Mycorrhizal Conifer Roots From the Lower Cretaceous of the Otway Basin, Victoria

1988 ◽  
Vol 36 (3) ◽  
pp. 257 ◽  
Author(s):  
DJ Cantrill ◽  
JG Douglas
Keyword(s):  
Lower Cretaceous ◽  
Phosphate Uptake ◽  
Lateral Roots ◽  
General Morphology ◽  
Plant Associations ◽  
Mycorrhizal Association ◽  
Mycorrhizal Roots ◽  
Poor Soil ◽  
Channel Deposit

Fossil roots with nodular and abbreviated lateral roots are described from the Devils Kitchen locality within the Lower Cretaceous Otway Group. The general morphology of these roots indicates a mycorrhizal association, the oldest such record from Australia. Based on the root morphology and associated megaflora it is considered that the roots are coniferous (Taxodiaceae or Podocarpaceae); an association of the roots with foliage of Geinitzia tetragona sp. nov., which is possibly taxodiaceous, is indicated. The major role of nodular mycorrhizal roots in extant plants is phosphate uptake which enhances minor nitrogen uptake. It is suggested that the fossil roots may have had a similar role. The Devils Kitchen locality is interpreted as a levee or near channel deposit with better drainage andlor a nutrient-poor soil relative to other soils in the sequence. The atypical plant associations of Cladophlebis australis, C. sp. b, and Geinitzia tetragona sp. nov. are a reflection of the above.

scholarly journals Myco-Suppression Analysis of Soybean (Glycine max) Damping-Off Caused by Pythium aphanidermatum

Plants ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 788
Author(s):  
Shaban R. M. Sayed ◽  
Shaimaa A. M. Abdelmohsen ◽  
Hani M. A. Abdelzaher ◽  
Mohammed A. Elnaghy ◽  
Ashraf A. Mostafa ◽  
...  
Keyword(s):  
Glycine Max ◽  
Biocontrol Agent ◽  
Lateral Roots ◽  
Dry Weight ◽  
Pythium Aphanidermatum ◽  
Damping Off ◽  
Pythium Oligandrum ◽  
Rdna Its ◽  
Half Strength

The role of Pythium oligandrum as a biocontrol agent against Pythium aphanidermatum was investigated to avoid the harmful impacts of fungicides. Three isolates of P. oligandrum (MS15, MS19, and MS31) were assessed facing the plant pathogenic P. aphanidermatum the causal agent of Glycine max damping-off. The tested Pythium species were recognized according to their cultural and microscopic characterizations. The identification was confirmed through sequencing of rDNA-ITS regions including the 5.8 S rDNA. The biocontrol agent, P. oligandrum, isolates decreased the mycelial growth of the pathogenic P. aphanidermatum with 71.3%, 67.1%, and 68.7% through mycoparasitism on CMA plates. While the half-strength millipore sterilized filtrates of P. oligandrum isolates degrade the pathogenic mycelial linear growth by 34.1%, 32.5%, and 31.7%, and reduce the mycelial dry weight of the pathogenic P. aphanidermatum by 40.1%, 37.4%, and 36.8%, respectively. Scanning electron microscopy (SEM) of the most effective antagonistic P. oligandrum isolate (MS15) interaction showed coiling, haustorial parts of P. oligandrum to P. aphanidermatum hyphae. Furthermore, P. oligandrum isolates were proven to enhance the germination of Glycine max seedling to 93.3% in damping-off infection using agar pots and promote germination of up to 80% during soil pot assay. On the other hand, P. oligandrum isolates increase the shoot, root lengths, and the number of lateral roots.

scholarly journals Trace fossils, sedimentary facies and parasequence architecture from the Lower Cretaceous Mulichinco Formation of Argentina: The role of fair-weather waves in shoreface deposits

2018 ◽  
Vol 367 ◽  
pp. 146-163 ◽  
Author(s):  
Lindsey J.N. Wesolowski ◽  
Luis A. Buatois ◽  
M. Gabriela Mángano ◽  
Juan José Ponce ◽  
Noelia B. Carmona
Keyword(s):  
Lower Cretaceous ◽  
Sedimentary Facies ◽  
Trace Fossils ◽  
Fair Weather

Role of mature leaves in inhibition of root bud growth inEuphorbia esulaL.

Weed Science ◽  
1999 ◽  
Vol 47 (5) ◽  
pp. 544-550 ◽  
Author(s):  
David P. Horvath
Keyword(s):  
Lateral Roots ◽  
Axillary Buds ◽  
Minor Effect ◽  
Correlative Inhibition ◽  
Auxin Transport Inhibitor ◽  
Naphthylphthalamic Acid ◽  
Bud Growth ◽  
A Minor ◽  
Root Buds

Earlier studies on the source of signals controlling correlative inhibition of root buds (underground adventitious buds located on the lateral roots) inEuphorbia esulaindicated that either growing meristems (apical or axillary buds) or fully expanded leaves could prevent root buds from breaking quiescence. An investigation of the production and transport requirements of the leaf-derived signal is described. As few as three leaves remaining on budless stems greatly reduced the growth of (but not the number of growing) root buds. Also, light and CO2fixation were necessary for the leaf effects on root bud growth, but not necessary for correlative inhibition imposed by growing axillary buds. Treatment of plants with Ametryn induced root bud growth on budless plants but not on plants with intact axillary buds. The polar auxin transport inhibitor N-1-naphthylphthalamic acid prevented transmission or the signal from growing axillary buds, but it had only a minor effect on the transmission of the leaf-derived signal. Treatment of plants with gibberellic acid (GA) induced growth of root buds under otherwise noninducing conditions to some extent in all plants. However, the greatest effects of GA were on plants with intact leaves (meristemless/budless and meristemless). GA had no significant effect on root bud quiescence under conditions that induced root bud growth.

scholarly journals Screening Different Divalent and Trivalent Metals Containing Binary and Ternary Layered Double Hydroxides for Optimum Phosphate Uptake

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Sattam Fahad Almojil ◽  
Mohamed Abdelhalim Othman
Keyword(s):  
Layered Double Hydroxides ◽  
Phosphate Uptake ◽  
Synergistic Effects ◽  
Bet Surface Area ◽  
Primary Role ◽  
Specific Element ◽  
Phosphate Ion ◽  
Sorbent Materials ◽  
Double Hydroxides

Abstract The elements constituting a layered double hydroxides material provide many alternatives for its optimization. Ten different layered double hydroxides materials with various combinations of Ni, Cu, Zn, Al, Cr, and Fe elements were studied as sorbent materials for phosphate ion. The type of element used in the layered double hydroxides affected the uptake capacity of phosphate. The influence of a specific element alone was not the primary role of enhancing the sorption performance of phosphate ion on the LDHs material. However, using specific two or three elements together is the key to achieve the best result due to synergistic effects. BET surface area of the sorbent showed no correlation with phosphate uptake. From the examined materials, Four layered double hydroxides of Cu-Zn-Cr, Zn-Cr, Ni-Al, and Cu-Ni-Cr showed high phosphate sorption capability. Sorption equilibrium isotherm, reaction kinetics, and desorption of phosphate from the sorbent materials were also investigated.

scholarly journals Raymond Charles Casey. 10 October 1917—26 April 2016

2020 ◽  
Vol 68 ◽  
pp. 71-86 ◽  
Author(s):  
Peter F. Rawson ◽  
Adrian W. A. Rushton ◽  
Martin I. Simpson
Keyword(s):  
Great Britain ◽  
Soviet Union ◽  
Lower Cretaceous ◽  
Geological Survey ◽  
Time Service ◽  
Similar Role ◽  
Home Town ◽  
The Soviet Union ◽  
Spare Time

Raymond Casey was an internationally recognized expert in two entirely different fields—geology and philately. He achieved this despite leaving school at 14. By then he was already collecting and studying fossils from his home town, Folkestone, and in 1939, despite not having a degree, he obtained a post with the Geological Survey of Great Britain in the modest role of assistant to C. J. Stubblefield. After war-time service in the RAF, he returned to the Survey in a similar role, but spent much of his ‘spare time’ researching and publishing on Lower Cretaceous palaeontology and stratigraphy. His fortunes began to change when, at the age of 38, he was admitted to Reading University to study for a doctorate. His thesis on Lower Greensand stratigraphy and palaeontology was recognized as an outstanding study that led to major publications including a nine-part monograph of the ammonite faunas. Then, in the late 1950s, he also began to study faunas from Jurassic–Cretaceous boundary beds in eastern England as part of his official work and this led to him visiting the Soviet Union on several occasions from 1963 onward. On the first visit he met the academician Nalivkin in Leningrad, who, as well as being an eminent geologist, was a keen philatelist. This led to Raymond taking an enthusiastic interest in pre-revolutionary Russian postal history, which resulted in numerous publications and awards and, after his retirement, became his main focus of interest.

Establishment and growth of shoots following low and high cutting of lucerne in relation to the pattern of nutrient uptake

1973 ◽  
Vol 24 (4) ◽  
pp. 497 ◽  
Author(s):  
KC Hodgkinson
Keyword(s):  
Phosphorus Content ◽  
Lateral Roots ◽  
Nitrogen And Phosphorus ◽  
Relative Growth ◽  
Relative Growth Rates ◽  
Tap Root ◽  
Cutting Frequency ◽  
Net Uptake ◽  
High Level

Lucerne plants (Medicogo sativa cv. Hunter River) were either frequently or infrequently cut down and subsequent differences in shoot regrowth were compared in two experiments. The first experiment demonstrated that differences in final shoot weights arose from differences developed during the first 7 days of regrowth. High level cutting (15 cm) increased the shoot yield of frequently but not of infrequently cut plants. Net uptake of both nitrogen and phosphorus was related to the growth rate of shoots until commencement of flowering, when uptake ceased for c. 15 days even though both roots and shoots continued to gain weight. Towards the end of flowering uptake of nitrogen and phosphorus recommenced and accumulation of both nutrients occurred in the tap-root and lateral roots. The relative nitrogen and phosphorus content of leaves on crown shoots was highest on day 7 and the same for frequently and infrequently cut plants. Leaves on crown and stubble shoots 7 days after high level cutting had a significantly lower relative nitrogen and phosphorus content than leaves on plants cut low. Thereafter the relative nitrogen and phosphorus content of a11 leaves declined with the greatest decline occurring after the commencement of flowering. In the second experiment early morphogenesis of the shoot population was investigated. Establishment of shoots was completed between 3 and 5 days after cutting. Higher shoot weights on infrequently cut plants were accounted for by a larger number of small shoots at the time of cutting. Relative growth rates of shoots did not appear to be influenced by prior cutting frequency. The relative nitrogen content of buds and shoot apices was low at cutting but doubled within 2 or 3 days and then declined after day 7. These results are discussed in relation to the role of 'plant factors' in shoot regrowth of lucerne.

Role of auxins and cytokinins in the development of lateral roots in wheat plants with several roots removed

2007 ◽  
Vol 54 (3) ◽  
pp. 402-406 ◽  
Author(s):  
L. B. Vysotskaya ◽  
A. V. Cherkoz’yanova ◽  
S. Yu. Veselov ◽  
G. R. Kudoyarova
Keyword(s):  
Lateral Roots

Role of Alkaline Phosphatase in Phosphate Uptake into Brush Border Membrane Vesicles from Human Intestinal Mucosa

1985 ◽  
Vol 97 (5) ◽  
pp. 1461-1466 ◽  
Author(s):  
Kazuyuki HIRANO ◽  
Yuichi IIIZUMI ◽  
Yukio MORI ◽  
Kazumi TOYOSHI ◽  
Mamoru SUGIURA ◽  
...  
Keyword(s):  
Alkaline Phosphatase ◽  
Intestinal Mucosa ◽  
Brush Border ◽  
Brush Border Membrane ◽  
Phosphate Uptake ◽  
Membrane Vesicles ◽  
Brush Border Membrane Vesicles

Illusion and reality in comparative physiology

1981 ◽  
Vol 59 (11) ◽  
pp. 2151-2158 ◽  
Author(s):  
D. M. Ross
Keyword(s):  
Dominant Role ◽  
Special Theory ◽  
Physiological Adaptation ◽  
Conceptual Level ◽  
Comparative Physiology ◽  
Experimental Zoology ◽  
General Morphology ◽  
History Of ◽  
General Explanation

The dominant role of comparative physiology (syn. experimental zoology) in the recent history of animal biology is noted. Its objectives, e.g. of contributing to knowledge of phylogenetic relationships and of discovering the origins of physiological functions, are considered to have been largely illusory when the data are examined. It is argued that in reality comparative physiology is concerned only with the description of adaptations, albeit at a sophisticated technical and conceptual level compared with natural history or general morphology. Comparative physiology has not produced any special theory or general explanation for physiological adaptation going beyond Darwin's general theory of natural selection.

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