scholarly journals Variation in Leaf Anatomy of Pecan Cultivars from Three Ecogeographic Locations

2007 ◽  
Vol 132 (5) ◽  
pp. 592-596 ◽  
Author(s):  
Madhulika Sagaram ◽  
Leonardo Lombardini ◽  
L.J. Grauke
Keyword(s):  
Cell Density ◽  
Epidermal Cell ◽  
Stomatal Density ◽  
Carya Illinoinensis ◽  
Trichome Density ◽  
Stomatal Index ◽  
Cultivar Development ◽  
Natural Range ◽  
The Stability

An assessment of leaf anatomic traits of pecan [Carya illinoinensis (Wangenh.) C. Koch] cultivars (Pawnee, Mohawk, and Starking Hardy Giant) collected from three locations (Tifton, GA; Chetopa, KS; and Stillwater, OK) was conducted to provide an understanding of patterns of ecogeographical variation within the natural range. Acetate casts of representative leaves were prepared for microscopic characterization of epidermal traits (stomatal density, stomatal index, and epidermal cell density). There were differences among the three pecan cultivars at the same location, but there were no differences in stomatal density within the same cultivar grown at three distinct locations. The stomatal density of ‘Pawnee’ leaves (404 stomata/mm2) was intermediate between that of ‘Mohawk’ (363 stomata/mm2) and ‘Starking Hardy Giant’ (463 stomata/mm2). ‘Pawnee’ had the greatest epidermal cell density (2511 cells/mm2) whereas ‘Starking Hardy Giant’ showed the least (1414 cells/mm2). Within a location, stomatal index differed significantly among cultivars, with ‘Starking Hardy Giant’ having a greater stomatal index than the other two cultivars. There were no differences in stomatal index across locations. ‘Mohawk’ had the greatest trichome density (18.92 trichomes/mm2) whereas ‘Starking Hardy Giant’ had the lowest (9.6 trichomes/mm2). The study suggests that differences in stomatal density and epidermal cell density in pecans are cultivar specific rather than being determined by environmental factors. The stability of certain leaf anatomic characteristics, such as stomatal and epidermal cell density, for pecan cultivars grown at different locations confirms that these traits can be used for screening provenances with desirable leaf anatomic characteristics for breeding and cultivar development.

scholarly journals Variation in Leaf Anatomical Traits of Pecan Cultivars

HortScience ◽  
2006 ◽  
Vol 41 (4) ◽  
pp. 999E-1000
Author(s):  
Madhulika Sagaram ◽  
Leonardo Lombardini ◽  
Larry Grauke
Keyword(s):  
Geographic Variation ◽  
Cell Density ◽  
Epidermal Cell ◽  
Stomatal Density ◽  
Epidermal Cells ◽  
Stomatal Index ◽  
Natural Range

An assessment of anatomical traits of pecan cultivars (`Pawnee', `Mohawk', and `Starking hardy giant') collected from three locations (Tifton, Ga.; Chetopa, Kans.; and Stillwater, Okla.) was conducted at Texas A&M University. The objective of the study was to provide an understanding of patterns of geographic variation within the natural range for anatomical (stomatal density, stomatal index, and epidermal cell density) traits. Microscopy using acetate casts was used as the means to investigate the patterns of variation in the epidermal characteristics of pecan leaf. `Starking hardy giant' had the greatest number of stomates/cm2 (46,229, 47,807, and 45,990 at Tifton, Chetopa, and Stillwater, respectively) while `Mohawk' had the least (37,397, 36,217, and 35,305). `Pawnee' had the greatest number of epidermal cells/cm2 (251,806, 250,098 and 254,883 at Tifton, Chetopa, and Stillwater, respectively) while `Starking hardy giant' had the least (141,699, 138,405, and 142,155). Differences in stomatal index were observed between the three cultivars at Tifton and Stillwater. No differences in stomatal index were observed between `Pawnee' and `Mohawk' at Chetopa. The study showed that stomatal density as well as epidermal cell density of all the tested cultivars were significantly different (P < 0.05) at a particular location but no differences were observed in a given cultivar grown at different locations.

scholarly journals Variation in Anatomical Characteristics in Leaves of Pecan Seedstocks from Mexico and the United States

2011 ◽  
Vol 136 (2) ◽  
pp. 103-108 ◽  
Author(s):  
Madhulika Sagaram ◽  
Leonardo Lombardini ◽  
L.J. Grauke
Keyword(s):  
East Coast ◽  
Stomatal Density ◽  
The United States ◽  
Carya Illinoinensis ◽  
Annual Precipitation ◽  
Stomatal Index ◽  
Longitudinal Gradient ◽  
Water Losses ◽  
Single Location ◽  
Natural Range

Leaf anatomical traits of Mexican and U.S. pecan [Carya illinoinensis (Wangenh.) K. Koch] seedstocks grown in a single location were studied to determine patterns of ecogeographic variation within the natural range. Stomatal density was uniform among open-pollinated seedlings of a common maternal parent with twofold differences in stomatal density separating some seedstocks. There was an inverse relationship between stomatal density and epidermal cell density. Stomatal density and stomatal index of Mexican seedstocks were related to longitude and annual precipitation of origin. Stomatal density increased along the longitudinal gradient toward the east coast of Mexico; seedstocks originating from areas on the east coast of Mexico had greater stomatal density than seedstocks originating from the drier areas on the west coast. Stomatal density and stomatal index did not follow a pattern along latitude or longitude in the U.S. seedstocks. Although isotopic carbon (13C) discrimination did not vary greatly in Mexican seedstocks, the reduction in stomatal density in pecan trees from areas with reduced annual precipitation suggest the presence of an anatomical feature to reduce water losses.

scholarly journals Growth and leaf epidermal response of three Sesamum indicum varieties to industrial effluent irrigation

2017 ◽  
Vol 52 (1) ◽  
pp. 1-6 ◽  
Author(s):  
AA Abdul Rahaman ◽  
OM Olaniran ◽  
FA Oladele
Keyword(s):  
Seedling Growth ◽  
Stomatal Density ◽  
Industrial Effluent ◽  
Industrial Effluents ◽  
Sesamum Indicum ◽  
Proper Treatment ◽  
Trichome Density ◽  
Stomatal Index ◽  
Stomatal Size ◽  
Epidermal Features

The effect of industrial effluents was studied with respect to growth and leaf anatomy of three Sesamum indicum varieties (NGB 00931, NGB 00937 and NGB 00939). Industrial effluents (25%, 50%, 75% and 100%) from two industries are used to irrigate the plants. Although, the control plants possessed larger leaves and longer stems than the effluent-treated plants, at lower concentration, the plant growth is relatively higher. Gradual decrease in the germination of seeds and seedling growth with increase in effluent concentration was observed. The best germination and seedling growth was observed at the 25% concentration. Leaf epidermal features (stomatal density, stomatal index, stomatal size, trichome density, tricome index, trichome size and number of epidermal cells) are more influenced in the effluent-treated plants than in the control plants from the Peace Standard Pharmaceutical Industry than in the effluent from the Global Soap & Detergent Industry. Thus the industrial effluents can be safely used for irrigation purposes with proper treatment and dilution at 25%.Bangladesh J. Sci. Ind. Res. 52(1), 1-6, 2017

Micromorphologie des épidermes foliaires chez quelques espèces de Medicago

1983 ◽  
Vol 61 (12) ◽  
pp. 3461-3470 ◽  
Author(s):  
Catherine Damerval
Keyword(s):  
Guard Cell ◽  
Stomatal Density ◽  
Epidermal Cells ◽  
Cell Length ◽  
Leaf Epidermis ◽  
Trichome Density ◽  
Stomatal Index ◽  
Annual Species ◽  
Abaxial Epidermis ◽  
Stomatal Complex

The micromorphology of the abaxial epidermis of the first and sixth leaf has been studied in seven annual species of Medicago L. The pattern of the epidermal cells and of the stomatal complex does not allow differentiation of the taxa. Three main types of trichomes are recognized on the two foliar levels; their localization on the first leaf epidermis allows identification of five taxa out of seven. Four quantitative variables are also examined: stomatal density, trichome density, guard cell length, and stomatal index. The variable having the best discriminant value is the guard cell length on the first leaf. It is possible to identify each of the seven species by a combination of two features: the localization of the types of trichomes on the first leaf and the stomatal density on the sixth leaf.

scholarly journals What is the influence of ordinary epidermal cells and stomata on the leaf plasticity of coffee plants grown under full-sun and shady conditions?

2010 ◽  
Vol 70 (4) ◽  
pp. 1083-1088 ◽  
Author(s):  
MF. Pompelli ◽  
SCV. Martins ◽  
EF. Celin ◽  
MC. Ventrella ◽  
FM. DaMatta
Keyword(s):  
Epidermal Cell ◽  
Stomatal Density ◽  
Land Plant ◽  
Epidermal Cells ◽  
Stomatal Index ◽  
Unit Leaf ◽  
Leaf Plasticity ◽  
Coffee Plants ◽  
Sun Leaves ◽  
Lower Irradiance

Stomata are crucial in land plant productivity and survival. In general, with lower irradiance, stomatal and epidermal cell frequency per unit leaf area decreases, whereas guard-cell length or width increases. Nevertheless, the stomatal index is accepted as remaining constant. The aim of this paper to study the influence of ordinary epidermal cells and stomata on leaf plasticity and the influence of these characteristics on stomata density, index, and sizes, in the total number of stomata, as well as the detailed distribution of stomata on a leaf blade. As a result, a highly significant positive correlation (R²a = 0.767 p < 0.001) between stomatal index and stomatal density, and with ordinary epidermal cell density (R²a = 0.500 p < 0.05), and a highly negative correlation between stomatal index and ordinary epidermal cell area (R²a = -0.571 p < 0.001), were obtained. However in no instance was the correlation between stomatal index or stomatal density and stomatal dimensions taken into consideration. The study also indicated that in coffee, the stomatal index was 19.09% in shaded leaves and 20.08% in full-sun leaves. In this sense, variations in the stomatal index by irradiance, its causes and the consequences on plant physiology were discussed.

TEM characterization of Au/Polysilicon interactions

1990 ◽  
Vol 48 (4) ◽  
pp. 650-651
Author(s):  
N. David Theodore ◽  
Leslie H. Allen ◽  
C. Barry Carter ◽  
James W. Mayer
Keyword(s):  
Solid Phase ◽  
Single Crystal Silicon ◽  
Chemical Vapor ◽  
Electrical Contacts ◽  
Silicon Substrates ◽  
Crystal Silicon ◽  
Transmission Electron ◽  
Polysilicon Films ◽  
The Stability

Metal/polysilicon investigations contribute to an understanding of issues relevant to the stability of electrical contacts in semiconductor devices. These investigations also contribute to an understanding of Si lateral solid-phase epitactic growth. Metals such as Au, Al and Ag form eutectics with Si. reactions in these metal/polysilicon systems lead to the formation of large-grain silicon. Of these systems, the Al/polysilicon system has been most extensively studied. In this study, the behavior upon thermal annealing of Au/polysilicon bilayers is investigated using cross-section transmission electron microscopy (XTEM). The unique feature of this system is that silicon grain-growth occurs at particularly low temperatures ∽300°C).Gold/polysilicon bilayers were fabricated on thermally oxidized single-crystal silicon substrates. Lowpressure chemical vapor deposition (LPCVD) at 620°C was used to obtain 100 to 400 nm polysilicon films. The surface of the polysilicon was cleaned with a buffered hydrofluoric acid solution. Gold was then thermally evaporated onto the samples.

Preparation and Characterization of β-glucosidase Films for Stabilization and Handling in Dry Configurations

2020 ◽  
Vol 21 (8) ◽  
pp. 741-747
Author(s):  
Liguang Zhang ◽  
Yanan Shen ◽  
Wenjing Lu ◽  
Lengqiu Guo ◽  
Min Xiang ◽  
...  
Keyword(s):  
Tensile Strength ◽  
Protein Function ◽  
Protein Stabilization ◽  
Functional Protein ◽  
Elongation At Break ◽  
Gelatin Films ◽  
The Stability ◽  
And Function ◽  
General Method

Background: Although the stability of proteins is of significance to maintain protein function for therapeutical applications, this remains a challenge. Herein, a general method of preserving protein stability and function was developed using gelatin films. Method: Enzymes immobilized onto films composed of gelatin and Ethylene Glycol (EG) were developed to study their ability to stabilize proteins. As a model functional protein, β-glucosidase was selected. The tensile properties, microstructure, and crystallization behavior of the gelatin films were assessed. Result: Our results indicated that film configurations can preserve the activity of β-glucosidase under rigorous conditions (75% relative humidity and 37°C for 47 days). In both control films and films containing 1.8 % β-glucosidase, tensile strength increased with increased EG content, whilst the elongation at break increased initially, then decreased over time. The presence of β-glucosidase had a negligible influence on tensile strength and elongation at break. Scanning electron-microscopy (SEM) revealed that with increasing EG content or decreasing enzyme concentrations, a denser microstructure was observed. Conclusion: In conclusion, the dry film is a promising candidate to maintain protein stabilization and handling. The configuration is convenient and cheap, and thus applicable to protein storage and transportation processes in the future.

Effect of pH and temperature on the infectivity of human coronavirus 229E

1989 ◽  
Vol 35 (10) ◽  
pp. 972-974 ◽  
Author(s):  
Alain Lamarre ◽  
Pierre J. Talbot
Keyword(s):  
Incubation Period ◽  
Storage Conditions ◽  
Viral Infectivity ◽  
Human Coronavirus ◽  
Virus Growth ◽  
The Stability ◽  
And Storage ◽  
Influence Of Ph ◽  
Human Coronavirus 229E

The stability of human coronavirus 229E infectivity was maximum at pH 6.0 when incubated at either 4 or 33 °C. However, the influence of pH was more pronounced at 33 °C. Viral infectivity was completely lost after a 14-day incubation period at 22, 33, or 37 °C but remained relatively constant at 4 °C for the same length of time. Finally, the infectious titer did not show any significant reduction when subjected to 25 cycles of thawing and freezing. These studies will contribute to optimize virus growth and storage conditions, which will facilitate the molecular characterization of this important pathogen.Key words: coronavirus, pH, temperature, infectivity, human coronavirus.

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