STUDIES ON THE CYTOGENETIC AND GENETIC EFFECTS OF FLUORIDE ON BARLEY.: I. A COMPARATIVE STUDY OF THE EFFECTS OF SODIUM FLUORIDE AND HYDROFLUORIC ACID ON SEEDLING ROOT TIPS

1973 ◽  
Vol 15 (4) ◽  
pp. 695-702 ◽  
Author(s):  
S. S. Bale ◽  
G. E. Hart
Keyword(s):  
Comparative Study ◽  
Seedling Growth ◽  
Sodium Fluoride ◽  
Chromosomal Aberrations ◽  
Hydrofluoric Acid ◽  
Root Tips ◽  
Fluoride Ions ◽  
Binucleate Cells ◽  
Seedling Root ◽  
Inhibition Of Growth

The effects of sodium fluoride and hydrofluoric acid on barley were determined and compared following treatments of seedling root tips at three different concentrations (1 × 10−2M, 1 × 10−4M, 1 × 10−6M) and for six different durations (12, 24, 36, 48, 60, and 72 hr). Treatment with a 1 × 10−2M concentration of either sodium fluoride or hydrofluoric acid markedly slowed the rate of seedling growth. However, no inhibition of growth was observed following treatment with a 1 × −4M or a 1 × 10−6M concentration of either agent. Chromosomal aberrations were induced and mitosis was inhibited by each of the three different concentrations of both sodium fluoride and hydrofluoric acid. The sodium fluoride treatments induced a higher frequency of chromosomal aberrations than did the hydrofluoric acid treatments, possibly due to differences in pH and in the total available fluoride ions. These treatments produced bridges, fragments, chromosome gaps, binucleate cells and micronuclei.

Variation in field response of Pinussylvestris to nursery inoculation with four different ectomycorrhizal fungi

1990 ◽  
Vol 20 (11) ◽  
pp. 1796-1803 ◽  
Author(s):  
Elna Stenström ◽  
Mats Ek ◽  
Torgny Unestam
Keyword(s):  
Growth Rate ◽  
Seedling Growth ◽  
Ectomycorrhizal Fungi ◽  
Relative Difference ◽  
Forest Species ◽  
Root Tips ◽  
Inhibition Of Growth ◽  
Field Response ◽  
Nursery Production ◽  
Indigenous Forest

Pinussylvestris L. seedlings were inoculated in nursery containers with the assertive mycorrhizal formers Laccarialaccata (Scop, ex Fr.) Bk. & Br., Hebelomacrustuliniforme (Bull, ex Fr.) Quélet, and Cenococcumgeophilum Fr. After outplanting, seedling size and the frequency of mycorrhizal root tips were monitored over 6 years. Between 25 and 90% of the root tips of inoculated seedlings were mycorrhizal with the target fungi at outplanting, whereas the noninoculated control seedlings were spontaneously colonized by other fungi at rates between 25 and 50%. After 1.5 years the inoculated fungi were still present on the roots; however, they were slowly being replaced by indigenous forest species. In the nursery, most of the inoculations resulted in reduced seedling growth. This inhibition of growth rate was pronounced up to 1.5 years in the field, except for seedlings inoculated with C. geophilum. By this time, L. laccata and H. crustuliniforme inoculated seedlings were about 40 to 50% smaller in volume than the control seedlings, and the relative difference in size was maintained or slightly decreased during the following 4 years. The noninoculated nursery production seedlings were about 50% larger in volume than the corresponding control seedlings at outplanting. In the field, however, they grew relatively slower and consequently, were soon similar in volume to the control seedlings.

Development of Douglas-fir seedling root architecture in response to localized nutrient supply

2003 ◽  
Vol 33 (1) ◽  
pp. 118-125 ◽  
Author(s):  
Douglass F Jacobs ◽  
Robin Rose ◽  
Diane L Haase
Keyword(s):  
Seedling Growth ◽  
Nutrient Release ◽  
Douglas Fir ◽  
Root Penetration ◽  
Root Tips ◽  
Seedling Root ◽  
Application Rates ◽  
Soil Osmotic Potential ◽  
Photochemical Quantum Yield ◽  
High Application

Three months following sowing, Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) seedlings were transplanted into pots with controlled-release fertilizer (CRF) applied at rates of 0, 8, 16, and 24 g/2200 cm3 soil as a single uniform layer beneath the root system. Seedlings were destructively harvested periodically, and roots were divided into vertical segments above (S1), within (S2), and below (S3) the fertilizer layer. Two months following transplant, the number of active root tips was positively correlated with CRF rate in S1 and negatively correlated with rate in S2 and S3. At 6 months, root penetration into S3 was severely restricted at 16 and 24 g. This was attributed to detrimental changes in soil osmotic potential in S2. Fertilizer improved seedling growth at 8 g after 6 months compared with controls but was inhibitory at 24 g. Photochemical quantum yield was higher in all CRF treatments compared with controls 3 months following transplant, which corresponded with rapid initial CRF nutrient release. Despite improvements in nutrient release technology with CRF, high application rates may result in excessive concentrations of fertilizer nutrients in media, which can restrict root penetration and negatively affect seedling growth. Conservative application rates and improvements in CRF technology will help reduce the potential for adverse effects on seedling development.

Critical care management of hydrofluoric acid burns with a negative outcome

2021 ◽  
Vol 14 (6) ◽  
pp. e242187
Author(s):  
Aalekh Prasad ◽  
Heba Ibrahim ◽  
Katherine Mortimore ◽  
Rohan Vandabona
Keyword(s):  
Hydrofluoric Acid ◽  
Care Management ◽  
Vital Role ◽  
Severe Metabolic Acidosis ◽  
Fluoride Ions ◽  
Subcutaneous Injections ◽  
Electrolyte Disturbances ◽  
Severe Burns ◽  
Systemic Reactions ◽  
Critical Care Management

Hydrofluoric acid is a highly corrosive acid widely used in various industries. When in contact with skin it causes local and systemic reactions due to the generation of fluoride ions. Severe burns are associated with high mortality rates, approaching 100%. We present a 21-year-old man with 15% full thickness burns, severe metabolic acidosis, hypoxia and electrolyte disturbances. The burns were treated with topical and subcutaneous injections of calcium gluconate, and the patient was given intravenous fluid, calcium chloride, magnesium and insulin-glucose infusions. Continuous renal replacement therapy was initiated due to the severity of the systemic toxicity. Extracorporeal membrane oxygenation was considered as it plays a vital role when conventional therapies fail. Our patient suffered multiple cardiac arrests and cardiopulmonary resuscitation was conducted several times but despite extensive efforts, he did not survive.

Fluoride Ions Concentration in Saliva and Urine after Ingestion of Sodium Fluoride Tablet in Hostel Inmates of Dental College

2013 ◽  
Vol 4 (3) ◽  
pp. 9-11
Author(s):  
Omprakash Yadav ◽  
Apurv Soni ◽  
Ashok K Mohapatra ◽  
Chirag Tandon ◽  
Pankaj Choudhary ◽  
...  
Keyword(s):  
Sodium Fluoride ◽  
Fluoride Ions

Vapour phase catalytic transformations of terpene hydrocarbons in the C10H16 series. III. Dehydrogenation of Δ3-carene over modified chromia and chromia–alumina catalysts

1976 ◽  
Vol 54 (21) ◽  
pp. 3458-3463 ◽  
Author(s):  
V. Krishnasamy ◽  
L. M. Yeddanapalli
Keyword(s):  
Hydrofluoric Acid ◽  
Vapour Phase ◽  
Potassium Ions ◽  
Total Conversion ◽  
Fluoride Ions ◽  
Catalytic Transformations ◽  
Alumina Catalysts

The vapour phase dehydrogenation of 3-carene has been studied over chromia, chromia–alumina, chromia doped with potassium, and chromia–alumina doped with potassium and fluoride ions. Addition of potassium to chromia and chromia–alumina up to 1% by weight does not significantly affect the overall conversion of 3-carene whereas it increases its dehydrogenation to p- and m-cymenes. Potassium ions above 1% lower both the total conversion and dehydrogenation of 3-carene to cymenes. The ratio of p- to m-cymene over chromia–alumina is enhanced by added potassium ions up to 2%, but over chromia it remains unaffected. Addition of potassium to chromia decreases the formation of menthanes and menthadienes but its addition to chromia–alumina reduces the formation of menthanes and increases that of menthadienes. Impregnation of chromia–alumina with hydrofluoric acid suppresses the formation of menthadienes and increases that of menthanes. All these are explained in terms of the effect of added potassium and fluoride ions on the acidity of the catalysts.

The effect of Cylindrocarpon destructans on the growth of Eucalyptus regnans seedlings in air-dried and undried forest soil

2010 ◽  
Vol 58 (2) ◽  
pp. 133 ◽  
Author(s):  
T. M. Iles ◽  
D. H. Ashton ◽  
K. J. Kelliher ◽  
P. J. Keane
Keyword(s):  
Root Growth ◽  
Forest Soil ◽  
Seedling Growth ◽  
Frequency Of Occurrence ◽  
Root Tips ◽  
Eucalyptus Regnans ◽  
Cylindrocarpon Destructans ◽  
Pot Experiments ◽  
Growth Of Seedlings

The growth of Eucalyptus regnans F.Muell. (mountain ash) seedlings is poor in natural forest soil, where purple coloration of the foliage indicates P deficiency and where the fungus Cylindrocarpon destructans (Zinsm.) Scholten is commonly isolated from the roots of the seedlings. When forest soil is air-dried, P acquisiton and growth of seedlings are markedly improved, although the degree of growth stimulation varies considerably at different times, as does the frequency of occurrence of C. destructans on the roots. C. destructans has been implicated as a possible reason for suppressed growth of seedlings in undried natural soil. To find out whether C. destructans contributes to growth inhibition of E. regnans seedlings in undried forest soil, the effect of three isolates of C. destructans on the root growth of E. regnans seedlings was tested in Petri dish experiments in vitro and the effect of C. destructans inoculation on seedling growth both in air-dried and undried forest soil was tested in pot experiments. The frequency of occurrence of C. destructans on the roots varied at different times, and was not consistently higher in undried than in air-dried soil, even though the growth of the seedlings was always poor in undried soil compared with that in air-dried soil. In vitro, C. destructans decreased the root growth significantly and caused blackening of root tips. This effect was removed by adding natural air-dried or undried soil. In pot experiments using undried forest soil, there was no evidence of either direct toxic effect or any other adverse effect on the roots when soil was inoculated with this fungus, even when the growth of the seedlings was reduced to ~1/2 of that in uninoculated undried soil. In air-dried soil, inoculation with the fungus did not significantly reduce seedling growth. Although potentially pathogenic and able to cause blackening of root tips, C. destructans is unlikely to be the main reason for poor seedling growth in undried forest soil. It appears to be antagonistic rather than pathogenic, suppressing seedling growth only under unfavourable conditions, such as in undried soil, possibly by competing for limited nutrients, or by suppressing other beneficial micro-organisms. The results are discussed in the context of field conditions.

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