Electron Microscopy ◽

Leaf Surface ◽

Pollen Grains ◽

Southern Europe ◽

Anticlinal Wall ◽

Separate Species ◽

Exine Ornamentation ◽

Leaf Surfaces ◽

Seed Characteristics ◽

Scanning Electron

Atocion lithuanicum (Zapał.) Tzvel. (basionym Silene lithuanica Zapał.) is an endemic species of the Polesie, related and morphologically similar to A. armeria (L.) Raf., which naturally occurs in Central and Southern Europe, but is widely cultivated. In Ukraine A. lithuanicum is considered as separate species and included in different issues of nature conservation, but in Europe it is listed as synonym or variety of A. armeria. Thus, the purpose of our investigation was to examine micromorphological features of these taxa to distinguish them. Pollen grains, seeds and leaf surfaces of both Atocion lithuanicum and A. armeria (L.) Raf. were investigated by scanning electron microscopy. Palynological distinctions between these taxa are associated with the ultrastructure of pollen grains, such as margin of a pollen (smooth or undulate), diameter of pores (3,04-5,22 (3,96±0,57) or 2,62-4,15 (3,47±0,32) µm), microechinate number on the pore (11-20 (25) or 7-14), exine ornamentation (acute, broadly conical spinule or obtuse spinule) and perforation diameter (0,1 or 0,2-0,3 µm). Seed characteristics such as dimensions (350-570 х 450-630 (468,78±49,2 х 544,84±51,39) in A. lithuanicum or 480-670 х 600-800 (595,67±48,04 х 706,67± 50,26) µm in A. armeria), shape (reniform-circular or reniform-triangular and reniform-circular), dimensions of exotesta cells in distal row (69-160 х 13-28,6 (116,52±21,9 х 20,72±3,99) or 95,6-202,7 х 7,8-40,5 (143,31±27,3 х 28,76±5,05) µm), the number of anticlinal wall teeth (15-24 or 19-29), papilla presence on periclinal wall of lateral and dorsal surfaces (common absent or scarce weakly expressed in A. lithuanicum or usually strongly expressed in A. armeria) also differ these taxa. Epicuticular wax projections are of different size and shape even on the same lamina, so no significant differences in the leaf surface microcharacteristics were observed. Thereby, new micromorphological distinctions associated with the ultrastructure of pollen grains and the seeds were demonstrated, which allows to distinguish these taxa. Key words: Atocion lithuanicum, A. armeria, SЕМ, pollen, seed, lamina

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Low-temperature Scanning Electron Microscopy and Physical-Chemical investigations of leaf surface characteristics

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100135265 ◽

1990 ◽

Vol 48 (2) ◽

pp. 332-333 ◽

Cited By ~ 1

Author(s):

R. Guggenheim ◽

E. Zuberbühler ◽

M. Düggelin ◽

J. Harr

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Low Temperature ◽

Leaf Surface ◽

Plant Protection ◽

Surface Characteristics ◽

Wetting Properties ◽

Leaf Surfaces ◽

Temperature Scanning ◽

Scanning Electron

Plant protection agents (often incorrectly referred to as ‘pesticides’) mostly are targeted at plant surfaces either to protect them against pathogens and parasites or to destroy the treated plants in the case of herbicides. Many times, more than one species of plants are involved, that respond differently to such applications.In any of the cases cited, a thorough knowledge of the leaf surface characteristics may help to explain desired or undesirable effects. Also the wetting properties of a spray applied to plants will likely influence the performance of the active ingredient involved. It is obvious that only the use of a whole array of different methods will allow an interpretation or a prediction of effects caused by the application of plant protection sprays.To get well preserved epicuticular wax structures of leaf surfaces we used low-temperature scanning electron microscopy (LTSEM). Fresh cut samples were immediatly frozen in liquid nitrogen, transferred into a Balzers SCU 020 cryopreparation unit attached to an SEM Cambridge Mk II A.

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Influence of leaf surface micromorphology, wax content, and surfactant on primisulfuron droplet spread on barnyardgrass (Echinochloa crus-galli) and green foxtail (Setaria viridis)

Weed Science ◽

10.1614/ws-05-173r.1 ◽

2006 ◽

Vol 54 (4) ◽

pp. 627-633 ◽

Cited By ~ 29

Author(s):

Debanjan Sanyal ◽

Prasanta C. Bhowmik ◽

Krishna N. Reddy

Keyword(s):

Leaf Area ◽

Leaf Surface ◽

Unit Area ◽

Wetting Agent ◽

Adaxial Leaf Surface ◽

Green Foxtail ◽

Abaxial Leaf Surface ◽

Leaf Surfaces ◽

Spread Area ◽

Wax Content

Laboratory studies were conducted to examine the leaf surface, epicuticular wax content, and spread area of primisulfuron spray droplet with and without surfactant on leaf surface of barnyardgrass and green foxtail. Adaxial and abaxial leaf surfaces were examined using scanning electron microscopy and leaf wax was extracted and quantified. The spread of 1-μl droplets of distilled water, primisulfuron solution (without surfactant), primisulfuron solution with a nonionic low foam wetter/spreader adjuvant (0.25% v/v), and with an organosilicone wetting agent (0.1% v/v) was determined on the adaxial leaf surfaces of each of the weed species. Stomata and trichomes were present on adaxial and abaxial leaf surfaces in both species. Green foxtail had more stomata per unit area on the adaxial as compared to the abaxial leaf surface. Barnyardgrass had more stomata on the abaxial than on the adaxial leaf surface. There was no significant variation in the number of trichomes per unit leaf area of green foxtail, and the number of prickles per unit area of leaf was significantly higher in adaxial than the abaxial leaf surface, in both young and old leaves. In barnyardgrass, there were more trichomes on abaxial than adaxial leaf surface. The mean value of the wax content per unit of leaf area in barnyardgrass and green foxtail was 35.9 μg cm−2and 19.1 μg cm−2, respectively. On both species primisulfuron with a nonionic surfactant had more spread area than that without a surfactant, and the spread was even greater with organosilicone wetting agent. The spread area of primisulfuron droplet was higher on the leaf surface of barnyardgrass than on green foxtail when surfactant was added.

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APPLICATIONS OF COPPER-BASED FUNGICIDES AND INFESTATIONS OF Leucoptera coffeella (Guérin-Mèneville & Perrottet) IN COFFEE PLANTS

Coffee Science ◽

10.25186/cs.v14i1.1504 ◽

2019 ◽

Vol 14 (1) ◽

pp. 123

Author(s):

Paulo Henrique Siqueira Sabino ◽

Gian Otavio Alves Da Silva ◽

Adriano Bortolotti Da Silva ◽

Geraldo Andrade Carvalho

Keyword(s):

Leaf Surface ◽

Leaf Miner ◽

Coffee Plantation ◽

Leaf Surfaces ◽

Number Of Leaves ◽

Leucoptera Coffeella ◽

Coffee Plants ◽

Wax Content ◽

Different Sources

The present study aimed to evaluate the effects of applying fungicides with different sources of copper and of the number of applications on the occurrence of Leucoptera coffeella (Guérin-Menéville & Perrottet, 1842) (Lepidoptera: Lyonetiidae) and on the wax layer on leaves in a coffee plantation. Four applications of fungicides were carried out and the effects on the number of leaves mined by the insect and on the wax content on the leaf surface were evaluated. The copper-based fungicides increased the number of leaves mined by the leaf-miner and reduced the wax content on the coffee leaf surfaces in both periods studied.

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Herbicide Deposition on Leaf Surfaces

Weed Science ◽

10.1017/s004317450005654x ◽

1990 ◽

Vol 38 (3) ◽

pp. 280-288 ◽

Cited By ~ 72

Author(s):

F. Dan Hess ◽

Richard H. Falk

Keyword(s):

Cell Walls ◽

Leaf Surface ◽

Epicuticular Wax ◽

Crystalline Form ◽

Spray Solution ◽

Epidermal Surface ◽

Physical Form ◽

Leaf Surfaces ◽

Water Based ◽

Adverse Influence

Leaf surface morphology and physical characteristics of herbicide deposits on leaf surfaces can influence herbicide performance. Leaf surface topography, the degree and type of epicuticular wax formation, and the presence, type, and distribution of trichomes all influence the distribution of a given herbicide formulation sprayed onto a leaf surface. Depressions above anticlinal cell walls accumulate herbicide, thus lessening uniform distribution. As the amount of particulate wax increases, the size of individual spray drop deposits on the leaf decreases, thus resulting in reduced coverage. In many instances the presence of trichomes reduces optimal epidermal coverage by intercepting spray drops before they reach the epidermal surface. Adjuvants reduce the adverse influence of leaf topography, epicuticular wax, and trichomes on herbicide distribution, but their use usually does not yield an even coating over the entire leaf surface. Many herbicides, in pure form, are solids (i.e., crystals) rather than liquids. For most applications, herbicides are dissolved, dispersed, or emulsified in a water-based spray solution. After spraying, water and any solvents evaporate from the leaf surface and herbicides often return to their solid crystalline form. In the few cases that have been studied, less herbicide is absorbed when present on the leaf surface as a solid rather than as a liquid. In many instances, greater effectiveness of a postemergence herbicide may be obtained if attention is given to optimizing the distribution and physical form on sprayed leaf surfaces.

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