The pattern of vascular deployment near the pulvinus of the solar-tracking leaf of Lavatera cretica (Malvaceae)

1987 ◽  
Vol 65 (10) ◽  
pp. 2109-2117 ◽  
Author(s):  
F. J. F. Fisher ◽  
D. L. Ehret ◽  
J. Hollingdale
Keyword(s):  
Outer Cylinder ◽  
Vascular Pattern ◽  
First Order ◽  
Flexible Tube ◽  
Solar Tracking ◽  
Tracking Movements ◽  
Lateral Branches ◽  
Subsequent Splitting ◽  
Coaxial Tube

Distinguishable files of xylem and phloem elements that originate in first-order branches of the seven palmate major veins of Lavatera cretica leaves become separated from files unique to the radially aligned sections of the same veins before entering the pulvinus at the distal end of the petiole. The major veins initially merge to form a double coaxial tube: the outer cylinder comprises files unique to the major veins and the inner cylinder comprises files from lateral branches. Subsequent splitting, unfolding, and recombining of these cylinders results in the single narrow flexible tube constituting the hinge of the pulvinus. Proximal to this point, in L. cretica, the files reseparate into six alternately large and small petiolar bundles. The observed vascular pattern offers a means whereby signals from the lamina that elicit sun-tracking movements by the pulvinus can be integrated.

Panicle, spikelet, and floret development in orchardgrass (Dactylis glomerata)

1993 ◽  
Vol 71 (4) ◽  
pp. 523-532 ◽  
Author(s):  
Joanna Fraser ◽  
Eric G. Kokko
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Unique Feature ◽  
Dactylis Glomerata ◽  
Bilateral Symmetry ◽  
Second Order ◽  
Third Order ◽  
First Order ◽  
Lateral Branches ◽  
Scanning Electron

The initial stages of panicle, spikelet, and floret development in field-grown 'Kay' orchardgrass were examined using scanning electron microscopy. Spikelets arose from a complex multilevelled sequence of initiation from branch apices. Spikelets developed indirectly in a two-tiered progression: (i) an acropetal and basipetal sequence of first order, second-order, and third-order inflorescence apices, and (ii) an acropetal development within subclusters of higher-order lateral branch inflorescence apices. The panicle had the unique feature of dorsiventrality as well as bilateral symmetry. The basal apex from first-order, second-order, or third-order apices developed on the same side of the main axis as the first-order apex. The two glumes subtending each spikelet primordium developed alternately and acropetally. Development and initiation of florets within spikelets was basipetal within the panicle, basipetal within clusters and subclusters of spikelets on lateral branches, and acropetal within spikelets. Within florets, paleas developed later than lemmas. Key words: Dactylis glomerata, cocksfoot, scanning electron microscopy, development, panicle.

scholarly journals Growth of Scots pine plus trees clones, selected by resin productivity in Nizhny Novgorod region

2021 ◽  
Vol 25 (4) ◽  
pp. 5-14
Author(s):  
N.N. Besschetnova ◽  
◽  
V.P. Besschetnov ◽  
A.N. Gorelov ◽  
◽  
...  
Keyword(s):  
Scots Pine ◽  
First Order ◽  
Plus Tree ◽  
Growing Conditions ◽  
Lateral Branches ◽  
Clonal Composition ◽  
Degree Of Similarity ◽  
Nizhny Novgorod Region

The taxational indicators of clones of plus trees of Scots pine, selected by resin productivity, were studied in comparison with similar characteristics of plants, selected by linear parameters of the trunk. They are represented They are presented in the assortment of the forest seed plantation No. 10 in the Semenovsky forestry of the Nizhny Novgorod region, created in 1984 on a plot with the type of forest growing conditions — B2, and the type of forest — maynikovo-lingonberry pine. In the organization of the work, the principle of the only logical difference was observed, as well as the requirements for the typicality, suitability and expediency of the experience. As a test marker for checking the purity of the clonal composition of the plantation, the value of the angle of attachment of the first-order lateral branches to the trunk was used. The height and diameter of the trunk are taken into account in 571 trees with a continuous list. The distribution of the average values of the analyzed indicators in the vegetative offspring of plus trees compared with each other is not uniform. The highest height (16,70 ± 0,43 m) observed in clones of the K-011 plus tree selected by resin productivity is 2,65 m or 1,19 times higher than the lowest value (14,05 ± 0,44 m) inherent in clones of the K-113 plus tree selected by the same criteria, and 2,02 m or 1,14 times higher than the lowest value (14,23 ± 0,31 m) inherent in clones of the K-171 plus tree selected by the same criteria taxational indicators of the trunk. Differences in the taxational indicators of clones in the group of plus trees distinguished by resin productivity, as well as in the group of trunks distinguished by characteristics, correspond to the level of significant ones, which indicates the specificity of their genotypes. The degree of similarity of the plus trees in terms of trunk parameters is not the same, which indicates a different level of individual non-identity of each of the plus trees in relation to the others in their considered population.

Light quality and sun tracking in Malva neglecta

1989 ◽  
Vol 67 (2) ◽  
pp. 515-520 ◽  
Author(s):  
F J. F. Fisher ◽  
D. L. Ehret ◽  
G. R. Lister ◽  
J. Hollingdale
Keyword(s):  
Active Component ◽  
Light Quality ◽  
Light Treatment ◽  
Spectral Quality ◽  
Solar Tracking ◽  
Spectral Components ◽  
Additional Radiation ◽  
Direction Of Movement ◽  
Quantum Flux ◽  
Tracking Movements

Two distinct spectral components were found to be necessary to produce solar-tracking movements of the leaves of Malva neglecta: a small blue vectorial component with a quantum flux as low as 10 μmol∙m−2∙s−1 was found to be sufficient to determine the direction of movement, but responses do not take place unless additional radiation (regardless of spectral quality or direction) raise the total photosynthetically active component above the current light compensation point (70 μmol∙m−2∙s−1). This additional radiation could be given simultaneously or in an immediately preceding light treatment.

Melvillipteris quadriseriatagen. et sp. nov., a new plant assigned to Rhacophytales from the Upper Devonian (Famennian) of Arctic Canada

2015 ◽  
Vol 153 (4) ◽  
pp. 601-617 ◽  
Author(s):  
JIN-ZHUANG XUE ◽  
JAMES F. BASINGER
Keyword(s):  
Adventitious Roots ◽  
Canadian Arctic ◽  
Second Order ◽  
Upper Devonian ◽  
Late Devonian ◽  
Canadian Arctic Archipelago ◽  
Branching Pattern ◽  
First Order ◽  
Branching System ◽  
Lateral Branches

AbstractA new plant of Late Devonian (Famennian) age,Melvillipteris quadriseriatagen. et sp. nov., is reported from Melville Island, Nunavut, Canadian Arctic Archipelago. Main axes and two orders of lateral branches are recognized. The main axes are monopodial in habit, with a zigzag and/or upright appearance and dense adventitious roots attached on some internodes. First-order branches are inserted on the main axes in distichous pairs, showing a quadriseriate pattern (i.e. alternate pairs); they bear one or two sterile ultimate appendages on the proximal portions, and then distally bear alternate second-order branches. Second-order branches bear alternate ultimate appendages which may be fertile or sterile; the sterile ultimate appendages are composed of one or two successive dichotomies, terminating in oppositely recurved tips, and fertile appendages show an elaborate branching system. Each fertile appendage has an initial dichotomy forming two sister branches, each of which further divides three or four times to produce ultimate divisions terminated by sporangia. Two to four small fusiform sporangia are grouped in a truss which is supplied by penultimate division of the fertile appendage. The sporangia have a pointed tip and a longitudinal dehiscence. This new plant resembles other plants with a quadriseriate branching pattern (e.g.RhacophytonCrépin,CephalopterisNathorst,ProtocephalopterisAnaniev,EllesmerisHill, Scheckler & Basinger andProtopteridophytonLi & Hsü), and is assigned to the Rhacophytales. Its similarity to and divergence from the rhacophytaleans, cladoxylopsids and other related plants are discussed.

scholarly journals GENETIC DYNAMICS OF CONIFEROUS INTRODUCENTS IN THE CONDITIONS OF A FOOTHILL DESERT-STEPPE ZONE IN THE SOUTH OF KAZAKHSTAN

2017 ◽  
Vol 5 ◽  
pp. 1204-1209
Author(s):  
Dani N. Sarsekova
Keyword(s):  
Steppe Zone ◽  
Desert Steppe ◽  
The South ◽  
First Order ◽  
Pine Trees ◽  
The Mean ◽  
Yellow Pine ◽  
The Republic ◽  
Genetic And Environmental Factors ◽  
Lateral Branches

Forest breeding should be produced not only by the representatives of the local flora, which is not very diverse in some areas of the Republic of Kazakhstan, but by species and forms of trees growing in temperate zones of the worldwide. In particular, this refers to arboretums located in the conditions significantly different from the place of natural growth of the introduced species. One of this arboretum is the JSC "Forest nursery" of the Ministry of Science and Higher Education of the Republic of Kazakhstan which is located in the South-East of the republic.The aim of this study was to study the ecological and genetic variability of coniferous introducents in the foothill desert-steppe zone and to determine the share of genetic and environmental factors. The variability and the relative stability of the expression of the quantitative trait in ontogenesis, which characterizes the species adaptation to the new conditions in 9 Yellow pine trunks, Crimean pine trunks and Scots pine trees, 7 Blue spruce trees and the same number of trees in European spruce, in which annual increments of the height of one morphological Location.Beginning with the growth of 2014 and then sequentially down the trunk, so long as lateral branches of the first order in whorls were preserved or traces were observed in a good way. Thus, the value of the mean squares differs significantly in the increments of a single morphological location and in the increments of tree groups, in the introductions species and in the periods of their life. Therefore we are allowed to conclude that there are still some parts and interference in the estimation of the ecological, genotypic and phenotypic dispersions that have different values and are manifested to a greater extent, or in the analysis of increments of tree groups, or increments of one morphological location, that is, they change the cause of their display.

The nervous system of Loligo , III. Higher motor centres: the basal supraoesophageal lobes

1977 ◽  
Vol 276 (948) ◽  
pp. 351-398 ◽  
Keyword(s):  
Functional Organization ◽  
Tracking System ◽  
Efference Copy ◽  
Small Cells ◽  
Similar System ◽  
Optic Lobes ◽  
First Order ◽  
Basal Lobe ◽  
Parallel Fibres ◽  
Tracking Movements

The three main basal lobes are orientated in different planes set approximately at right angles. The components of each are similar and based on an organization reminiscent of a cerebellum, like that of the peduncle lobes. They all have large cells and fibres ventrally and numerous small cells dorsally. Each of the two parts of the anterior basal lobe contains a region with numerous very fine parallel fibres, similar to the ‘spine’ of the peduncle lobes. The dorsal basal lobes contain a similar system, but less regular. The three main parts of the basal lobe system all send fibres to the oculomotor centres of the lateral pedal lobes. The two parts of the anterior basal lobe also send fibres to the centres controlling arm movements in the anterior pedal lobe. The median basal lobe sends large tracts to the posterior pedal lobe, controlling movement of the funnel and fins. It also sends a large tract to the region of the first order giant cell, initiating the jet. There is a further massive system of descending fibres from all the basal lobes (and the precommissural lobe) sending branches to all parts of the magnocellular and palliovisceral lobes. The functional organization of the basal and peduncle lobes can be understood as follows. They all receive visual and static inputs and send large outputs to the oculomotor centre and back to the optic lobes. The oculomotor centre also receives direct inputs from the statocyst. The control of eye movements is thus organized in cephalopods in the same way as it is in vertebrates: there is a direct static input to the oculomotor centre, which also receives indirect static influences combined with visual ones, by way of the cerebellum in vertebrates, or basal and peduncle lobes in cephalopods. The basal and peduncle lobes show further similarity to the cerebellum in the presence of the numerous parallel fibres of various diameters, some very fine. These lobes receive dorsal and ventral sets of visual fibres and a set from the magnocellular lobes. The dorsal visual fibres follow the topology of the optic lobes and it is suggested that they provide a tracking system. The numerous fibres passing back from the basal lobes to the optic lobes, allow for a ‘corollary discharge’ (‘efference copy’). The ventral set of large fibres from the optic lobes to the basal lobes may serve to promote the final attack, after the smaller fibres have produced the preliminary tracking movements. The system of large fibres from the magnocellular to the basal lobes are perhaps concerned with avoiding reactions. Each of the large fibres of both of these sets gives branches to all parts of the basal lobes. All the basal lobes contain many microneurons with trunks limited to the lobes. Some of these are very short amacrines. The median basal and dorsal basal lobes contain especially numerous small cells, perhaps neurosecretory and related to reproduction by way of the optic gland, whose nerve arises nearby.

Trial-by-Trial Updating of the Gain in Preparation for Smooth Pursuit Eye Movement Based on Past Experience in Humans

2008 ◽  
Vol 99 (2) ◽  
pp. 747-758 ◽  
Author(s):  
Hiromitsu Tabata ◽  
Kenichiro Miura ◽  
Kenji Kawano
Keyword(s):  
Smooth Pursuit ◽  
Environmental Changes ◽  
Preceding Trial ◽  
Smooth Pursuit Eye Movements ◽  
First Order ◽  
Pursuit Eye Movements ◽  
The Past ◽  
History Of ◽  
Tracking Movements ◽  
Past Experiences

To understand how the CNS uses past experiences to generate movements that accommodate minute-by-minute environmental changes, we studied the trial-by-trial updating of the gain for initiating smooth pursuit eye movements and how this relates to the history of previous trials. Ocular responses in humans elicited by a small perturbing motion presented 300 ms after appearance of a target were used as a measure of the gain of visuomotor transmission. After the perturbation, the target was either moved horizontally (pursuit trial) or remained in a stationary position (fixation trial). The trial sequence randomly included pursuit and fixation. The amplitude of the response to the perturbation was modulated in a trial-by-trial manner based on the immediately preceding trial, with preceding fixation and pursuit trials decreasing and increasing the gain, respectively. The effect of the previous trial was larger with shorter intertrial intervals, but did not diminish for at least 2,000 ms. A time-series analysis showed that the response amplitude was significantly correlated with the past few trials, with dynamics that could be approximated by a first-order linear system. The results suggest that the CNS integrates recent experiences to set the gain in preparation for upcoming tracking movements in a changing environment.

The architectural significance of interfoliar branches in Pinus subsection Balfourianae

1987 ◽  
Vol 17 (3) ◽  
pp. 269-272 ◽  
Author(s):  
Kristina F. Connor ◽  
Ronald M. Lanner
Keyword(s):  
Great Basin ◽  
Rocky Mountain ◽  
Second Order ◽  
Morphological Data ◽  
First Order ◽  
Bristlecone Pine ◽  
Foxtail Pine ◽  
Architectural Significance ◽  
Lateral Branches

In pines, branches of interfoliar origin (IFBs) often occur in response to injury. However, in all three species of Pinus subsection Balfourianae we observed in Utah, Nevada, and California, IFBs are common and of nontraumatic origin. They comprise 41 and 51% of the first-order branches in foxtail pine (Pinusbalfouriana Grev. & Balf.) and Great Basin bristlecone pine (P. longaeva D. K. Bailey), respectively. Second-order IFBs are frequent in Rocky Mountain bristlecone pine (P. aristata Engelm.) (45%) and Great Basin bristlecone pine (47%). All species of subsection Balfourianae produce exceptionally low numbers of long-shoot lateral branches (LSLBs). Growth and morphological data suggest that the IFBs function similarly to LSLBs.

Dual systems for all: Higher-order, role-based relational reasoning as a uniquely derived feature of human cognition

2019 ◽  
Vol 42 ◽  
Author(s):  
Daniel J. Povinelli ◽  
Gabrielle C. Glorioso ◽  
Shannon L. Kuznar ◽  
Mateja Pavlic
Keyword(s):  
Temporal Reasoning ◽  
Higher Order ◽  
Important Case ◽  
Human Cognition ◽  
Relational Reasoning ◽  
Dual Systems ◽  
First Order ◽  
Reasoning System ◽  
Role Based

Abstract Hoerl and McCormack demonstrate that although animals possess a sophisticated temporal updating system, there is no evidence that they also possess a temporal reasoning system. This important case study is directly related to the broader claim that although animals are manifestly capable of first-order (perceptually-based) relational reasoning, they lack the capacity for higher-order, role-based relational reasoning. We argue this distinction applies to all domains of cognition.

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