STUDIES ON THE RHIZOSPHERE MICROFLORA OF CITRUS TREES: I. QUANTITATIVE INCIDENCE OF MICROORGANISMS IN RELATION TO ROOT AND SHOOT GROWTH

1962 ◽  
Vol 8 (4) ◽  
pp. 473-477 ◽  
Author(s):  
G. Rangaswami ◽  
V. N. Vasantharajan
Keyword(s):  
Shoot Growth ◽  
The Other ◽  
Citrus Species ◽  
Fungal Population ◽  
Rhizosphere Microflora ◽  
Significant Difference ◽  
Root And Shoot Growth ◽  
Rhizosphere Population ◽  
Species Comparisons ◽  
Citrus Variety

For the purpose of examining the correlations, if any, between the root and shoot growths of three Citrus species and their rhizosphere microflora, studies were made with 6-year-old plants in the Annamalai University Experimental Orchard. The rhizosphere population was analyzed quantitatively. Bacteria were about 40 to 90 times, actinomycetes 2 to 6 times, and fungi 3 to 6 times more abundant in the rhizosphere than in the soil, in rhizosphere populations there was no significant difference between the three Citrus species. Comparisons of populations on the growing and non-growing roots of the three Citrus species revealed that the growing roots harbored 2 to 3 times more bacteria and actinomycetes than the non-growing roots. There was only slight increase in the fungal population in the rhizosphere of the citrus variety Pummelo but not in the other two varieties.

scholarly journals Species and Their Relationships with Air and Soil Temperatures

1999 ◽  
Vol 9 (1) ◽  
pp. 131
Author(s):  
Timothy K. Broschat
Keyword(s):  
Root Growth ◽  
Growth Rates ◽  
Shoot Growth ◽  
Cocos Nucifera ◽  
Primary Root ◽  
The Other ◽  
Date Palms ◽  
Primary Roots ◽  
Root And Shoot Growth ◽  
Soil Temperatures

Royal palms [Roystonea regia (HBK.) O.F. Cook], coconut palms (Cocos nucifera L. `Malayan Dwarf'), queen palms [Syagrus romanzoffiana (Chamisso) Glassman], and pygmy date palms (Phoenix roebelenii O'Brien) were grown in a rhizotron to determine the patterns of root and shoot growth over a 2-year period. Roots and shoots of all four species of palms grew throughout the year, but both root and shoot growth rates were positively correlated with air and soil temperature for all but the pygmy date palms. Growth of primary roots in all four species was finite for these juvenile palms and lasted for only 5 weeks in royal palms, but ≈7 weeks in the other three species. Elongation of secondary roots lasted for only 9 weeks for coconut palms and less than half of that time for the other three species. Primary root growth rate varied from 16 mm·week-1 for coconut and pygmy date palms to 31 mm·week-1 for royal palms, while secondary root growth rates were close to 10 mm·week-1 for all species. About 25% of the total number of primary roots in these palms grew in contact with the rhizotron window, allowing the prediction of the total root number and length from the sample of roots visible in the rhizotron. Results indicated that there is no obvious season when palms should not be transplanted in southern Florida because of root inactivity.

Effect of BAS-145–138 on the phytotoxicity of imazaquin and metsulfuron-methyl

Weed Science ◽  
1999 ◽  
Vol 47 (2) ◽  
pp. 130-135
Author(s):  
Alain Seguin ◽  
Henri Milhomme ◽  
Norbert M. Satchivi
Keyword(s):  
Shoot Growth ◽  
The Other ◽  
Growth Chamber ◽  
Corn Root ◽  
Metsulfuron Methyl ◽  
Herbicide Safener ◽  
Root And Shoot Growth ◽  
Low Levels

The influence of the experimental herbicide safener BAS-145–138 on the toxicity of imazaquin and metsulfuron-methyl was investigated in two corn varieties in growth chamber bioassays. BAS-145–138 alone slightly decreased root and shoot growth but this decrease was not dependent on the safener concentration. The imbibition of seeds of both corn varieties with low levels of safener caused substantially less damage in the roots and shoots especially with the highest metsulfuron-methyl doses used in the study. In one variety, the safener significantly increased corn root tolerance to imazaquin and to metsulfuron-methyl 1.5- and 2.3-fold, respectively; the concentrations of both herbicides producing 50% inhibition were higher for safened seedlings. In the other variety, a high antidotal influence of BAS-145–138 imbibition on metsulfuron-methyl was observed in shoot growth.

scholarly journals Exploring Aluminum Tolerance at Seedling Stage in Rice (Oryza sativa, Linn) by Using Modified Magnavaca Nutrient Solution

2017 ◽  
Vol 23 (2) ◽  
pp. 81
Author(s):  
Nurul Hidayatun ◽  
Maria Genaleen Q. Diaz ◽  
Abdelbaghi M. Ismail
Keyword(s):  
Crop Production ◽  
Shoot Growth ◽  
Al Toxicity ◽  
Shoot Length ◽  
Root Weight ◽  
Rice Varieties ◽  
Al Stress ◽  
Significant Difference ◽  
Root And Shoot Growth ◽  
Relative Root

<p>Aluminum (Al) toxicity is considered as one of the main constraints for crop production in acidic soil. This study was subjected to observe the response of root and shoot growth of eight rice varieties under Al stress in hydrophonic solution. A modified Magnavaca’s solution was used to compare the effect of Al stress using different variables which were relative root elongation (RRE), relative shoot length (RSL) and relative root weight (RRW). The experiment was conducted in split-plot experimental design. Eight rice varieties were screened in four Al levels (0 μM, 540 μM, 750 μM, and 1,300 μM). Root length, shoot length,<br />and root dry weight were measured after 7 days of treatment, then the RRE, RSL, and RRW were calculated. The results showed that Al significantly reduced RRE and RSL but increased RRW. RSL was reduced as the Al concentration increased while RRE reduction started only at 750 μM Al concentration. It was observed that RRW was significantly higher under 540 and 750 μM Al concentration. However, no significant difference was observed in 1,300 μM Al concentration. The increase in root weight is partly attributed by the thickening of the root wall, but this effect was diminished due to root hair inhibition under 1,300 μM Al concentration. Among these three variables observed, root and shoot lengths indicated better variables in determining Al tolerance in rice, compared to root weight. However, these variables were not sufficient to represent root and shoot growth inhibition, and not sufficient to be used solely for Al toxicity screening</p>

scholarly journals Root and Shoot Growth Patterns in Four Palm Species and Their Relationships with Air and Soil Temperatures

HortScience ◽  
1998 ◽  
Vol 33 (6) ◽  
pp. 995-998 ◽  
Author(s):  
Timothy K. Broschat
Keyword(s):  
Root Growth ◽  
Growth Rates ◽  
Shoot Growth ◽  
Cocos Nucifera ◽  
Growth Patterns ◽  
The Other ◽  
Date Palms ◽  
Primary Roots ◽  
Palm Species ◽  
Root And Shoot Growth

Royal palms [Roystonea regia (HBK.) O.F. Cook], coconut palms (Cocos nucifera L. `Malayan Dwarf'), queen palms [Syagrus romanzoffiana (Chamisso) Glassman], and pygmy date palms (Phoenix roebelenii O'Brien) were grown in a rhizotron to determine the patterns of root and shoot growth over a 2-year period. Roots and shoots of all four species of palms grew throughout the year, but both root and shoot growth rates were positively correlated with air and soil temperature for all but the pygmy date palms. Growth of primary roots in all four species was finite for these juvenile palms and lasted for only 5 weeks in royal palms, but ≈7 weeks in the other three species. Elongation of secondary roots lasted for only 9 weeks for coconut palms and less than half of that time for the other three species. Primary root growth rate varied from 16 mm·week-1 for coconut and pygmy date palms to 31 mm·week-1 for royal palms, while secondary root growth rates were close to 10 mm·week-1 for all species. About 25% of the total number of primary roots in these palms grew in contact with the rhizotron window, allowing the prediction of the total root number and length from the sample of roots visible in the rhizotron. Results indicated that there is no obvious season when palms should not be transplanted in southern Florida because of root inactivity.

scholarly journals 356 ROOT AND SHOOT GROWTH PERIODICITY OF GREEN ASH, SCARLET OAK, TURKISH HAZELNUT AND TREE LILAC

HortScience ◽  
1994 ◽  
Vol 29 (5) ◽  
pp. 482a-482
Author(s):  
J. Roger Harris ◽  
Nina L. Bassuk ◽  
Richard W. Zobel ◽  
Thomas H. Whitlow
Keyword(s):  
Root Growth ◽  
Shoot Growth ◽  
Growth Patterns ◽  
The Other ◽  
Extension Rate ◽  
Green Ash ◽  
Extension Method ◽  
Root Extension ◽  
Root And Shoot Growth ◽  
Growth Periodicity

Root and shoot growth periodicity were determined for Fraxinus pennsylvanica Marsh. (green ash), Quercus coccinea Muenchh.,Corylus colurna L. (Turkish hazehut) and Syriaga reticulara (Blume) Hara `Ivory Silk' (tree lilac) trees. Two methods for determining root growth periodicity using a rhizotron were evaluated. One method measured the extension rate of individual roots, and the second method measured change in root length density. A third method, using periodic counts of new roots present on minirhizotrons, was also evaluated. The root extension method showed the least variability among individual trees. Shoot growth began before or simultaneously with the beginning of root growth for all species with all root growth measurement methods. Species with similar shoot phenologies had similar root phenologies when root growth was measured by the root extension method, but not when root growth was measured by the other methods. All species had concurrent shoot and root growth, and no distinct alternating growth patterns were evident when root growth was measured with the root extension method. Alternating root and shoot growth was evident, however, when root growth was measured by the other methods.

scholarly journals Growth and Protein Content of Apple in Response to Root and Shoot Temperature following Chilling

HortScience ◽  
1990 ◽  
Vol 25 (12) ◽  
pp. 1583-1588 ◽  
Author(s):  
Michael A. Arnold ◽  
Eric Young
Keyword(s):  
Shoot Growth ◽  
Adventitious Shoots ◽  
The Other ◽  
Growth Enhancement ◽  
Root Bark ◽  
Protein Breakdown ◽  
Growth Responses ◽  
Protein Levels ◽  
Root And Shoot Growth ◽  
Lower Protein

Bare-root Malus × domestica Borkh. seedlings were chilled for 0, 600, 1200, or 1800 hours at 5C (CH). Seedlings were then placed with roots and/or shoots in all combinations of 5 and 20C forcing conditions (FC) for up to 21 days. Virtually no growth occurred at 5C FC. When the whole plant was forced at 20C, all measures of root and shoot growth increased in magnitude, occurred earlier and at a faster rate with increasing CH. Thus, roots and shoots responded similarly to chilling. When shoots or roots were subjected to 20C FC, while the other portion of the plant was at 5C, the responses were reduced in magnitude and delayed. However, the overall growth enhancement by chilling was not negated. Root and shoot growth enhancement by chilling appeared to be increased if the other portion of the plant was actively growing also, but not dependent on it. Growth of adventitious shoots on roots (root suckers) was greatly enhanced with increasing CH on plants subjected to 5C shoot and 20C root FC. While total root and shoot bark protein levels on a per-seedling basis were similar, protein concentrations were lower in root bark than in shoot bark. During chilling, total protein per seedling generally increased until just before the time that chilling requirements for vegetative budbreak were satisfied. Protein degradation then began, resulting in lower protein levels through 2300 CH. Rapid protein breakdown (1200 to 1800 CH, roots; 1000 to 1800 CH, shoots) occurred at about the same time that root (1000 to 1800 CH) and shoot (800 to 1800 CH) growth responses to chilling were increasing. Warm FC resulted in increased protein breakdown with increased CH and forcing time.

Effects of waterlogging, rootstock and salinity on Na, Cl and K concentrations of the leaf and root, and shoot growth of sultana grapevines

1995 ◽  
Vol 46 (3) ◽  
pp. 541 ◽  
Author(s):  
RM Stevens ◽  
G Harvey
Keyword(s):  
Vitis Vinifera ◽  
Shoot Growth ◽  
Potassium Concentration ◽  
Chloride Concentration ◽  
The Other ◽  
Vitis Vinifera L ◽  
Root And Shoot Growth

Potted Sultana vines ( Vitis vinifera L. cv. Sultana) on own-roots or grafted onto Ramsey, Harmony, Schwarzmann or 1613 rootstocks were irrigated with solutions containing 1, 10, 20, 40 or 60 mM NaCl. Half the vines had free-draining rootzones and the other half were waterlogged for the first week in a 2-week cycle. The vines were harvested after seven cycles. Raising the irrigation salinity from 1 to 60 mM caused growth to decline by 47% in vines with free-draining rootzones and by 61% in vines with waterlogged rootzones. Under saline conditions, the use of chloride excluding rootstock reduced leaf chloride concentration by 60% in vines with free-draining rootzones but by only 18% in vines with waterlogged rootzones. Waterlogging decreased the root chloride concentration in all rootstocks. The leaf potassium concentration was reduced by waterlogging at irrigation salinities less than 20 mM NaCl and increased by waterlogging at higher salinities. Waterlogging altered the relative effects of rootstock on leaf potassium.

Writing in Aphasia Rehabilitation: Cursive vs Manuscript

1976 ◽  
Vol 41 (4) ◽  
pp. 523-529 ◽  
Author(s):  
Daniel R. Boone ◽  
Harold M. Friedman
Keyword(s):  
Correct Response ◽  
The Other ◽  
Read Aloud ◽  
Writing Style ◽  
Reading And Writing ◽  
Manual Responses ◽  
Significant Difference ◽  
Written Form ◽  
The Individual ◽  
Read Number

Reading and writing performance was observed in 30 adult aphasic patients to determine whether there was a significant difference when stimuli and manual responses were varied in the written form: cursive versus manuscript. Patients were asked to read aloud 10 words written cursively and 10 words written in manuscript form. They were then asked to write on dictation 10 word responses using cursive writing and 10 words using manuscript writing. Number of words correctly read, number of words correctly written, and number of letters correctly written in the proper sequence were tallied for both cursive and manuscript writing tasks for each patient. Results indicated no significant difference in correct response between cursive and manuscript writing style for these aphasic patients as a group; however, it was noted that individual patients varied widely in their success using one writing form over the other. It appeared that since neither writing form showed better facilitation of performance, the writing style used should be determined according to the individual patient’s own preference and best performance.

Multi-Center Study of Thromboplastin Calibration Precision – Influence of Reagent Species, Composition, and International Sensitivity Index (ISI)

1993 ◽  
Vol 69 (01) ◽  
pp. 035-040 ◽  
Author(s):  
A M H P van den Besselaar ◽  
R M Bertina
Keyword(s):  
Oral Anticoagulants ◽  
International Normalized Ratio ◽  
The Other ◽  
World Health ◽  
Rabbit Brain ◽  
Sensitivity Index ◽  
Bovine Plasma ◽  
Significant Difference ◽  
The Mean ◽  
International Sensitivity Index

SummaryFour thromboplastin reagents were tested by 18 laboratories in Europe, North-America, and Australasia, according to a detailed protocol. One thromboplastin was the International Reference Preparation for ox brain thromboplastin combined with adsorbed bovine plasma (coded OBT/79), and the second was a certified reference material for rabbit brain thromboplastin, plain (coded CRM 149R). The other two thromboplastin reagents were another rabbit plain brain thromboplastin (RP) with a lower ISI than CRM 149R and a rabbit brain thromboplastin combined with adsorbed bovine plasma (RC). Calibration of the latter two reagents was performed according to methods recommended by the World Health Organization (W. H. O.).The purpose of this study was to answer the following questions: 1) Is the calibration of the RC reagent more precise against the bovine/combined (OBT/79) than against the rabbit/plain reagent (CRM 149R)? 2) Is the precision of calibration influenced by the magnitude of the International Sensitivity Index (ISI)?The lowest inter-laboratory variation of ISI was observed in the calibration of the rabbit/plain reagent (RP) against the other rabbit/plain reagent (CRM 149R) (CV 1.6%). The highest interlaboratory variation was obtained in the calibration of rabbit/plain (RP) against bovine/combined (OBT/79) (CV 5.1%). In the calibration of the rabbit/combined (RC) reagent, there was no difference in precision between OBT/79 (CV 4.3%) and CRM 149R (CV 4.2%). Furthermore, there was no significant difference in the precision of the ISI of RC obtained with CRM 149R (ISI = 1.343) and the rabbit/plain (RP) reagent with ISI = 1.14. In conclusion, the calibration of RC could be performed with similar precision with either OBT/79 or CRM 149R, or RP.The mean ISI values calculated with OBT/79 and CRM 149R were practically identical, indicating that there is no bias in the ISI of these reference preparations and that these reference preparations have been stable since their original calibration studies in 1979 and 1987, respectively.International Normalized Ratio (INR) equivalents were calculated for a lyophilized control plasma derived from patients treated with oral anticoagulants. There were small but significant differences in the mean INR equivalents between the bovine and rabbit thromboplastins. There were no differences in the interlaboratory variation of the INR equivalents, when the four thromboplastins were compared.

IMMUNOLOGICAL REACTIVITY OF INSULIN IN HUMAN SERUM

1966 ◽  
Vol 53 (4) ◽  
pp. 673-680 ◽  
Author(s):  
Torsten Deckert ◽  
Kai R. Jorgensen
Keyword(s):  
Normal Subjects ◽  
The Other ◽  
Human Pancreas ◽  
Porcine Pancreas ◽  
Crystalline Insulin ◽  
Endogenous Insulin ◽  
Significant Difference ◽  
Human Sera ◽  
Normal Human ◽  
The One

ABSTRACT The purpose of this study was to investigate whether a difference could be demonstrated between crystalline insulin extracted from normal human pancreas, and crystalline insulin extracted from bovine and porcine pancreas. Using Hales & Randle's (1963) immunoassay no immunological differences could be demonstrated between human and pig insulin. On the other hand, a significant difference was found, between pig and ox insulin. An attempt was also made to determine whether an immunological difference could be demonstrated between crystalline pig insulin and crystalline human insulin from non diabetic subjects on the one hand and endogenous, circulating insulin from normal subjects, obese subjects and diabetic subjects on the other. No such difference was found. From these experiments it is concluded that endogenous insulin in normal, obese and diabetic human sera is immunologically identical with human, crystalline insulin from non diabetic subjects and crystalline pig insulin.

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