A Short-Term Bioassay for Whole Plant Toxicity

2009 ◽  
pp. 355-355-10 ◽  
Author(s):  
T Pfleeger ◽  
C Mc Farlane ◽  
R Sherman ◽  
G Volk
Keyword(s):  
Short Term ◽  
Plant Toxicity ◽  
Whole Plant

Whole-Plant Responses to Salinity

1986 ◽  
Vol 13 (1) ◽  
pp. 143 ◽  
Author(s):  
R Munns ◽  
A Termaat
Keyword(s):  
Root Growth ◽  
Leaf Growth ◽  
Water Status ◽  
Leaf Expansion ◽  
Saline Soils ◽  
Plant Responses ◽  
Short Term ◽  
Whole Plant ◽  
Short Term Exposure

This paper discusses whole-plant responses to salinity in order to answer the question of what process limits growth of non-halophytes in saline soils. Leaf growth is more sensitive to salinity than root growth, so we focus on the process or processes that might limit leaf expansion. Effects of short-term exposure (days) are considered separately from long-term exposure (weeks to years). The answer in the short term is probably the water status of the root and we suggest that a message from the root is regulating leaf expansion. The answer to what limits growth in the long term may be the maximum salt concentration tolerated by the fully expanded leaves of the shoot; if the rate of leaf death approaches the rate of new leaf expansion, the photosynthetic area will eventually become too low to support continued growth.

scholarly journals Assimilate distribution in bean plants (Phaseolus vulgaris L.) during phosphate limitation

2014 ◽  
Vol 68 (4) ◽  
pp. 269-273 ◽  
Author(s):  
Iwona Ciereszko ◽  
Irena Miłosek ◽  
Anna M. Rychter
Keyword(s):  
Phaseolus Vulgaris ◽  
Nutrient Medium ◽  
Phosphate Deficiency ◽  
Assimilate Transport ◽  
Phosphate Limitation ◽  
Sugar Accumulation ◽  
Short Term ◽  
Whole Plant ◽  
Bean Plants

The influence of phosphate deficiency on the increased "C-assimilate transport from shoot to root of bean plants (<em>Phaseolus vulgaris</em> L.) was studied. The roots of plants were cultured in split configurations (a half of the root system was exposed to a short-term or long-term culture in phosphate-deficient nutrient medium, while the other half - in complete nutrient medium) to establish the conditions of translocation enhancement. It was found that both short term Pi stress applied to a part of root and longer localized phosphate deficiency is not sufficient to increase assimilate transport from the shoot to the root. Low concentration of Pi in tissues of the whole plant as a signal for changes in assimilate distribution and sugar accumulation in the roots is discussed.

scholarly journals (142) Hydraulic Resistance: A Determinant of Short-term Stomatal Conductance Signaling in Disparate Xylem Anatomy of Red Maple (Acer rubrum L.) and Shumard Oak (Quercus shumardii Buckl.)

HortScience ◽  
2006 ◽  
Vol 41 (4) ◽  
pp. 1058A-1058
Author(s):  
William W. Inman ◽  
William L. Bauerle
Keyword(s):  
Stomatal Conductance ◽  
Hydraulic Resistance ◽  
Acer Rubrum ◽  
Net Photosynthesis ◽  
Xylem Anatomy ◽  
Red Maple ◽  
Short Term ◽  
Whole Plant ◽  
Substrate Moisture ◽  
Quercus Shumardii

Recent work has shown that stomatal conductance (gs) and net photosynthesis (Anet) are responsive to the hydraulic conductance of the soil to leaf pathway (Xp). Two tree species with differing xylem structures were used to study the effect of systematic manipulations in Xp that elevated xylem hydraulic resistance. Simultaneous measures of gs, Anet, bulk leaf abscisic acid concentration (ABAL), leaf water potential (L), and whole plant transpiration (Ew) were taken under controlled environment conditions. Quercus shumardii Buckl. (shumard oak), a ring porous species and Acer rubrum L. `Summer Red' (red maple), a diffuse porous species, were studied to investigate the short-term hydraulic and chemical messenger response to drought. Both species decreased Anet, gs, L, and Ew in response to an immediate substrate moisture alteration. Relative to initial well-watered values, red maple Anet, gs, and Ew declined more than shumard oak. However, gs and Anet vs. whole-plant leaf specific hydraulic resistance was greater in shumard oak. In addition, the larger hydraulic resistance in shumard oak was attributed to higher shoot, as opposed to root, system resistance. The results indicate hydraulic resistance differences that may be attributed to the disparate xylem anatomy between the two species. This study also provides evidence to support the short-term hydraulic signal negative feedback link hypothesis between gs and the cavitation threshold, as opposed to chemical signaling via rapid accumulation from root-synthesized ABA.

Mill case, simulation, and laboratory plant study of black liquor spill effects on a multiple stage biological treatment plantA paper submitted to the Journal of Environmental Engineering and Science.

2009 ◽  
Vol 36 (5) ◽  
pp. 839-849 ◽  
Author(s):  
Maria Sandberg
Keyword(s):  
Biological Treatment ◽  
Black Liquor ◽  
Treatment Plant ◽  
Oxygen Demand ◽  
Short Term ◽  
Whole Plant ◽  
Term Trial ◽  
High Concentrations ◽  
Good Relation ◽  
The Impact

In this study, the impact of black liquor shocks on multiple stage biological treatment plant was studied. The tests were carried out in a lab scale plant and using a mathematical simulation model. The results showed good relation to a parallel situation at the Gruvön Mill. The MultiBio concept is persistent to short-term black liquor spills due to the design where the black liquor is diluted between every compartment. According to the lab scale trials, short-term shocks (5 and 10 h) of black liquor addition reduce bio activity in the first part of the MultiBio plant. Oxygen uptake rate and chemical oxygen demand (COD) degradation decreased during high concentrations of black liquor and increased when the black liquor concentration declined. Protozoas disappeared from compartments exposed to high concentrations of black liquor. A long-term trial encompassing 24 h of black liquor addition inhibited the COD reduction in the whole plant for several weeks.

Short-term responses of leaf growth rate to water deficit scale up to whole-plant and crop levels: an integrated modelling approach in maize

2008 ◽  
Vol 31 (3) ◽  
pp. 378-391 ◽  
Author(s):  
KARINE CHENU ◽  
SCOTT C. CHAPMAN ◽  
GRAEME L. HAMMER ◽  
GREG MCLEAN ◽  
HALIM BEN HAJ SALAH ◽  
...  
Keyword(s):  
Growth Rate ◽  
Water Deficit ◽  
Leaf Growth ◽  
Scale Up ◽  
Integrated Modelling ◽  
Short Term ◽  
Whole Plant ◽  
Modelling Approach

scholarly journals Growth and Nutritional Responses of Cowpea (cv. Soronko) to Short-term Elevated Temperature

HortScience ◽  
2020 ◽  
Vol 55 (9) ◽  
pp. 1495-1499
Author(s):  
Thalukanyo Nevhulaudzi ◽  
Khayalethu Ntushelo ◽  
Sheku Alfred Kanu
Keyword(s):  
Elevated Temperature ◽  
Nutritional Quality ◽  
Crude Protein ◽  
Elevated Temperatures ◽  
Growth Stages ◽  
Crude Protein Content ◽  
Short Term ◽  
Whole Plant ◽  
Different Growth Stages

Short-term variations in temperature associated with climate change have been noted to affect the physiological processes and metabolite profile of plants, including the nutritional status, ultimately affecting their growth and development. An evaluation of the effects of elevated temperatures on the growth and nutritional quality of cowpea was performed during this experiment. The main objective was to evaluate the effects of short-term elevated temperatures on the nutritional quality of cowpea at different growth stages. Surface-sterilized seeds of cowpea (cv. Soronko) were germinated in pots in the glasshouse. At different growth stages (preflowering, flowering, and postflowering), plants were incubated in growth chambers set at three different temperature regimes (25, 30, and 35 °C) for a period of 7 days. Compared with control (25 °C), exposure to both elevated temperatures (30 and 35 °C) reduced the whole plant fresh weight and dry weight by 30% and 52% and 42% and 29%, respectively, at the preflowering stage, and by 31 and 60% and 47 and 63%, respectively, at the flowering/anthesis stage. However, no significant difference in whole plant biomass was noted between elevated temperatures (35%) and the control temperature at the postflowering stage. Short-term exposure to an elevated temperature (35 °C) increased the shoot crude protein content (5.59 N%) of cowpea compared with control (3.77 N%) and preflowering stage. In contrast, at the flowering stage, an elevated temperature (35 °C) reduced the crude protein content (1.77%) of the shoot compared with control (5.59%). At an elevated temperature (35 °C), the preflowering and flowering stages of cowpea were most affected compared with control. These results suggest that the preflowering and flowering stages of cowpea compared with the postflowering stage are more susceptible to elevated temperatures (30 to 35 °C).

scholarly journals Influence of Spring and Fall Drought Stresses on Growth and Gas Exchange during Stress and Posttransplant of Container-grown Magnoli ×soulangiana `Jane'

2002 ◽  
Vol 127 (1) ◽  
pp. 38-44 ◽  
Author(s):  
R. Thomas Fernandez ◽  
Robert E. Schutzki ◽  
Kelly J. Prevete
Keyword(s):  
Drought Stress ◽  
Stomatal Conductance ◽  
Gas Exchange ◽  
Leaf Gas Exchange ◽  
Growth Index ◽  
Severe Drought ◽  
Severe Stress ◽  
Flower Number ◽  
Short Term ◽  
Whole Plant

Responses of Magnolia ×soulangiana (Soul.-Bod.) `Jane' (`Jane' saucer magnolia) to consecutive short term pretransplant drought stresses and recovery after transplanting were evaluated beginning October 1997 and June 1998. Plants were subjected to one (mild) or two (moderate) 3-day drought stress periods or a two 3-day and one 4-day (severe) drought stress period, each separated by two rewatering periods over 24 hours. One day after each stress period, plants were transplanted into the field and well watered to monitor recovery from stress. Plant response was determined by measuring whole-plant CO2 assimilation, leaf gas exchange (CO2 assimilation, transpiration, stomatal conductance) and canopy growth throughout stress and recovery periods. Whole-plant and leaf CO2 assimilation were lower for the stressed treatments for most of the measurements taken during stress in the fall and spring. After release from stress and transplanting, leaf CO2 assimilation returned to control levels for mild and moderate fall stresses within 2 to 3 d by the next measurement, while it was over 3 weeks until recovery from the severe stress. There was no difference in leaf gas exchange following release from stress and transplanting during the spring stress. More rapid defoliation occurred for the severe fall-stressed plants compared to the controls after release from stress in the fall. Flower number was reduced in spring for the fall-stressed plants. At termination of the experiment, the growth index was lower for severe fall-stressed plants but there were no differences for other fall stress treatments. There was no increase in growth for control or stressed plants for the spring experiment.

scholarly journals Effects of NaCl-salinity on growth and inorganic solute accumulation in young cashew plants

2001 ◽  
Vol 5 (2) ◽  
pp. 216-222 ◽  
Author(s):  
Ricardo A. Viégas ◽  
Joaquim A. G. da Silveira ◽  
Adeildo R. de Lima Junior ◽  
José E. Queiroz ◽  
Maria J. M. Fausto
Keyword(s):  
Fresh Mass ◽  
Short Term ◽  
Tissue Concentrations ◽  
Term Experiment ◽  
Whole Plant ◽  
Solute Accumulation ◽  
Long Term Experiment ◽  
Short Term Experiment ◽  
Hydroponically Grown

The NaCl effects on the growth and inorganic solute accumulation were studied on 30-day-old cashew plants (Anacardium occidentale L.) hydroponically grown for 8 days (short term) and 40 days (long-term) with NaCl at different levels. The shoot fresh mass yielded after 40 days, in response to 50 and 100 mol m-3 NaCl, decreased by 25 and 75%, respectively. This decrease was markedly low in root fresh mass, which did not change under 50 mol m-3 NaCl and decreased nearly to 30% under 100 mol m-3 NaCl, as compared to control plants. In short-term experiment, salinity induced only slight changes of K+ tissue concentrations in the whole plant. In the long-term experiment, K+ tissue concentrations were substantially decreased, particularly in roots. In response to time and increasing levels of salinity, Na+ and Cl- ions concentrations reached toxic levels in leaves. Thus, cashew plants already from the 4th day of salinity stress exhibited earlier symptoms of ionic toxicity, and therefore they were not able to regulate metabolic and physiological functions under these harmful conditions.

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