Photosynthetic Acclimation of Alocasia macrorrhiza (L.) G. Don

1988 ◽  
Vol 15 (2) ◽  
pp. 107 ◽  
Author(s):  
WS Chow ◽  
L Qian ◽  
DJ Goodchild ◽  
JM Anderson
Keyword(s):  
Charge Density ◽  
Leaf Area ◽  
Cell Walls ◽  
Surface Charge Density ◽  
Leaf Tissue ◽  
O2 Evolution ◽  
Palisade Cell ◽  
Unit Leaf Area ◽  
Unit Leaf ◽  
Growth Irradiance

The photosynthetic acclimation of Alocasia macrorrhiza (L.) G. Don, a species naturally occurring in deep shade in rainforests, has been studied in relation to a wide range of controlled irradiances during growth (~3-780 �mol photons m-2 s-1 of fluorescent or incandescent light, 10 h light/ 14 h dark). At the maximum growth irradiances, the light- and CO2-saturated rates of O2 evolution per unit leaf area were ~4 times as high as at low irradiance, and approached those of glasshouse-grown spinach. Growth at maximum irradiances reduced the quantum yield of O2 evolution only slightly. Changes in the anatomy of leaf tissue, the ultrastructure of chloroplasts and the composition of chloroplast components accompanied the changes in photosynthetic functional characteristics. At low growth irradiance, palisade cell chloroplasts were preferentially located adjacent to the distal periclinal cell walls and had large granal stacks, and the destacked thylakoids had a very low surface charge density. In contrast, at higher growth irradiance, palisade cell chloroplasts were preferentially located adjacent to the anticlinal cell walls; they had small granal stacks, large stromal space, and a high surface charge density on the destacked thylakoids. The number of chloroplasts per unit section length increased with growth irradiance. Ribulosebisphosphate carboxylase activity per unit leaf area increased markedly with irradiance. Photosystem II, cytochrome f and latent ATPase activity per unit chlorophyll increased to a lesser extent. While the chlorophyll a/chlorophyll b ratio increased substantially with growth irradiance, the chlorophyll content per unit leaf area declined slightly. Our results show that coordinated changes in the structure of leaf tissue, and the organisation and composition of chloroplast components are responsible for Alocasia being capable of acclimation to high as well as low irradiance.

Stomatal Development During Leaf Expansion in Tobacco and Sunflower

1975 ◽  
Vol 23 (2) ◽  
pp. 253 ◽  
Author(s):  
HM Rawson ◽  
CL Craven
Keyword(s):  
Leaf Area ◽  
Stomatal Density ◽  
Stomatal Development ◽  
Developmental Patterns ◽  
Full Size ◽  
Unit Leaf Area ◽  
Unit Leaf ◽  
Wide Range ◽  
Young Leaves ◽  
Different Levels

Changes in stomatal density and size were followed in tobacco and sunflower leaves expanding from 10% of final area (10% Amax) to Amax under different levels of radiation. Lower radiation increased final leaf area, reduced stomatal densities, and increased area per stoma but had little effect on stomatal area per unit leaf area at Amax. In very young leaves (20% Amax) there was a wide range in the sizes of individual stomata, some stomata being close to full size, but by Amax differences were small. The possible relationship between the developmental patterns described and photosynthesis is briefly discussed.

Effect of Interspecific Interference, Light Intensity, and Soil Moisture on Soybean (Glycine max), Common Cocklebur (Xanthium strumarium), and Sicklepod (Cassia obtusifolia) Water Uptake

Weed Science ◽  
1993 ◽  
Vol 41 (4) ◽  
pp. 534-540 ◽  
Author(s):  
Ronald E. Jones ◽  
Robert H. Walker
Keyword(s):  
Soil Moisture ◽  
Light Intensity ◽  
Leaf Area ◽  
Water Uptake ◽  
Root Weight ◽  
Pressure Potential ◽  
Unit Leaf Area ◽  
Unit Leaf ◽  
Shoot Weight ◽  
The Relationship

Greenhouse and growth chamber experiments with potted plants were conducted to determine the effects of interspecific root and canopy interference, light intensity, and soil moisture on water uptake and biomass of soybean, common cocklebur, and sicklepod. Canopy interference and canopy plus root interference of soybean with common cocklebur increased soybean water uptake per plant and per unit leaf area. Root interference with soybean decreased common cocklebur water uptake per plant. Canopy interference of soybean with sicklepod increased soybean water uptake per unit leaf area, while root interference decreased uptake per plant. Combined root and canopy interference with soybean decreased water uptake per plant for sicklepod. Soybean leaf area and shoot weight were reduced by root interference with both weeds. Common cocklebur and sicklepod leaf area and shoot weight were reduced by root and canopy interference with soybeans. Only common cocklebur root weight decreased when canopies interfered and roots did not. The relationship between light intensity and water uptake per unit leaf area was linear in both years with water uptake proportional to light intensity. In 1991 water uptake response to tight was greater for common cocklebur than for sicklepod. The relationship between soil moisture level and water uptake was logarithmic. Common cocklebur water uptake was two times that of soybean or sicklepod at −2 kPa of pressure potential. In 1991 common cocklebur water uptake decreased at a greater rate than soybean or sicklepod in response to pressure potential changes from −2 to −100 kPa.

Carbon Isotope Discrimination and Gas Exchange in Coffea arabica During Adjustment to Different Soil Moisture Regimes

1992 ◽  
Vol 19 (2) ◽  
pp. 171 ◽  
Author(s):  
FC Meinzer ◽  
NZ Saliendra ◽  
C Crisosto
Keyword(s):  
Soil Moisture ◽  
Gas Exchange ◽  
Leaf Area ◽  
Coffea Arabica ◽  
Carbon Isotope Discrimination ◽  
Total Leaf Area ◽  
Unit Leaf Area ◽  
Unit Leaf ◽  
Moisture Regimes ◽  
Area Basis

Although carbon isotope discrimination (Δ) has been reported to decline in plants growing under reduced soil moisture, there is little information available concerning the dynamics of adjustments in Δ and gas exchange following a change in soil water availability. In this study Δ, photosynthetic gas exchange, and growth were monitored in container-grown coffee (Coffea arabica L.) plants for 120 days under three soil moisture regimes. At the end of 120 d, total leaf area of plants irrigated twice weekly was one half that of plants irrigated twice daily, although their assimilation rates on a unit leaf area basis were nearly equal throughout the experiment. This suggested that maintenance of nearly constant photosynthetic characteristics on a unit leaf area basis through maintenance of a smaller total leaf area may constitute a major mode of adjustment to reduced soil moisture availability in coffee. Intrinsic water-use efficiency (WUE) predicted from foliar Δ values was highest in plants irrigated weekly, intermediate in plants irrigated twice weekly and lowest in plants irrigated twice daily. When instantaneous WUE was estimated from independent measurements of total transpiration per plant and assimilation on a unit leaf area basis, the reverse ranking was obtained. The lack of correspondence between intrinsic and instantaneous WUE was attributed to adjustments in canopy morphology and leaf size in the plants grown under reduced water supply which enhanced transpiration relative to assimilation. Values of Δ predicted from the ratio of intercellular to ambient CO2 partial pressure determined during gas exchange measurements were not always consistent with measured foliar Δ. This may have resulted from a patchy distribution of stomatal apertures in plants irrigated weekly and from a lag period between adjustment in gas exchange and subsequent alteration in Δ of expanding leaves. The importance of considering temporal and spatial scales, and previous growth and environmental histories in comparing current single leaf gas exchange behaviour with foliar Δ values is discussed.

Leaf mass per unit leaf area decreases as light is eliminated within almond trees (Prunus dulcis)

2018 ◽  
pp. 157-162
Author(s):  
D. Monks ◽  
C. Taylor ◽  
M.T. Treeby
Keyword(s):  
Leaf Area ◽  
Prunus Dulcis ◽  
Unit Leaf Area ◽  
Leaf Mass ◽  
Unit Leaf ◽  
Almond Trees

Photosynthesis in Conifers Computed Per Unit Leaf Area, Dry Weight, Volume, Chlorophyll Content and Respiratory Rate

Ecology ◽  
1959 ◽  
Vol 40 (4) ◽  
pp. 738-738 ◽  
Author(s):  
Jacob Verdun
Keyword(s):  
Respiratory Rate ◽  
Leaf Area ◽  
Chlorophyll Content ◽  
Dry Weight ◽  
Unit Leaf Area ◽  
Unit Leaf

scholarly journals Growth Analysis and Photosynthesis Measurements of Cucumber Seedlings Grown under Light with Different Red to Far-red Ratios

HortScience ◽  
2016 ◽  
Vol 51 (7) ◽  
pp. 843-846 ◽  
Author(s):  
Toshio Shibuya ◽  
Ryosuke Endo ◽  
Yoshiaki Kitaya ◽  
Saki Hayashi
Keyword(s):  
Leaf Area ◽  
Growth Parameters ◽  
Weight Ratio ◽  
Net Photosynthesis ◽  
Dry Weight ◽  
Unit Leaf Area ◽  
Cucumber Seedlings ◽  
Unit Leaf ◽  
Net Assimilation ◽  
Normal Light

Light with a higher red to far-red ratio (R:FR) than sunlight reduces plant growth, but the cause has not been firmly established. In the present study, cucumber seedlings were grown under normal light (similar to sunlight; R:FR = 1.4) from metal-halide lamps or high-R:FR light (R:FR = 4.3) created by transmitting their light through FR-absorbing film, and then their growth parameters and photosynthesis were compared. The relative growth rate (RGR) at high R:FR was 92% of that under normal R:FR, although the net assimilation rate (NAR) did not differ between the treatments, indicating that changes in net photosynthesis per unit leaf area did not cause the growth inhibition at high R:FR. The CO2 exchange per unit leaf area did not differ between the treatments, which supports this hypothesis. The leaf area ratio (LAR) of total plant dry weight of high R:FR seedlings to that of normal R:FR seedlings was also 92%. This suggests that growth suppression in the high R:FR seedlings was caused mainly by decreased LAR. The specific leaf area (SLA) and leaf weight ratio (LWR), components of LAR, under high-R:FR light were 89% and 105%, respectively, of those under normal light, indicating that the smaller LAR at high R:FR mainly results from suppressed leaf enlargement per unit leaf dry matter.

A Measurement of the Total Mass of Spray and Irrigation Mixtures Intercepted by Small Whole Plants

1997 ◽  
Vol 11 (3) ◽  
pp. 466-472 ◽  
Author(s):  
R. D. Wauchope ◽  
H. R. Sumner ◽  
C. C. Dowler
Keyword(s):  
Leaf Area ◽  
Total Mass ◽  
Spray Deposition ◽  
Unit Leaf Area ◽  
Unit Leaf ◽  
Cotton Plants ◽  
Before And After ◽  
Corn Plants ◽  
Whole Plants

A plant-weighing procedure was used to measure the total mass of spray mixture intercepted by small whole corn and cotton plants. Mixtures of water and water plus crop oil concentrate or spreader–sticker were applied at spray volumes of 280 to 28,000 L/ha. The plants were weighed before and after passing under the spray and leaf areas, and shoot fresh and dry weights for each plant were measured. Spray deposition increased with spray volumes but not proportionally. Corn plants were larger than cotton plants and retained more spray per plant; however, cotton retained more spray per unit leaf area. The two adjuvants had similar effects on deposition, tending to increase it in corn and decrease it in cotton.

scholarly journals Variation in Chlorophyll Content per Unit Leaf Area in Spring Wheat and Implications for Selection in Segregating Material

PLoS ONE ◽  
2014 ◽  
Vol 9 (3) ◽  
pp. e92529 ◽  
Author(s):  
John Hamblin ◽  
Katia Stefanova ◽  
Tefera Tolera Angessa
Keyword(s):  
Leaf Area ◽  
Chlorophyll Content ◽  
Spring Wheat ◽  
Unit Leaf Area ◽  
Unit Leaf

Reexamining the empirical relation between plant growth and leaf photosynthesis

2006 ◽  
Vol 33 (5) ◽  
pp. 421 ◽  
Author(s):  
Eric L. Kruger ◽  
John C. Volin
Keyword(s):  
Gas Exchange ◽  
Plant Growth ◽  
Leaf Area ◽  
Leaf Gas Exchange ◽  
Empirical Relation ◽  
Leaf Photosynthesis ◽  
Unit Leaf Area ◽  
Leaf Mass ◽  
Unit Leaf ◽  
Growth Variation

Technological advances during the past several decades have greatly enhanced our ability to measure leaf photosynthesis virtually anywhere and under any condition. Associated with the resulting proliferation of gas-exchange data is a lingering uncertainty regarding the importance of such measurements when it comes to explaining intrinsic causes of plant growth variation. Accordingly, in this paper we rely on a compilation of data to address the following questions: from both statistical and mechanistic standpoints, how closely does plant growth correlate with measures of leaf photosynthesis? Moreover, in this context, does the importance of leaf photosynthesis as an explanatory variable differ among growth light environments? Across a wide array of species and environments, relative growth rate (RGR) was positively correlated with daily integrals of photosynthesis expressed per unit leaf area (Aarea), leaf mass (Amass), and plant mass (Aplant). The amount of RGR variation explained by these relationships increased from 36% for the former to 93% for the latter. Notably, there was close agreement between observed RGR and that estimated from Aplant after adjustment for theoretical costs of tissue construction. Overall, based on an analysis of growth response coefficients (GRCs), gross assimilation rate (GAR), a photosynthesis-based estimate of biomass gain per unit leaf area, explained about as much growth variation as did leaf mass ratio (LMR) and specific leaf area (SLA). Further analysis of GRCs indicated that the importance of GAR in explaining growth variation increased with increasing light intensity. Clearly, when considered in combination with other key determinants, appropriate measures of leaf gas exchange effectively capture the fundamental role of leaf photosynthesis in plant growth variation.

scholarly journals Optimisation of photosynthetic carbon gain and within-canopy gradients of associated foliar traits for Amazon forest trees

2010 ◽  
Vol 7 (6) ◽  
pp. 1833-1859 ◽  
Author(s):  
J. Lloyd ◽  
S. Patiño ◽  
R. Q. Paiva ◽  
G. B. Nardoto ◽  
C. A. Quesada ◽  
...  
Keyword(s):  
Leaf Area ◽  
Amazon Basin ◽  
Photosynthetic Capacity ◽  
Carbon Gain ◽  
Amazon Forest ◽  
Forest Trees ◽  
Individual Tree ◽  
Unit Leaf Area ◽  
Unit Leaf ◽  
Tree Canopies

Abstract. Vertical profiles in leaf mass per unit leaf area (MA), foliar 13C composition (δ13C), nitrogen (N), phosphorus (P), carbon (C) and major cation concentrations were estimated for 204 rain forest trees growing in 57 sites across the Amazon Basin. Data was analysed using a multilevel modelling approach, allowing a separation of gradients within individual tree canopies (within-tree gradients) as opposed to stand level gradients occurring because of systematic differences occurring between different trees of different heights (between-tree gradients). Significant positive within-tree gradients (i.e. increasing values with increasing sampling height) were observed for MA and [C]DW (the subscript denoting on a dry weight basis) with negative within-tree gradients observed for δ13C, [Mg]DW and [K]DW. No significant within-tree gradients were observed for [N]DW, [P]DW or [Ca]DW. The magnitudes of between-tree gradients were not significantly different to the within-tree gradients for MA, δ13C, [C]DW, [K]DW, [N]DW, [P]DW and [Ca]DW. But for [Mg]DW, although there was no systematic difference observed between trees of different heights, strongly negative within-tree gradients were found to occur. When expressed on a leaf area basis (denoted by the subscript "A"), significant positive gradients were observed for [N]A, [P]A and [K]A both within and between trees, these being attributable to the positive intra- and between-tree gradients in MA mentioned above. No systematic within-tree gradient was observed for either [Ca]A or [Mg]A, but with a significant positive gradient observed for [Mg]A between trees (i.e. with taller trees tending to have a higher Mg per unit leaf area). Significant differences in within-tree gradients between individuals were observed only for MA, δ13C and [P] A. This was best associated with the overall average [P]A for each tree, this also being considered to be a surrogate for a tree's average leaf area based photosynthetic capacity, Amax. A new model is presented which is in agreement with the above observations. The model predicts that trees characterised by a low upper canopy Amax should have shallow, or even non-existent, within-canopy gradients in Amax, with optimal intra-canopy gradients becoming sharper as a tree's upper canopy Amax increases. Nevertheless, in all cases it is predicted that the optimal within-canopy gradient in Amax should be substantially less than for photon irradiance. Although this is also shown to be consistent with numerous observations as illustrated by a literature survey of gradients in photosynthetic capacity for broadleaf trees, it is also in contrast to previously held notions of optimality. A new equation relating gradients in photosynthetic capacity within broadleaf tree canopies to the photosynthetic capacity of their upper canopy leaves is presented.

Sign in / Sign up

Export Citation Format

Share Document