The impact of long-term water stress on relative growth rate and morphology of needles and shoots of Metasequoia glyptostroboides seedlings: research toward identifying mechanistic models

2011 ◽  
Vol 143 (1) ◽  
pp. 10-20 ◽  
Author(s):  
Yanxiang Zhang ◽  
Maria Alejandra Equiza ◽  
Quanshui Zheng ◽  
Melvin T. Tyree
Keyword(s):  
Growth Rate ◽  
Water Stress ◽  
Relative Growth Rate ◽  
Mechanistic Models ◽  
Metasequoia Glyptostroboides ◽  
Relative Growth ◽  
The Impact

Water Relations of Beans I. Effects of Water Stress on Growth and Flowering

1969 ◽  
Vol 5 (3) ◽  
pp. 195-207 ◽  
Author(s):  
A. H. El Nadi
Keyword(s):  
Growth Rate ◽  
High Temperature ◽  
Water Stress ◽  
Plant Growth ◽  
Relative Growth Rate ◽  
Broad Bean ◽  
Day Length ◽  
Vegetative Period ◽  
Relative Growth ◽  
Made In

SummaryExperiments were made in glasshouses, growth cabinets and growth rooms to study the differential responses of the broad bean to water stress during the vegetative and flowering phases of growth. Plants in the flowering phase proved to be more sensitive to drought than in the vegetative period, and there were different responses (Relative Growth Rate) to temperature at different stages of plant growth. Day length and temperature influenced the position of the earliest flower initials on the stem, and intensity of flower shedding was aggravated by high temperature.

Modulation of relative growth rate and its components by water stress in Mediterranean species with different growth forms

Oecologia ◽  
2005 ◽  
Vol 145 (1) ◽  
pp. 21-31 ◽  
Author(s):  
Jeroni Galmés ◽  
Josep Cifre ◽  
Hipólito Medrano ◽  
Jaume Flexas
Keyword(s):  
Growth Rate ◽  
Water Stress ◽  
Relative Growth Rate ◽  
Growth Forms ◽  
Mediterranean Species ◽  
Relative Growth

scholarly journals Impact of Information and Communication Technologies on Research and Development: A Case of University of the Punjab-Pakistan

2014 ◽  
Vol 15 ◽  
pp. 47-53 ◽  
Author(s):  
Nosheen Fatima Warriach ◽  
Muzamil Tahira
Keyword(s):  
Growth Rate ◽  
Relative Growth Rate ◽  
Information And Communication Technologies ◽  
Research Productivity ◽  
Doubling Time ◽  
Research Output ◽  
Communication Technologies ◽  
Relative Growth ◽  
Information And Communication ◽  
The Impact

This study explores the research trends at Pakistani universities by highlighting the use of Information and Communication Technologies (ICTs) in the research process and its productivity. It also investigates the impact of Higher Education Commission (HEC) initiatives for research output in Pakistani universities in general and PU, in particular. It explores the essential ICT skills to increase research productivity as perceived by researchers from the Faculty of Social and Behavioral Sciences through structured interviews. An analysis of HEC of Pakistan and PU websites is carried out. The statistics of these websites shows that there is an increase in the number of research articles and PhDs produced every year. Data show that the respondents are not fully utilizing the pricey electronic sources provided by the HEC, yet there is a yearly increase in a number of PhDs produced and published research. The relative growth rate of research productivity and doubling time were not constant. It is also observed that doubling time has increased while the relative growth rate is going to decrease.

scholarly journals DIURNAL FLUCTUATIONS IN SIZE OF TOMATO FRUIT

HortScience ◽  
1991 ◽  
Vol 26 (6) ◽  
pp. 779D-779 ◽  
Author(s):  
Juan Carlos Diaz-Perez ◽  
Kenneth Shackel
Keyword(s):  
Growth Rate ◽  
Relative Growth Rate ◽  
Fruit Development ◽  
Tomato Fruit ◽  
Tomato Fruits ◽  
Relative Growth ◽  
Midday Depression ◽  
Zero Values ◽  
Diurnal Fluctuations

Tomato fruits showed diurnal fluctuations in size in addition to long-term irreversible enlargement. Diurnal fluctuations were highly related to the stage of fruit development. In all stages, the maximum relative growth rate occurred in the morning and the minimum RGR at midday. Midday depression of RGR became more severe as fruits developed. In young fruits, RGR was nearly constant over the day. A small depression in growth was observed only at midday. In more developed fruits, RGR was positive during the first half of the day, followed by near zero values in the afternoon, and a. recovery in early night. In mature fruits, overall fruit growth was minimum and RGR was positive only in the morning. Fruit shrinkage was often seen at midday in mature fruits.

Growth relationships in silver maple seedlings fumigated with O3 and SO2

1983 ◽  
Vol 13 (2) ◽  
pp. 298-302 ◽  
Author(s):  
K. F. Jensen
Keyword(s):  
Growth Rate ◽  
Leaf Area ◽  
Relative Growth Rate ◽  
Growth Analysis ◽  
Dry Weight ◽  
Ozone Treatment ◽  
Dry Matter Accumulation ◽  
Relative Growth ◽  
Silver Maple ◽  
The Impact

Growth analysis was used to measure the impact of low levels of ozone, alone and with sulfur dioxide, on the growth of silver maple (Acersaccharinum L.) seedlings. The seedlings were fumigated for up to 60 consecutive days with cither 0.05, 0.1, or 0.2 ppm ozone, alone and with 0.1 ppm SO2 for 12 h per day. Dry weight and leaf area development curves were calculated from data collected at 10-day intervals throughout the study. Growth analysis variables were calculated from these curves. Three variables, relative growth rate, relative leaf area growth rate, and relative leaf weight growth rate, were reduced by 0.2 ppm ozone and decreased even further when 0.1 ppm SO2 was applied. Neither the 0.05 nor 0.1 ppm ozone treatment decreased the relative growth rate of the silver maple seedlings. Even small differences in growth rate may produce large differences in dry matter accumulation over a growing season.

Influence of Water Stress on Water Relations and Growth of a Tropical (C4) Grass, Panicum maximum var. trichoglume

1975 ◽  
Vol 2 (4) ◽  
pp. 581 ◽  
Author(s):  
TT Ng ◽  
JR Wilson ◽  
MM Ludlow
Keyword(s):  
Growth Rate ◽  
Water Stress ◽  
Water Potential ◽  
Water Content ◽  
Soil Water ◽  
Leaf Area ◽  
Soil Water Content ◽  
Relative Growth Rate ◽  
Leaf Water ◽  
Relative Growth

The effects of recurring cycles of short-term water stress on the water relations and growth of P. maximum var. trichoglume in pots of soil were investigated under controlled conditions. As soil water content decreased there was an increase in the resistance to water movement in the soil-plant system. Leaf stomatal resistance increased and concomitantly transpiration rate decreased when soil water content fell below 37 % (soil water potential of - 1 .0 bars) and leaf water potentials were less than - 6 bars. The leaf water potential at wilting (- 8 to - 10 bars) and the relation between leaf water potential and relative water content changed with leaf position on the tiller. The death of early-formed leaves on the plants was accelerated by water stress but, in contrast, the later-formed leaves died more rapidly in the control (unstressed) treatment so that finally the control plants had a higher proportion of dead leaves. Plant growth was reduced at soil water contents above the permanent wilting point. Reduction in net assimilation rate was the main determinant of lower relative growth rate of stressed plants over the initial cycles of stress but subsequently, as leaf area expansion was reduced, leaf area ratio also had a significant influence. Water stress influenced growth directly, and also indirectly via its effect on plant development (ontogeny). Two techniques were used to separate the direct from the indirect effects on relative growth rate Some published data which suggest a stimulation of growth rate after the relief of stress are re-interpreted and the effect is shown to be due mainly to differences in ontogeny between stressed and control treatments

scholarly journals VARIACIÓN ESPACIO-TEMPORAL DE LA BIOMASA DEL ALGA CAULERPA SERTULARIOIDES EN POBLACIONES NATURALES Y EN CONDICIONES DE CULTIVO EN ESTANQUES DE CAMARÓN EN LA BAHÍA DE TUMACO, PACÍFICO COLOMBIANO

2016 ◽  
Vol 43 (1) ◽  
Author(s):  
Hernel Marín Salgado ◽  
Enrique Javier Peña Salamanca
Keyword(s):  
Growth Rate ◽  
Relative Growth Rate ◽  
Algal Biomass ◽  
Algal Species ◽  
Natural Populations ◽  
Ammonia Nitrogen ◽  
Shrimp Ponds ◽  
Relative Growth ◽  
Culture Techniques ◽  
The Impact

The biomass of natural populations and biomass under cultured conditions in shrimp ponds of the green alga Caulerpa sertularioides (Chlorophyta, Bryopsidales) was evaluated during March-December 2010 and January- June 2011. The algal biomass in the estuary was collected monthly at low tide using 625 cm2 quadrants. Water quality variables, such as dissolved oxygen, salinity, temperature, Secchi disk, NO3 -, NH3 and PO4 3-, were taken simultaneously with algal samples. Algal biomass was taken to the lab to remove debris. Afterward, wet and dry weights were obtained to get final biomass. Relative growth rate (RGR% d-1) in ponds as well as physicochemical variables was evaluated weekly. Growth rates of plants registered a mean of 1.69 % day-1 (± 0.97). There were no significant differences (p = 0.315) in terms of biomass of C. sertularioides between Natal and Pajal creeks, showing averages between 4.09 and 4.67 g cm-2. Algal biomass showed significant differences between seasons (p = 0.000039), with highest values recorded between July and September. Salinity in Natal creek showed a direct relationship with seasonal variation of algal biomass (p = 0.019), with highest values of biomass in July-September related to higher levels of salinity in the study area. In contrast, salinity values and algal biomass in Pajal creek did not show significant relationship (p = 0.97). Nitrates, ammonia nitrogen, and orthophosphate were not significant with respect to changes in algal biomass (p = 0.93; p = 0.33; p = 0.55, respectively). Significant differences (p = 0.0021) between biomass of natural populations and algal biomass in shrimp ponds were reported, with higher values in cultured conditions, being those three times the biomass of natural creeks. Values of algal biomass from natural creeks suggested the importance of perform culture techniques, since natural populations would not sustain a commercial exploitation of this species. This study reports the first data of growth of a potential algal species and it is necessary to develop additional experiments to assess the impact of additional environmental factors on the relative growth rate.

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