scholarly journals Assimilation apparatus variability of beech transplants grown in variable light conditions of blue spruce shelter

2008 ◽  
Vol 54 (No. 11) ◽  
pp. 491-496 ◽  
Author(s):  
O. Špulák
Keyword(s):  
Photosynthetic Capacity ◽  
Leaf Size ◽  
Absorption Capacity ◽  
Light Conditions ◽  
Chemical Parameters ◽  
The Czech Republic ◽  
Blue Spruce ◽  
Specific Leaf Mass ◽  
Phosphorus And Potassium ◽  
Variable Light

The paper valuates the differences in the selected characteristics of the assimilation apparatus of beech transplants growing in various light conditions of blue spruce small pole stage in the Jizerské hory Mts. in the Czech Republic. The leaf area, chemical parameters, and photosynthetic capacity measured by the method of chlorophyll fluorescence were established. Light conditions of individual beech trees were determined by means of processing a hemisphere photograph of the crown space. The research revealed a significant trend of decreasing nitrogen content with increasing irradiance of the beech. The foliage of the sheltered beech trees exhibited higher contents of phosphorus and potassium. The average specific leaf mass (SLM) of the beech under crowns was lower (0.303 contrary to 0.499 g/dm<sup>2</sup> in gap) and the respective variants did not differ in average leaf size. A significantly higher maximum fluorescence and a maximum quantum yield (0.854 contrary to 0.803 in gap) were found under crowns. A significant variance was also observed in the absorption capacity. It follows that the beech showed adaptation to the light conditions defined by its location within the stand of blue spruce.

scholarly journals Evaluation of Soil S Pools under 23 Years of Maize Monoculture

Agronomy ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 2376
Author(s):  
Pavel Suran ◽  
Martin Kulhánek ◽  
Jiří Balík ◽  
Jindřich Černý ◽  
Ondřej Sedlář
Keyword(s):  
High Dose ◽  
The Czech Republic ◽  
S Uptake ◽  
Biomass Yields ◽  
Entire Experiment ◽  
Initial Content ◽  
Phosphorus And Potassium ◽  
Very High ◽  
Sulfur Nutrition

Sulfur nutrition is a critical part of proper crop growth and development. In our study, biomass yields (BY) and S uptake were investigated on long-term maize monoculture on haplic luvisol soil during the 23 years of this trial, as well as changes in water extractable (Sw), adsorbed (Sads), mineral (Sav), and pseudo-total S (St) fractions. Treatments used in this study are: (1) Control (Cont); (2) ammonium sulfate (AS); (3) urea and ammonium nitrate (UAN); (4) UAN + phosphorus and potassium (UAN + PK); (5) UAN + phosphorus, magnesium, sulfur (UAN + PMgS); and (6) Fallow. Recently, the Mehlich 3 method started to be used in the Czech Republic to determine content of plant available S. Using this method, it was found that the content of S extracted by Mehlich 3 (SM3) closely correlates to Sav in both topsoil and subsoil (r = 0.958 in 1997 and 0.990 in 2019, both at p < 0.001). We also found that, on average, during the entire experiment, all treatments had increased yields over Cont (135–147%) and increased S uptake (291, 192, 180, and 246% of Cont for AS, UAN, UAN + PK, and UAN + PMgS, respectively). Examining the changes from 1997 to 2019 in topsoil (0–30 cm depth), we discovered a decrease of S content in Sw, Sads, Sav, and St fractions on all treatments to an average of 34.6%, 65.8%, 42.2%, and 78.6% of their initial values. The exception was AS treatment, which doubled its initial content in mineral fractions and maintained the same levels of St, and which we attribute to the very high dose of S on this treatment (142 kg ha−1 year−1). Using the simple balance method, AS and UAN + PMgS treatments lost 142.2 and 95.3 kg S ha−1 year−1 to other sinks, except plant uptake, from the entire soil profile (0–60 cm) during 23 years of experiment. Other treatments also show significant losses with the exception of Fallow. Given these results, it is clear that content of sulfur in soil is generally decreasing and attention should be paid mainly towards minimizing of its losses.

The effect of fluctuating light on canopy photosynthesis: a focus on a chlorophyll-deficient Soybean mutant

2021 ◽  
Author(s):  
Nicole Salvatori
Keyword(s):  
Steady State ◽  
Dynamic Environment ◽  
Regulatory System ◽  
Total Carbon ◽  
Light Transmittance ◽  
Photochemical Quenching ◽  
Natural Environments ◽  
Deficient Mutant ◽  
Light Conditions ◽  
Variable Light

&lt;p&gt;In natural environments plants are subjected to variable light conditions and therefore need an efficient regulatory system to regulate photosynthesis and the downstream metabolism. Most of the measurements available are taken at steady state and at leaf level but those may overestimate total carbon uptake in a more dynamic environment. Furthermore, some plants may be more adapted than others to deal with light fluctuations and therefore is difficult to draw general conclusions. We then grew a commercial soybean variety and a chlorophyll deficient mutant in a recently developed growth chamber system (DYNAMISM) which allowed to obtain instantaneous gas exchange data at canopy level for several weeks. By doing so we could investigate both short term responses and long term adaptations to light dynamic conditions of the two varieties. At steady state, chlorophyll deficient crops are thought to have a similar or even a higher photosynthetic rate compared to the green wildtypes, enhanced by a higher light transmittance throughout the canopy. But little is known about how they respond to fluctuations in light. The two varieties were grown either in fluctuating (F) or non-fluctuating (NF) light conditions to evaluate how variable light would affect biomass accumulation. Two different light treatments were applied, low light (LL) and high light (HL) with different light intensities and amplitude of fluctuations. The LL treatment did not entail any difference among F and NF in both varieties. The chlorophyll-deficient mutant was instead found to be susceptible to the fluctuations of light in the HL treatment, by accumulating less biomass. It is hypothesised that this might be due to its longer non&amp;#8208;photochemical quenching relaxation time &amp;#160;in light transitions, but other acclimatation mechanisms need to be investigated.&lt;/p&gt;

The photosynthetic response of American chestnut seedlings to differing light conditions

2007 ◽  
Vol 37 (9) ◽  
pp. 1714-1722 ◽  
Author(s):  
Heather M. Joesting ◽  
Brian C. McCarthy ◽  
Kim J. Brown
Keyword(s):  
Deciduous Forest ◽  
Photosynthetic Capacity ◽  
Dark Respiration ◽  
Nitrogen Concentration ◽  
American Chestnut ◽  
Control Treatment ◽  
Carbon Gain ◽  
Leaf Mass Per Area ◽  
Light Conditions ◽  
Eastern Deciduous Forest

Restoration attempts to reintroduce American chestnut trees to the eastern deciduous forest by means of a disease-resistant Chinese–American hybrid seed are in progress. Knowing the light conditions required for optimum seedling performance is necessary to maximize the success of reintroduction. American chestnut ( Castanea dentata (Marsh.) Borkh.) seedlings were planted in two replicate forests in Vinton County, Ohio, in areas that had been thinned (more available light) and in control areas (intact canopy, less available light). The photosynthetic capacity of 12 seedlings per treatment was assessed using an infrared gas-exchange analyzer. Seedlings in the thinned treatment reached light-saturating rates of photosynthesis at an irradiance level approximately 33% higher than did the seedlings in the control treatment. Seedlings grown in the thinned treatment had a significantly greater maximum rate of photosynthesis (Amax), dark respiration rate (Rd), and daily carbon gain per seedling than seedlings grown in the control treatment. The light compensation point (LCP), quantum efficiency (ϕ), leaf mass per area (LMA), and leaf nitrogen concentration per unit leaf area (Narea) were not significantly different between treatments. American chestnut seedlings in the thinned treatment clearly maximize leaf-level photosynthetic capacity. These results will aid land managers in planning reintroduction trials by providing information on the light conditions required for maximum seedling success.

Leaf morphology and photosynthetic rate in birch seedlings and stump sprouts

1990 ◽  
Vol 20 (7) ◽  
pp. 952-960 ◽  
Author(s):  
A. Kauppi ◽  
M. Kiviniitty ◽  
A. Ferm
Keyword(s):  
Nitrogen Content ◽  
Shoot Growth ◽  
Photosynthetic Capacity ◽  
Leaf Size ◽  
Growing Season ◽  
Optimum Temperature ◽  
Factors Affecting ◽  
Mesophyll Structure ◽  
Rate Of Photosynthesis ◽  
Seed Origin

Comparisons were made of the leaves of sprout-origin and seed-origin shoots of Betulapubescens Ehrh. and B. pendula Roth grown under constant or varying temperatures. Particular attention was paid to leaf structure and other factors affecting the rate of photosynthesis. Differences in shoot growth, leaf size, mesophyll structure, and chlorophyll and nitrogen content were observed between the sprouts and seedlings of both species over the course of the growing season. Many of these differences were reflected in the photosynthesis measurements. The sprouts of both species appeared to show a better photosynthetic capacity in their first growing season than the seedlings, and they continued their height growth longer into the autumn. A distinct decline in the level of photosynthesis took place during the growing season. The results suggest that perhaps because of their higher chlorophyll and nitrogen content, young sprouts benefit more from the extremes of temperature at the beginning and end of the growing season than seedlings of the same age. The optimum temperature was the same for sprouts and seedlings of both species. Whether the superior photosynthetic capacity of sprouts compared with seedlings is maintained in later years remains to be resolved.

Photosynthesis, vegetative habit and culinary properties of sage (Salvia officinalis) in response to low-light conditions

2014 ◽  
Vol 94 (5) ◽  
pp. 881-889 ◽  
Author(s):  
Christine Mapes ◽  
Yan Xu
Keyword(s):  
Protein Content ◽  
Plant Height ◽  
Soluble Protein ◽  
Photochemical Efficiency ◽  
Leaf Size ◽  
Salvia Officinalis ◽  
Light Conditions ◽  
Soluble Protein Content ◽  
Low Light ◽  
Double Blind

Mapes, C. and Xu, Y. 2014. Photosynthesis, vegetative habit and culinary properties of sage (Salvia officinalis) in response to low-light conditions. Can. J. Plant Sci. 94: 881–889. Culinary sage (Salvia officinalis) is known to grow better at sunny locations with good drainage. However, when there is a necessity to propagate it in controlled environments with minimal additional lighting, or at shady locations, how significantly its growth and production would be restricted has not been well investigated. The objective of this study was to examine the responses of sage grown in a greenhouse over the winter when ambient light in the greenhouse is lower than 212 μmol m−2 s−1 (or a daily light integral of 9.2 mol m−2 d−1). Sage seedlings were planted in growing media and covered with various shade cloths to reach 70, 50 and 30% of the ambient irradiance. Photochemical efficiency and in situ chlorophyll status were estimated at 7, 21, and 56 d. The daily leaf emergence rate was calculated by monitoring changes in leaf number. Plant height, leaf size, biomass, aroma rating and soluble protein content of the sage plants grown under various light levels were measured at 84 d. The results indicate that light impacted the integrity of chloroplasts and the photosynthetic capacity of sage plants, as manifested by the lower the light level, the more the declines in variable fluorescence/maximal fluorescence and chlorophyll content index. Biochemical analysis revealed that the concentration of chlorophyll (per gram leaf dry mass) slightly increased under 50 and 30% light, but that of carotenoids was not changed. Light also affected the vegetative habit of sage plants. With reduced light intensity, plant height increased, whereas leaf size and number decreased. Double-blind aroma testing suggested that adequate light intesity might be required for the biosynthesis of essential oil in sage, attenuating its aroma. The soluble protein content in sage leaves declined at 50 and 30% light, suggesting a deminished source of essential amino acids contained in the plant. In summary, sage responds sensitively to reducing irradiance, which directly restricts its photosynthesis, and thus alters its vegetative growth and culinary properties.

Effects of a Windstorm and Forest Fire on Chemical Losses from Forested Watersheds and on the Quality of Receiving Streams

1980 ◽  
Vol 37 (3) ◽  
pp. 328-334 ◽  
Author(s):  
D. W. Schindler ◽  
R. W. Newbury ◽  
K. G. Beaty ◽  
J. Prokopowich ◽  
T. Ruszczynski ◽  
...  
Keyword(s):  
Water Quality ◽  
Forest Fire ◽  
Stream Water ◽  
Water Yield ◽  
Chemical Parameters ◽  
Stream Water Quality ◽  
Forested Watersheds ◽  
Phosphorus And Potassium ◽  
Nitrogen Phosphorus

A severe natural windstorm followed by a high intensity forest fire caused significant increases in runoff and in losses of nitrogen, phosphorus, and potassium from two small Precambrian watersheds. Both the windstorm and the fire had significant effects on water and chemical yields. Water yields in the two basins were 1.6 and 1.8 times the pre-impact means, respectively, in the year after the burn. Maximum chemical losses were observed for nitrate, with values of 3.4 and 9 times the pre-impact means for the two basins in the year after the burn. Increases in annual yields of most chemical parameters were 1.1 to 2.9 times the background. Both increased concentrations and increased flow volumes appear to be responsible for the increased nutrient losses.Key words: forest fire, windstorm, stream water quality, phosphorus, nitrogen, potassium losses, water yield

scholarly journals Analysis of Selected Environmental Indicators in the Cultivation System of Energy Crops

2017 ◽  
Vol 14 (2) ◽  
pp. 64-69
Author(s):  
Božena Š Šoltysová ◽  
Martin Danilovič
Keyword(s):  
Organic Carbon ◽  
Nitrogen Fertilization ◽  
Energy Crops ◽  
Environmental Indicators ◽  
Soil Reaction ◽  
Available Phosphorus ◽  
Organic Carbon Content ◽  
Chemical Parameters ◽  
Miscanthus Giganteus ◽  
Phosphorus And Potassium

Abstract The changes of selected chemical parameters were observed in Gleyic Fluvisols. The field experiment was established as a twofactor experiment with four energy crops (Arundo donax L., Miscanthus × giganteus, Elymus elongatus Gaertner, Sida hermafrodita) and two variants of fertilization (nitrogen fertilization in rate 60 kg ha-1, without nitrogen fertilization). Soil samples were taken from the depth of 0 to 0.3 m at the beginning of the experiment in the autumn 2012 and at the end of reference period in the autumn 2015. Land management conversion from market crops to perennial energy crops cultivation has influenced changes of selected soil chemical parameters. The contents of soil organic carbon were affected by cultivated energy crops differently. It was found out that Arundo increased the organic carbon content and Miscanthus, Elymus and Sida decreased its content. At the same time, the same impact of the crops on content of available phosphorus and potassium and soil reaction was found. It was recorded that each cultivated crop decreased the soil reaction and available phosphorus content and increased the content of available potassium.

scholarly journals Drought stress imposes reversible photosynthetic damage under fluctuating light conditions in crops

2021 ◽  
Author(s):  
Kazuma Sakoda ◽  
Kazuki Taniyoshi ◽  
Wataru Yamori ◽  
Yu Tanaka
Keyword(s):  
Drought Stress ◽  
Photosynthetic Capacity ◽  
Crop Growth ◽  
Growth And Yield ◽  
Carbon Gain ◽  
Limiting Factor ◽  
Photosynthetic Induction ◽  
Light Conditions ◽  
Fluctuating Light ◽  
Dynamic Photosynthesis

Drought stress is a major limiting factor for crop growth and yield. Water availability in the field can cyclically change between drought and rewatering conditions, depending on precipitation patterns. Concurrently, light intensity under field conditions can fluctuate, inducing dynamic photosynthesis and transpiration during crop growth period. The present study aimed to characterize carbon gain and water use in fluctuating light under drought and rewatering conditions by conducting gas exchange measurements in two major crops, namely rice and soybean. In both crops, drought stress reduced steady-state photosynthesis and/or photosynthetic capacity, and delayed photosynthetic induction even when it had relatively small impact on photosynthetic capacity, suggesting that the drought effects on photosynthesis should be evaluated based on induction, maximum, and steady states. This delayed photosynthetic induction resulted in a substantial loss of carbon gain under fluctuating light conditions, which can be a limiting factor for crop growth and yield in the field. Meanwhile, rewatering after drought conditions completely recovered photosynthetic capacity and induction in both crops, whereas drought experience would be memorized to slow down the stomatal opening. Therefore, the stability of photosynthetic induction can be a promising target to improve drought tolerance during crop breeding in the future.

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