Leaf silicon accumulation rates in relation to light environment and shoot growth rates in paper mulberry (Broussonetia papyrifera, Moraceae)

We provide a comprehensive description and comparison of the various imaging and non-imaging-based techniques used to measure vegetative plant shoot growth and suggest a terminology for growth rates.

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Internal Phosphorus Flows During Development of Phosphorus Stress in Stylosanthes hamata

Functional Plant Biology ◽

10.1071/pp9900451 ◽

1990 ◽

Vol 17 (4) ◽

pp. 451 ◽

Cited By ~ 28

Author(s):

FW Smith ◽

WA Jackson ◽

PJV Berg

Keyword(s):

Root Growth ◽

Growth Rates ◽

Shoot Growth ◽

Phosphorus Content ◽

Phosphorus Deficiency ◽

Root Weight ◽

Maximal Growth ◽

Apparent Lack ◽

Phosphorus Stress ◽

Stylosanthes Hamata

Partitioning and net transfer of phosphorus between shoots and roots in the tropical forage legume Stylosanthes hamata cv. Verano during the development of phosphorus deficiency has been studied. Plants were stressed by either growing them in dilute flowing culture on continuously maintained external phosphorus concentrations that were inadequate for maximal growth, or by transferring plants of varying phosphorus status to phosphorus-free media. An external phosphorus concentration of 1 �M P was found to be just adequate for maximal growth of S. hamata. Phosphorus stress caused rapid and substantial increases in root weight percentage. It is proposed that this represents an important adaptive mechanism for maximising phosphorus uptake by S. hamata growing in phosphorus-deficient soils. Roots contained the minimum proportion of the plant's phosphorus content when root phosphorus concentrations were 8-10 �mol P g-1 root, and shoot phosphorus concentrations were 16-20 �mol P g-1 shoot. When tissue concentrations were less than these values, plants suffered from phosphorus stress and phosphorus was either preferentially retained by the roots or rapidly transferred from shoots to roots, reducing the growth rates of shoots, but permitting root growth to continue. Upon reducing the external phosphorus supply to plants whose root phosphorus concentrations exceeded 8 to 10 �mol P g-1 root, excess phosphorus was rapidly transferred from the root to the shoot to maintain shoot growth rates. The mobility of phospborus within the plant, and the apparent lack of any delay in transferring phosphorus from shoots to roots as phosphorus stress developed, represent another adaptive feature that is likely to be important to the successful growth of S. hamata in low phosphorus soils. When the phosphorus supply was limited, the plant's resources were directed toward maintaining root growth. Even extremely phosphorus deficient plants, in which shoot growth had ceased, maintained linear rates of root growth. These linear rates were related to the total phosphorus content of the plant. In the latter stages of phosphorus deprivation, linear rates of root growth were maintained by remobilisation of phosphorus from the older parts of the root system to sustain the phosphorus supply to the root meristems.

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Salinity tolerances of three succulent halophytes (Tecticornia spp.) differentially distributed along a salinity gradient

Functional Plant Biology ◽

10.1071/fp16025 ◽

2016 ◽

Vol 43 (8) ◽

pp. 739 ◽

Cited By ~ 7

Author(s):

Louis Moir-Barnetson ◽

Erik J. Veneklaas ◽

Timothy D. Colmer

Keyword(s):

Growth Rates ◽

Shoot Growth ◽

High Salinity ◽

Salt Lake ◽

Salinity Gradient ◽

Saline Soils ◽

Low Salinity ◽

Substrate Limitation ◽

Extreme Salinity ◽

Osmotic Potentials

We evaluated tolerances to salinity (10–2000 mM NaCl) in three halophytic succulent Tecticornia species that are differentially distributed along a salinity gradient at an ephemeral salt lake. The three species showed similar relative shoot and root growth rates at 10–1200 mM NaCl; at 2000 mM NaCl, T. indica subsp. bidens (Nees) K.A.Sheph and P.G.Wilson died, but T. medusa (K.A.Sheph and S.J.van Leeuwen) and T. auriculata (P.G.Wilson) K.A.Sheph and P.G.Wilson survived but showed highly diminished growth rates and were at incipient water stress. The mechanisms of salinity tolerance did not differ among the three species and involved the osmotic adjustment of succulent shoot tissues by the accumulation of Na+, Cl– and the compatible solute glycinebetaine, and the maintenance of high net K+ to Na+ selectivity to the shoot. Growth at extreme salinity was presumably limited by the capacity for vacuolar Na+ and Cl– uptake to provide sufficiently low tissue osmotic potentials for turgor-driven growth. Tissue sugar concentrations were not reduced at high salinity, suggesting that declines in growth would not have been caused by inadequate photosynthesis and substrate limitation compared with plants at low salinity. Equable salt tolerance among the three species up to 1200 mM NaCl means that other factors are likely to contribute to species composition at sites with salinities below this level. The lower NaCl tolerance threshold for survival in T. indica suggests that this species would be competitively inferior to T. medusa and T. auriculata in extremely saline soils.

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Establishment and Growth of Begonias in the Landscape as Affected by Root Ball Condition at Transplanting

Journal of Environmental Horticulture ◽

10.24266/0738-2898-24.4.213 ◽

2006 ◽

Vol 24 (4) ◽

pp. 213-217

Author(s):

S.M. Scheiber ◽

Richard C. Beeson

Keyword(s):

Growth Rates ◽

Biomass Accumulation ◽

Dry Mass ◽

The Other ◽

Total Biomass ◽

Accumulation Rates ◽

Bedding Plant ◽

Canopy Size ◽

Begonia Semperflorens

Abstract Begonias (Begonia semperflorens) were transplanted into an open-sided clear polyethylene covered shelter to evaluate the effect of root ball condition on establishment and growth. Three root ball classes were evaluated: non root-bound (NRB; 6 week old plants), root-bound (RB; 10 week old plants), and root-bound with the bottom 1 cm of the root ball removed (RBM). Non root-bound plants had greater growth rates for both height and faster rates of accumulation for cumulative root dry mass and new root dry mass relative to the other treatments tested. Cumulative shoot dry mass, new shoot dry mass, and total biomass accumulation rates were slower among RB plants compared to other rootball conditions. Mean canopy size, shoot dry mass, and biomass of NRB were significantly less at transplant; however all parameters were comparable among treatments 12 weeks later. Final mean shoot to root ratios were lower for the NRB treatment relative to RBM. Results indicate smaller, NRB transplants establish faster in the landscape. Furthermore, rootball manipulation is not recommended as it had no significant effect on root establishment or canopy growth of this annual bedding plant in the landscape.

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Effect of Cyclic Irrigation on Growth of Magnolias Produced Using Five In-ground Systems

Journal of Environmental Horticulture ◽

10.24266/0738-2898-21.3.148 ◽

2003 ◽

Vol 21 (3) ◽

pp. 148-152

Author(s):

R. C. Beeson ◽

K. Keller

Keyword(s):

Growth Rates ◽

Shoot Growth ◽

Similar Rate ◽

Height Growth ◽

Irrigation Event ◽

The Other ◽

Diameter Growth ◽

Trunk Diameter ◽

Magnolia Grandiflora ◽

Ground Systems

Abstract Five in-ground systems were evaluated based on shoot growth and marketability for the production of 2.17 m (7 ft) tall and 5.08 cm (2 in) trunk diameter Magnolia grandiflora cv. ‘Symmes Select’. Systems evaluated were Root Control Bags, Geo-Cell bags, and #25 containers in pot-in-pot in Experiment 1, and Agro-liners in socket pots and directly in-ground in Experiment 2. Each system was either cyclically irrigated or given a single irrigation event daily. In Experiment 1, cyclic irrigation increased the rate of height growth and trunk diameter compared to a single irrigation. Trees in Root Control Bags and pot-in-pot grew at a similar rate and faster than those in Geo-Cell bags. Faster growth rates with cyclic irrigation resulted in earlier marketability compared to single irrigation daily, except for pot-in-pot. In Experiment 2, cyclic irrigation increased the rate of trunk diameter growth, and Agro-liners in pots had greater height and trunk diameter growth rates than those directly in ground. Trees grown in the in-ground pot systems, whether in Agro-liners or black polyethylene containers, grew similarly to trees in Root Control Bags. Trees grown in Geo-cells or Agro-liners in-ground had significantly slower growth than the other treatments.

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Species and Their Relationships with Air and Soil Temperatures

HortTechnology ◽

10.21273/horttech.9.1.131 ◽

1999 ◽

Vol 9 (1) ◽

pp. 131

Author(s):

Timothy K. Broschat

Keyword(s):

Root Growth ◽

Growth Rates ◽

Shoot Growth ◽

Cocos Nucifera ◽

Primary Root ◽

The Other ◽

Date Palms ◽

Primary Roots ◽

Root And Shoot Growth ◽

Soil Temperatures

Royal palms [Roystonea regia (HBK.) O.F. Cook], coconut palms (Cocos nucifera L. `Malayan Dwarf'), queen palms [Syagrus romanzoffiana (Chamisso) Glassman], and pygmy date palms (Phoenix roebelenii O'Brien) were grown in a rhizotron to determine the patterns of root and shoot growth over a 2-year period. Roots and shoots of all four species of palms grew throughout the year, but both root and shoot growth rates were positively correlated with air and soil temperature for all but the pygmy date palms. Growth of primary roots in all four species was finite for these juvenile palms and lasted for only 5 weeks in royal palms, but ≈7 weeks in the other three species. Elongation of secondary roots lasted for only 9 weeks for coconut palms and less than half of that time for the other three species. Primary root growth rate varied from 16 mm·week-1 for coconut and pygmy date palms to 31 mm·week-1 for royal palms, while secondary root growth rates were close to 10 mm·week-1 for all species. About 25% of the total number of primary roots in these palms grew in contact with the rhizotron window, allowing the prediction of the total root number and length from the sample of roots visible in the rhizotron. Results indicated that there is no obvious season when palms should not be transplanted in southern Florida because of root inactivity.

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Effect of mechanical impedance on root and shoot growth of rice at time intervals

Dhaka University Journal of Biological Sciences ◽

10.3329/dujbs.v19i2.8953 ◽

1970 ◽

Vol 19 (2) ◽

pp. 119-128

Author(s):

AHMZ Ali

Keyword(s):

Root Growth ◽

Growth Rates ◽

Shoot Growth ◽

Leaf Growth ◽

Mechanical Impedance ◽

Growth Time ◽

Time Interval ◽

Night Time ◽

Time Intervals ◽

Root And Shoot Growth

In a phytotron chamber the effect of mechanical impedance on root and shoot growth of BR?29 variety of rice at different time intervals reaveled that length of the seminal axis and length of the longest leaf extended linearly in both unimpeded and impeded treatments. Diameter of roots increased in impeded treatment. The number of first order laterals also increased linearly with time in both unimpeded and impeded treatments. Although there were always significantly more laterals on the unimpeded root axes, lateral spacing does not show any tendency to change with time. Root growth rate was nearly half in impeded than in unimpeded treatment. The pattern of root length in unimpeded (UI) did not differ from that of the pattern in impeded (I) treatment as the ratios (I/UI) were more or less constant with time. The time of leaf appearance was delayed by one ? two days and leaf growth period was shortened by one day in impeded than in unimpeded treatment. Leaf growth rates did not differ significantly between day and night time although night time growth rates were always slightly less than day time. Key words: Mechanical impedance; Pattern of root growth; Time interval; Shoot growth; Rice DOI: http://dx.doi.org/10.3329/dujbs.v19i2.8953 DUJBS 2010; 19(2): 119-128

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Interrelationship of Nitrogen and Light on Episodic Growth of Ligustrum japonicum

Journal of Environmental Horticulture ◽

10.24266/0738-2898-12.1.43 ◽

1994 ◽

Vol 12 (1) ◽

pp. 43-46

Author(s):

Jeff S. Kuehny ◽

Dennis R. Decoteau

Keyword(s):

Growth Rate ◽

Root Growth ◽

Relative Growth Rate ◽

Growth Rates ◽

Shoot Growth ◽

Fertilizer Application ◽

Relative Growth ◽

Mature Leaves ◽

Episodic Growth ◽

Ligustrum Japonicum

Abstract Exclusion of nitrogen and light from existing leaves at initiation of an episode of shoot growth decreased shoot and root relative growth rate. The combination of both nitrogen and light exclusion synergistically impacted relative growth rate for shoot (RGRs) and relative growth rate for root (RGRr). The next episode of shoot growth provided sufficient leaf area for carbohydrate assimilation and maintaining shoot and root growth rates when light was excluded from mature leaves. A better understanding of the developmental and biochemical changes of this episodic species provided useful information for timing of fertilizer application and transplanting of Ligustrum and other episodic species.

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Variability in the growth rates and foliage δ15N values of black spruce trees across a slope gradient in the Alaskan Interior

Canadian Journal of Forest Research ◽

10.1139/cjfr-2015-0469 ◽

2016 ◽

Vol 46 (12) ◽

pp. 1483-1490 ◽

Cited By ~ 3

Author(s):

Ayumi Tanaka-Oda ◽

Tanaka Kenzo ◽

Jumpei Toriyama ◽

Yojiro Matsuura

Keyword(s):

Tree Growth ◽

Growth Rates ◽

Shoot Growth ◽

Black Spruce ◽

N Uptake ◽

Slope Gradient ◽

Mycorrhizal Associations ◽

High Elevations ◽

Lower Slope ◽

Upper Slope

Black spruce (Picea mariana (Mill.) B.S.P.) is a dominant species on north-facing slopes located on the permafrost in the Alaskan Interior, where tree growth rates vary significantly across slope gradients. To better understand the effects of nitrogen (N) and mycorrhizal associations on plant growth, we investigated the relationships between tree growth and isotope ratios of nitrogen (δ15N) in foliage and roots, because plant δ15N values reflect tree dependencies on N uptake by mycorrhizae. We established two transects (one along a slope gradient, and a second on a north-to-east axis at a fixed elevation) and four plots on the slope gradient transect. We measured current shoot growth of saplings on transects and aboveground biomass (AGB) in the plots. We collected foliage and fine root samples and measured their δ15N signatures and N concentrations. The AGB and shoot growth varied widely across the gradient: values were higher at high elevations and at the east–northeast aspect. Foliage δ15N values and N concentrations were positively correlated with tree growth, but growth rate was negatively correlated with the dependency on mycorrhizae for N uptake. Thus, black spruce had a reduced dependency on mycorrhizae for N uptake on the upper slope, where conditions were N-rich. On the lower slope, where the soil active layer was shallow, black spruce growth was limited and had an elevated dependency on mycorrhizae for N uptake.

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Seasonal and Clonal Differences in Shoot Extension Rates and Numbers in Tea (Camellia sinensis)

Experimental Agriculture ◽

10.1017/s001447970001543x ◽

1990 ◽

Vol 26 (1) ◽

pp. 83-98 ◽

Cited By ~ 24

Author(s):

William Stephens ◽

M. K. V. Carr

Keyword(s):

Camellia Sinensis ◽

Growth Rates ◽

Selection Criteria ◽

Shoot Growth ◽

Clonal Selection ◽

Measurement Techniques ◽

Clonal Variation ◽

Population Densities ◽

Selection Technique ◽

Dominant Component

SUMMARYShoot extension rates and numbers recorded over an 18 month period in Tanzania from three contrasting clones were analysed to determine variation between and within seasons. Clonal differences in base temperatures for shoot extension ranged from 10.3 to 14.5°C, whilst variability in the response of shoot growth rates to temperature could be ascribed to the shoot selection technique employed. Considerable clonal variation in shoot population densities occurred, with maxima ranging from 200 to 1200 shoots m−2. Total active shoot extension, the product of shoot growth rates and population densities, varied between 4 and 35 m m−2 week−1, shoot numbers being the dominant component. The implications of these results are discussed in terms of shoot measurement techniques, clonal selection criteria, yield modelling and harvesting policies.

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