Interactive effects of lateral shade and wind on stem allometry, biomass allocation, and mechanical stability in Abutilon theophrasti (Malvaceae)

Abstract Aims Biomass allocation to different organs is a fundamental plant ecophysiological process to better respond to changing environments; yet, it remains poorly understood how patterns of biomass allocation respond to nitrogen (N) additions across terrestrial ecosystems worldwide. Methods We conducted a meta-analysis using 5474 pairwise observations from 333 articles to assess how N addition affected plant biomass and biomass allocation among different organs. We also tested the “ratio-based optimal partitioning” vs. the “isometric allocation” hypotheses to explain potential N addition effects on biomass allocation. Important findings We found that (1) N addition significantly increased whole plant biomass and the biomass of different organs, but decreased root:shoot ratio (RS) and root mass fraction (RMF) while no effects of N addition on leaf mass fraction (LMF) and stem mass fraction (SMF) at the global scale; (2) the effects of N addition on ratio-based biomass allocation were mediated by individual or interactive effects of moderator variables such as experimental conditions, plant functional types, latitudes, and rates of N addition; and (3) N addition did not affect allometric relationships among different organs, suggesting that decreases in RS and RMF may result from isometric allocation patterns following increases in whole plant biomass. Despite alteration of ratio-based biomass allocation between root and shoot by N addition, the unaffected allometric scaling relationships among different organs (including root vs. shoot) suggest that plant biomass allocation patterns are more appropriately explained by the isometric allocation hypothesis rather than the optimal partitioning hypothesis. Our findings contribute to better understand N-induced effects on allometric relationships of terrestrial plants, and suggest that these ecophysiological responses should be incorporated into models that aim to predict how terrestrial ecosystems may respond to enhanced N deposition under future global change scenarios.

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Ozone-Herbicide Interactions on Sorghum (Sorghum bicolor) and Velvetleaf (Abutilon theophrasti) Seedlings

Weed Science ◽

10.1017/s0043174500070879 ◽

1983 ◽

Vol 31 (6) ◽

pp. 857-861 ◽

Cited By ~ 3

Author(s):

Kriton K. Hatzios ◽

Yaw-Shing Yang

Keyword(s):

Sorghum Bicolor ◽

Dry Weight ◽

Abutilon Theophrasti ◽

Air Pollutant ◽

Interactive Effects ◽

Herbicide Treatment

The potential interactive effects between the herbicides chlorsulfuron {2-chloro-N-[[(4-methoxy-6-methyl-1,3,5-triazin-2-yl)amino]carbonyl] benzenesulfonamide}, PP009 {butyl 2-[4-[5-(trifluoromethyl-2-pyridinyl) oxy] phenoxy] propanoate}, and BAS 9052 OH {2-[1-(ethoxyimino)-butyl]-5-[2-(ethylthio)-propyl]-3-hydroxy-2-cyclohexene-one} and the air pollutant ozone (O3) on the growth of sorghum [Sorghum bicolor(L.) Moench. ‘Funk G623rg’] and velvetleaf (Abutilon theophrastiMedic. # ABUTH) were examined. All three herbicides were applied postemergence either before or after a single 6-h fumigation of sorghum and velvetleaf seedlings with O3at 0, 0.1, and 0.2 ppmv. Chlorsulfuron was applied at 0, 0.06, or 0.12 kg ai/ha, while PP009 and BAS 9052 OH were applied at 0, 0.6, and 1.2 kg ai/ha. Two weeks after treatment, dry weight responses of velvetleaf seedlings revealed that PP009 interacted synergistically while chlorsulfuron and BAS 9052 OH interacted antagonistically with O3. The sequence of O3fumigation and herbicide treatment appeared to be an important factor determining the type of interactive effects of these herbicides with O3. The interactive effects of all three herbicides with O3on sorghum seedlings were additive regardless of the sequence of O3fumigation and herbicide treatment.

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EFFECTS OF ROOT DEFORMATION AND LIGHT AVAILABILITY ON GROWTH AND BIOMASS ALLOCATION OF Senna multijuga SEEDLINGS (Rich) H. S. Irwin & Barneby

Revista Árvore ◽

10.1590/1806-908820200000018 ◽

2020 ◽

Vol 44 ◽

Author(s):

Emile Caroline Silva Lopes ◽

Ândrea Carla Dalmolin ◽

Ivan Bezerra Allama ◽

Karine Ferreira Pereira ◽

William Martin Aitken II ◽

...

Keyword(s):

Biomass Allocation ◽

Growth Rates ◽

Forest Restoration ◽

Light Availability ◽

Tropical Tree ◽

Interactive Effects ◽

Low Light ◽

Relative Growth ◽

Root Deformation ◽

Senna Multijuga

ABSTRACT The effects of root deformation caused by errors in the pricking-out process in forest nurseries are still unknown for tropical tree seedlings. We analyzed the effects of light availability and root deformation on growth and biomass allocation in seedlings of Senna multijuga, a pioneer tropical tree commonly used in forest restoration programs. Our hypotheses were: (a) as a typical light-demanding species, the seedlings of S. multijuga may have their growth compromised by low light availability; (b) root deformation impairs growth rates and induces changes in biomass allocation; and (c) the effects of low light availability on growth and biomass allocation are increased by root deformation. Seedlings with and without root deformation were cultivated for 43 days under three levels of total daily photosynthetically active radiation (PAR) (28, 12, and 1 mol photons m-2 day-1). Seedlings of S. multijuga had their growth rates severely affected by values of PAR at about 1 mol photons m-2 day-1, but root deformation did not affect the relative growth rates of the whole plant. Instead, root deformation caused a decrease in the relative growth rate of roots in all light availabilities. The changes in root growth affected biomass allocation to the roots. The interactive effects of light availability and root deformation on the allocation of biomass to leaves are more pronounced at low light availability. Root deformations may lead to the production of seedlings with a low competitiveness capacity regardless of light conditions.

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Stage-dependent plasticity in biomass allocation and allometry in response to population density in Abutilon theophrasti: a step forward to understanding the nature of phenotypic plasticity

Plant Ecology ◽

10.1007/s11258-021-01168-8 ◽

2021 ◽

Author(s):

Shu Wang ◽

Dao-Wei Zhou

Keyword(s):

Phenotypic Plasticity ◽

Population Density ◽

Biomass Allocation ◽

Abutilon Theophrasti ◽

Dependent Plasticity

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An improved design for an Scanning Tunnelling Microscope (STM) for use in a Transmission Electron Microscope (TEM)

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100086222 ◽

1991 ◽

Vol 49 ◽

pp. 384-385

Author(s):

W.K. Lo ◽

J.C.H. Spence

Keyword(s):

Electron Microscope ◽

Transmission Electron Microscope ◽

Mechanical Stability ◽

Scanning Tunnelling Microscope ◽

Reflection Mode ◽

Specimen Holder ◽

Transmission Electron ◽

Scanning Tunnelling ◽

Improved Design

An improved design for a combination Scanning Tunnelling Microscope/TEM specimen holder is presented. It is based on earlier versions which have been used to test the usefulness of such a device. As with the earlier versions, this holder is meant to replace the standard double-tilt specimen holder of an unmodified Philips 400T TEM. It allows the sample to be imaged simultaneously by both the STM and the TEM when the TEM is operated in the reflection mode (see figure 1).The resolution of a STM is determined by its tip radii as well as its stability. This places strict limitations on the mechanical stability of the tip with respect to the sample. In this STM the piezoelectric tube scanner is rigidly mounted inside the endcap of the STM holder. The tip coarse approach to the sample (z-direction) is provided by an Inchworm which is located outside the TEM vacuum.

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Experiments with a scanning tunneling microscope (STM) mounted in a scanning electron microscope (SEM)

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100144620 ◽

1986 ◽

Vol 44 ◽

pp. 636-639

Author(s):

Oliver C. Wells ◽

Mark E. Welland

Keyword(s):

Electron Microscope ◽

Scanning Electron Microscope ◽

Mechanical Stability ◽

Tunneling Current ◽

Feedback System ◽

Scanning Tunneling ◽

Surface Profiling ◽

Close Proximity ◽

Metal Tip ◽

Scanning Electron

Scanning tunneling microscopes (STM) exist in two versions. In both of these, a pointed metal tip is scanned in close proximity to the specimen surface by means of three piezos. The distance of the tip from the sample is controlled by a feedback system to give a constant tunneling current between the tip and the sample. In the low-end STM, the system has a mechanical stability and a noise level to give a vertical resolution of between 0.1 nm and 1.0 nm. The atomic resolution STM can show individual atoms on the surface of the specimen.A low-end STM has been put into the specimen chamber of a scanning electron microscope (SEM). The first objective was to investigate technological problems such as surface profiling. The second objective was for exploratory studies. This second objective has already been achieved by showing that the STM can be used to study trapping sites in SiO2.

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