scholarly journals Preliminary estimation of physiological activity of 9-amine-9-fluorenephosphonic acid derivatives

2013 ◽  
Vol 34 (2) ◽  
pp. 253-260 ◽  
Author(s):  
W. Czerwiński ◽  
R. Gancarz ◽  
E. Przybyłka ◽  
J. S. Wieczorek

The physiological activity of twenty one 9-amine-9-fluorenephosphonic acid derivatives was tested. The compounds were synthesized by the Wrocław Technical University. <i>Spirodela oligorrhiza</i> was used as the test plant. There was tested the inhibiting influence of these compounds on the growth of <i>Spirodela</i> and synergism with the herbicide "mecoprop". Ethyl esters substituted at the nitrogen atom with buthyl and heptyl group appeared to be most active. Their concentration of 0.5-1.5 × 10<sup>-5</sup> M inhibited the growth of <i>Spirodela</i> by 50%. Most of the 9-amine-9-fluorenephosphonic acid derivatives tested with different substitutes showed a strong synergism with the herbicide "mecoprop". An addition of these compounds to sublethal solution of the herbicide killed <i>Spirodela</i> within 10-20 houres.

2013 ◽  
Vol 40 (1-2) ◽  
pp. 53-57 ◽  
Author(s):  
Henryk Skrabka ◽  
Elżbieta Jaskulska

The physiological activity of eleven 9-amine-9-fluorenephosphonic acid derivatives, synthesized at the Wrocław Polytechnic, was examined. The test plant was <i>Spirodela oligorrhiza</i>. The effect of these compounds on the increase of the dry matter of this plant was tested in eight-day experiments. The activity of the compounds was varied. The most toxic were nos. 2, 4, 9, 8, 5 and 6 which were lethal in low concentrations. Somewhat less toxic were nos. 7, 10 and 11; nos. 1 and 3 were the least toxic.


2001 ◽  
Vol 56 (11-12) ◽  
pp. 995-998 ◽  
Author(s):  
Krzysztof Bielecki ◽  
Anna Dziamska ◽  
Janusz Sarapuk

Abstract Influence of some new am inophosphonates on electrolyte leakage from cucumber (Cucu­-mis sativus cv "Wisconsin") cotyledons as well as on the content of chlorophyll and activity of guaiacol and pyrogallol peroxidase were studied. Concentration of malondialdehyde (MDA), one of the end-products of lipid peroxidation, was also measured. It was found that am inophosphates influenced the parameters observed to various extents, depending on their structural features and the concentration used. Most active modifiers were those possessing sufficiently long hydrocarbon substituents at the nitrogen atom and/ or iso-propyl chain at the phosphorus atom.


Author(s):  
H. D. Geissinge ◽  
L.D. Rhodes

A recently discovered mouse model (‘mdx’) for muscular dystrophy in man may be of considerable interest, since the disease in ‘mdx’ mice is inherited by the same mode of inheritance (X-linked) as the human Duchenne (DMD) muscular dystrophy. Unlike DMD, which results in a situation in which the continual muscle destruction cannot keep up with abortive regenerative attempts of the musculature, and the sufferers of the disease die early, the disease in ‘mdx’ mice appears to be transient, and the mice do not die as a result of it. In fact, it has been reported that the severely damaged Tibialis anterior (TA) muscles of ‘mdx’ mice seem to display exceptionally good regenerative powers at 4-6 weeks, so much so, that these muscles are able to regenerate spontaneously up to their previous levels of physiological activity.


EDIS ◽  
2017 ◽  
Vol 2017 (5) ◽  
Author(s):  
Davie Mayeso Kadyampakeni ◽  
Kelly T. Morgan ◽  
Mongi Zekri ◽  
Rhuanito Ferrarezi ◽  
Arnold Schumann ◽  
...  

Water is a limiting factor in Florida citrus production during the majority of the year because of the low water holding capacity of sandy soils resulting from low clay and the non-uniform distribution of the rainfall. In Florida, the major portion of rainfall comes in June through September. However, rainfall is scarce during the dry period from February through May, which coincides with the critical stages of bloom, leaf expansion, fruit set, and fruit enlargement. Irrigation is practiced to provide water when rainfall is not sufficient or timely to meet water needs. Proper irrigation scheduling is the application of water to crops only when needed and only in the amounts needed; that is, determining when to irrigate and how much water to apply. With proper irrigation scheduling, yield will not be limited by water stress. With citrus greening (HLB), irrigation scheduling is becoming more important and critical and growers cannot afford water stress or water excess. Any degree of water stress or imbalance can produce a deleterious change in physiological activity of growth and production of citrus trees.  The number of fruit, fruit size, and tree canopy are reduced and premature fruit drop is increased with water stress.  Extension growth in shoots and roots and leaf expansion are all negatively impacted by water stress. Other benefits of proper irrigation scheduling include reduced loss of nutrients from leaching as a result of excess water applications and reduced pollution of groundwater or surface waters from the leaching of nutrients. Recent studies have shown that for HLB-affected trees, irrigation frequency should increase and irrigation amounts should decrease to minimize water stress from drought stress or water excess, while ensuring optimal water availability in the rootzone at all times.


Author(s):  
P.B. Teh

AMV was shown to be transmitted by sap, aphids and through lucerne seed, but not by Cuscuta. Virus source and test plant influenced transmission frequency. Sap-inoculation tests showed that 20 species of plants were susceptible to this virus. Thirteen species of plants from the fields where AMV had been detected were tested but only three were found to be infected with the virus.


Fitoterapia ◽  
2019 ◽  
Vol 2 (2) ◽  
pp. 57-58
Author(s):  
I. V. Pushchina ◽  
◽  
J. A. Maliarenko ◽  
A. A. Kovalova ◽  
O. V. Kovalova ◽  
...  

Author(s):  
Alexander G. Okhapkin ◽  
Tabet Hhedairia

The preliminary estimation of composition and structure of diatoms in the benthos of the Oka River allowed to determine the clear spatiotemporal confinedness of structure in such communities of them which has the most diverse composition in the low water period while water temperature decreasing.


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