Stomata in some species of genus Arum from the Eastern Slavonia and Baranya region

Biologia ◽  
2007 ◽  
Vol 62 (4) ◽  
Author(s):  
Mirjana Sabo ◽  
Tihana Marček ◽  
Tomislav Bačić ◽  
Ljiljana Krstin ◽  
Anita Lendel

AbstractTypes and the number of stomata in the following Arum species: Arum italicum Mill., Arum maculatum var. maculatum L. and Arum maculatum var. immaculatum L., Arum alpinum var. pannonicum Terpo. and Arum alpinum var. intermedium Schur. in three different locations in Zablaće, Normanci and Bilje were investigated. The most prevalent stomata type at both upper and lower epidermis for each Arum species was mostly stomata type paracytic, followed by hexacytic, tetracytic or brachyparacytic as far as locality is concerned. Helicocytic type was more prevalent in Arum alpinum var. pannonicum Terpo. and Arum alpinum var. intermedium Schur. at Bilje. Other stomata types were very rare. A striking regularity in the occurrence of stomata types was not found within a single species. Some stomata types, however, were found either at adaxial or abaxial epidermis or were not present at all. The number of stomata per square mm varied from 25 to 651. A statistically significant difference in the number of stomata per square mm at upper and lower epidermis among Arum species was determined in locations Zablaće and Normanci, whereas no statistically significant differences were found in location Bilje.

2020 ◽  
pp. 147-152
Author(s):  
Rainer W. Bussmann ◽  
Ketevan Batsatsashvili ◽  
Zaal Kikvidze ◽  
Narel Y. Paniagua-Zambrana ◽  
Manana Khutsishvili ◽  
...  
Keyword(s):  

Author(s):  
Camilla Reis Augusto da Silva ◽  
Marcelo Dos Santos Silva ◽  
Léa Maria Dos Santos Lopes Ferreira ◽  
Kelly Regina Batista Leite ◽  
Lazaro Benedito da Silva

The basis of differentiation between sun and shade leaves is related to different light intensities. In order to understand the adaptability of the leaves of Rhizophora mangle L., associated with different lighting conditions, leaves were collected from the upper peripheral six individuals (sun leaves) and the lower region of the same internal (shade leaves). The variables analyzed leaf thickness, palisade parenchyma, adaxial and abaxial epidermis, adaxial and abaxial cuticle, stomatal density and index. Measurements were made ??on microscope equipped with ocular micrometer. Sun leaves were lower and with more xeromorphic characteristics, such as increased thickness of the cuticle and the adaxial and abaxial epidermis. The palisade parenchyma and limbus showed up thicker than shade leaves, with no significant difference between the cuticle of the abaxial surface. It was also observed a higher frequency of stomata per mm², an average of 70/mm², while shade leaves showed 47/mm², with no differences between length and width. Differences between the sun leaves and shade leaves indicate adaptive capacity of this species to remain active at different light conditions.


Author(s):  
Daiana Jungbluth ◽  
Ana Regina Dahlem Ziech ◽  
Camila Roberta Pereira ◽  
Márcia Cristina Dos Santos ◽  
Patrick Machado

The no-till system has been growing over the years and for this system to be successful, it is essential to maintain permanent vegetation cover over the soil, an adequate crop rotation system with minimal overturning. A strategy for soil protection is to introduce species of cover crops in winter under single or intercropping. The objective was to evaluate the rate of soil cover by intercropping between black oats (Avena strigosa L.) and forage turnip (Raphanus sativus L.) at different sowing densities, as well as the isolated species in terms of soil protection under no-tillage. The study was conducted at the Federal Technological University of Paraná (UTFPR), campus Santa Helena, with a randomized block design, with five treatments and three repetitions. The treatments were: 100% black oats (BO); 100% forage turnip (FT); 75% BO + 25% FT; 50% BO + 50% FT and 25% BO + 75% FT. The cover crops were sown in May 2019. The percentage of soil cover from 21 to 91 days after sowing (DAS) was evaluated using the photographic method, with weekly collection of images in an area delimited by a metallic frame (25 m²), positioned on the ground at two fixed points per plot. The coverage rate quantification was estimated by overlaying a grid with 100 points of intersection over each image. The rate of soil cover by consortia and single crops did not show a statistically significant difference. To 49 days, consortia had coverage equal to or greater than 70%, while for single species, this percentage was reached at 56 DAS and 70 DAS, for BO and FT, respectively. All treatments showed high potential for soil protection and coverage rate from 70 DAS.


Author(s):  
Royan Diana ◽  
Hedijanti Joenoes ◽  
Ariadna A Djais

Objective: This study aimed to compare the effect of Curcuma xanthrorrhiza ethanol extract to the viability of Streptococcus mutans and Aggregatibacter  actinomycetemcomitans using single- and dual-species biofilm at different phases of formation.Methods: Biofilm models were incubated for 4, 12, and 24 hrs, then exposed to the extract at a concentration of 0.525%.Results: The viability of the single-species S. mutans biofilm was low (p<0.05), and no significant difference (p>0.05) was found between singlespeciesA. actinomycetemcomitans and dual-species biofilm.Conclusions: Curcuma xanthorrhiza ethanol extract is more effective for decreasing the viability of single-species S. mutans biofilm.


Author(s):  
L. U. Onyia ◽  
I. J. Ochokwu ◽  
I. J. Bargudu

Monoculture is the rearing of single species of fish in a pond while polyculture is the farming of two or more species in the same physical space. This study aims to compare the growth parameters of Clarias gariepinus fingerlings in monoculture and polyculture, using concrete and earthen ponds in a randomized complete block design. The polyculture, comprised of Clarias gariepinus and Oreochromis niloticus. 480 fingerlings were used; the stocking density was 40fish in a 3x2x1.5m depth with initial weight (4.84±0.11547) for C. gariepinus in monoculture and 40 each in polyculture with an initial pooled weight of O. niloticus (50g) replicated thrice, it was fed for eight weeks with commercial feed (40% crude protein). Weekly, random sampling was done to measure the growth and adjust the feeding rate. The results revealed that polyculture has the best mean final weight (160.07±0.18559g) and weight gain of 155.29, while the highest total length (45.666±3.179) was recorded in monoculture for Clarias gariepinus reared in an earthen pond. The polyculture had the highest specific growth rate (2.46), Relative growth rate (246.49), and condition factor (0.184). There was a significant difference (P<0.05) in monoculture of both concrete and earthen ponds.


Author(s):  
Ruth Callaway ◽  
Simon Jennings ◽  
John Lancaster ◽  
John Cotter

This study aimed to identify the effects of different sieve mesh-sizes on processing time, the number of species retained, diversity measures and multivariate community analysis in the North Sea. Samples were collected at 63 sites throughout the North Sea and washed through two successive sieves, 10-mm and 5-mm mesh respectively.  Processing time for whole samples (5- and 10-mm fraction) averaged 91± 25 min compared with 55±16 min for the 10-mm mesh fraction. Altogether 40% of free-living species and 9% of attached species were recorded exclusively in the 5-mm fraction. The majority of these species were rare. Spatial gradients of species diversity and community structure were identical, independent of the mesh-size used. Multivariate community analysis showed no significant difference between descriptions of community structure based on fauna from 10-mm or 5-mm mesh.  The use of coarser sieving mesh would save time and money, if the aims of an epibenthic survey were to describe broad patterns of community structure and relative diversity. It would be possible to process approximately 50% more samples, if the time saved with 10-mm mesh were allocated to additional sampling. However, if information on single species is required, then sorting with the finer sieve mesh will yield crucial information. It was decided to employ a 5-mm mesh for epibenthic monitoring of the North Sea.


2015 ◽  
Vol 2015 ◽  
pp. 1-9
Author(s):  
Towanou Houètchégnon ◽  
Dossou Seblodo Judes Charlemagne Gbèmavo ◽  
Christine Ajokè Ifètayo Nougbodé Ouinsavi ◽  
Nestor Sokpon

The structural characterization ofProsopis africanaof Benin was studied on the basis of forest inventory conducted in three different vegetation types (savannah, fallow, and field) and three climate zones. The data collected in 139 plots of 1000 m2each related to the diameter at breast (1.3 m above ground), total height, identification, and measurement of DBH relatedP. africanaspecies height. Tree-ring parameters such as Blackman and Green indices, basal area, average diameter, height of Lorey, and density were calculated and interpreted. Dendrometric settings of vegetation type and climate zone (Guinea, Sudan-Guinea, and Sudan) were compared through analysis of variance (ANOVA). There is a significant difference in dendrometric settings according to the type of vegetation and climate zone. Basal area, density, and average diameter are, respectively, 4.47 m2/ha, 34.95 stems/ha, and 37.02 cm in the fields; 3.01 m2/ha, 34.74 stems/ha, and 33.66 cm in fallows; 3.31 m2/ha, 52.39 stems/ha, and 29.61 cm in the savannahs. The diameter distribution and height observed at the theoretical Weibull distribution show that the diameter and height of the populations of the species are present in all positively skewed distributions or asymmetric left, a characteristic of single-species stands with predominance of young individuals or small diameters or heights.


1964 ◽  
Vol 44 (1) ◽  
pp. 89-95 ◽  
Author(s):  
F. D. H. Macdowall

The relative tensile strength of tobacco leaf lamina was estimated from simple measurements of the breaking load and the partially compressed thickness, and used to indicate the effects of various conditions on the tensile strength of the material. The relative strength of cured, Canadian flue-cured tobacco leaves ranged from 100 to 1000 p.s.i. cross section. Thin lamina, found in the basal part of the leaf blade and in the lower leaves on the plant, was strongest. The distribution of pectic substances did not explain this difference within a leaf blade. These observations, and an apparent influence of stomatal orientation on the strength of lamina, suggested an important role of the epidermis in the cohesion of lamina. The partial stomatal alignment, particularly in the lower epidermis, is presumed to have resulted from mechanical stresses exerted by adjoining tissues during growth. A significant difference was indicated between the relative strengths of lamina from two cultivars of tobacco.


1985 ◽  
Vol 231 (1) ◽  
pp. 89-95 ◽  
Author(s):  
S Intrator ◽  
J Elion ◽  
M Thomasset ◽  
A Brehier

The cholecalcins are intracellular vitamin D-dependent calcium-binding proteins. High concentrations of 28 kDa cholecalcins have been found in the kidneys and cerebella of birds and mammals. However, whereas the synthesis of the renal protein is vitamin D-dependent, that of the cholecalcin in the cerebella of young growing chicks and rats is apparently not. In the present study a range of immunological, physicochemical and structural characteristics of renal and cerebellar cholecalcins isolated from a single species, the rat, has been examined to ascertain what, if any, differences there are between them, other than the vitamin D-dependence. Both proteins behaved in exactly the same way during purification and showed complete immunocross-reactivity in Ouchterlony double immunodiffusion and radioimmunoassay. No difference could be detected between them on electrophoresis under denaturing conditions or on two-dimensional isoelectric focusing/electrophoresis. Their amino acid compositions were very similar, as were their u.v.-absorption spectra and their chymotryptic and tryptic peptide maps. The N-terminal sequence was found to be Gly-Gly-Val-Ser... for both cholecalcins. We have thus been unable to show any significant difference between the two proteins and suggest that the 28 kDa cholecalcins of the rat cerebellum and kidney are extremely similar, if not identical.


2018 ◽  
Vol 131 (4) ◽  
pp. 369-371
Author(s):  
Bill Thompson

Bald Eagles (Haliaeetus leucocephalus) and Great Blue Herons (Ardea herodias) are known to occasionally nest in mixed colonies, even though the former is one of the primary predators of the latter. I observed the two species in four heron colonies near Lake Simcoe, Ontario during two field seasons to assess whether rates of heron chick mortality or nest abandonment were greater in a colony that supported a nesting pair of Bald Eagles than in three nearby single-species colonies. I assessed the effects of eagle presence on heron behaviour using heron movement rates, the number of heron sentries left in colonies during the nesting period, heron nest mortality rates, and the average number of successfully fledged herons per nest. There was no statistically significant difference in movement rate among the four colonies, proportion of birds remaining as sentries, nor nest mortality rates. However, nests in the mixed colony successfully fledged significantly more heron young per nest than did nests in the single-species colonies. The mixed colony was located in a wetland and open lake system that provided extensive foraging habitat and an abundance of the preferred fish prey species of both Great Blue Herons and Bald Eagles, thus reducing predation pressure on the herons.


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