Response to Phosphorus Availability during Vegetative and Reproductive Growth of Chrysanthemum: I. Whole-plant Carbon Dioxide Exchange

Whole-plant CO2 exchange and root-shoot interactions during transition from vegetative to reproductive growth of `Coral Charm' chrysanthemum (Dendranthema ×grandiflorum Ramat.) were investigated over a range of P concentrations considered to be deficient (1 μM), adequate (100 μM), or high (5 mM). Transition from vegetative to reproductive growth resulted in reduced photosynthate production, root respiration, biomass accumulation, and starch accumulation in leaves. Root respiration was low in high-P plants regardless of growth stage. Reduced root respiration may indicate changes in source-sink relationships during the transition from vegetative to reproductive growth, making roots less competitive sinks than developing flowers. Plant responses to P deficiency included decreased CO2 assimilation and shoot biomass accumulation but increased root respiration, root:shoot ratio, specific leaf mass (SLM), and starch accumulation in leaves. Reduced root respiration activity in high-P plants was presumably due to differences in root architecture resulting in proportionately fewer root apices in high P. Daily CO2 assimilation, shoot biomass, SLM, and root:shoot ratio were similar in plants grown with adequate-P and high-P availability, although plant P accumulation increased with P availability. Our results suggest that the excessive P fertilization often used in ornamental production systems is detrimental to root activity.

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Response to Phosphorus Availability during Vegetative and Reproductive Growth of Chrysanthemum: II. Biomass and Phosphorus Dynamics

Journal of the American Society for Horticultural Science ◽

10.21273/jashs.123.2.223 ◽

1998 ◽

Vol 123 (2) ◽

pp. 223-229 ◽

Cited By ~ 11

Author(s):

Conny W. Hansen ◽

Jonathan Lynch

Keyword(s):

Growth Rate ◽

Root Growth ◽

Production Rate ◽

Root Length ◽

Shoot Growth ◽

Biomass Accumulation ◽

Shoot Biomass ◽

Reproductive Growth ◽

Relative Growth ◽

Whole Plant

Whole-plant biomass accumulation, P dynamics, and root-shoot interactions during transition from vegetative to reproductive growth of `Coral Charm' chrysanthemum (Dendranthema ×grandiflorum Ramat.) (Zander, 1993) were investigated over a range of P concentrations considered to be deficient (1 μm), adequate (100 μm), and high (5 mm). In nondeficient plants, transition from vegetative to reproductive growth resulted in reduced relative growth rate and root and shoot biomass accumulation. Reproductive plants showed a higher commitment of the whole plant to the production of developing flowers than to leaves and roots, whereas, in vegetative plants, the highest component production rate was in leaves. This indicates changes in the source-sink relationships during transition from vegetative growth making developing flowers stronger sinks for photoassimilates than roots. Phosphorus allocated to developing flowers was predominantly lost from leaves. Phosphorus-deficient plants showed characteristic P-deficiency symptoms and favored root growth over shoot growth regardless of growth stage. Phosphorus availability in nondeficient plants affected root growth more than shoot growth. No substantial differences in shoot biomass production, relative growth rate, and CO2 assimilation rates were observed in adequate-P and high-P plants. However, the root component production rate, root to shoot ratio, root length ratio, specific root length, specific root area, root mass to leaf area ratio, and root respiration increased in adequate-P plants compared with high-P plants, which indicates that high root activity was maintained without affecting shoot biomass in buffered P conditions. Our results suggest that the high P concentrations used in many horticultural systems may have no benefit in terms of shoot growth and may actually be detrimental to root growth.

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Morphological and Metabolite Responses of Potatoes under Various Phosphorus Levels and Their Amelioration by Plant Growth-Promoting Rhizobacteria

International Journal of Molecular Sciences ◽

10.3390/ijms22105162 ◽

2021 ◽

Vol 22 (10) ◽

pp. 5162

Author(s):

Leangsrun Chea ◽

Birgit Pfeiffer ◽

Dominik Schneider ◽

Rolf Daniel ◽

Elke Pawelzik ◽

...

Keyword(s):

Amino Acids ◽

Plant Growth ◽

Plant Growth Promoting Rhizobacteria ◽

Shoot Biomass ◽

Root Surface Area ◽

Limiting Factor ◽

P Availability ◽

P Deficiency ◽

Plant Growth Promoting ◽

Growth Promoting

Low phosphorus (P) availability is a major limiting factor for potatoes. P fertilizer is applied to enhance P availability; however, it may become toxic when plants accumulate at high concentrations. Therefore, it is necessary to gain more knowledge of the morphological and biochemical processes associated with P deficiency and toxicity for potatoes, as well as to explore an alternative approach to ameliorate the P deficiency condition. A comprehensive study was conducted (I) to assess plant morphology, mineral allocation, and metabolites of potatoes in response to P deficiency and toxicity; and (II) to evaluate the potency of plant growth-promoting rhizobacteria (PGPR) in improving plant biomass, P uptake, and metabolites at low P levels. The results revealed a reduction in plant height and biomass 60–80% under P deficiency compared to P optimum. P deficiency and toxicity conditions also altered the mineral concentration and allocation in plants due to nutrient imbalance. The stress induced by both P deficiency and toxicity was evident from an accumulation of proline and total free amino acids in young leaves and roots. Furthermore, root metabolite profiling revealed that P deficiency reduced sugars by 50–80% and organic acids by 20–90%, but increased amino acids by 1.5–14.8 times. However, the effect of P toxicity on metabolic changes in roots was less pronounced. Under P deficiency, PGPR significantly improved the root and shoot biomass, total root length, and root surface area by 32–45%. This finding suggests the potency of PGPR inoculation to increase potato plant tolerance under P deficiency.

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Phosphorus Application Improves the Cotton Yield by Enhancing Reproductive Organ Biomass and Nutrient Accumulation in Two Cotton Cultivars with Different Phosphorus Sensitivity

Agronomy ◽

10.3390/agronomy10020153 ◽

2020 ◽

Vol 10 (2) ◽

pp. 153

Author(s):

Babar Iqbal ◽

Fanxuan Kong ◽

Inam Ullah ◽

Saif Ali ◽

Huijie Li ◽

...

Keyword(s):

Biomass Accumulation ◽

Reproductive Organ ◽

Growth And Yield ◽

P Availability ◽

Nutrient Accumulation ◽

Cotton Yield ◽

Reproductive Growth ◽

P Rate ◽

Reproductive Biomass ◽

Phosphorus Application

Phosphorus (P) plays a pivotal role in cotton by enhancing the reproductive growth and yield formation. Cotton cultivars vary greatly in response to P availability, especially under P-deficient conditions. So, we hypothesized that the increasing P level promotes the reproductive growth in cotton cultivars varying with P sensitivity. For this, two cotton cultivars, Lu-54 (sensitive to low P) and Yuzaomian-9110 (tolerant to low P), in response to three different P levels (P0: 0 (control), P1: 100, and P2: 200 kg P2O5 ha−1) were studied at 39, 52, 69, 83, and 99 days after transplanting during 2017 and 2018. The results revealed that the seed cotton yield was improved in P1 and P2 treatments by 23.9%–34.5% and 30.8%–52.3% in Lu-54, and 16.6%–25.6% and 20.6%–38.5% in Yuzaomian-9110 during 2017 and 2018, respectively. The accumulation of reproductive organ biomass was 21.0%–52.1% and 28.5%–56.8% higher in Lu-54 and 24.2%–56.8% and 34.8%–69.1% higher in Yuzaomian-9110 in P1 and P2 over the control, respectively. During the fast accumulation period, the average accumulation of N, P, K, and biomass across the years in P2 were recorded as 0.75, 0.6, 0.5, and 120.5 kg ha−1 d−1 in Lu-54, while they were 0.65, 0.5, 0.8, and 98.5 kg ha−1 d−1 in Yuzaomian-9110. Overall, a longer period, in terms of reproductive biomass accumulation, was recorded for Yuzaomian-9110 compared with Lu-54 in 2017 and vice versa across the 2018 growing season. The results suggested that increasing P rate improved yield, reproductive organ biomass, as well as nutrient accumulation in both cotton cultivars. However, low P-sensitive cultivar (Lu-54) was more responsive to P application compared with low P-tolerant cultivar.

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Sex-specifically responsive strategies to phosphorus availability combined with different soil nitrogen forms in dioecious Populus cathayana

Journal of Plant Ecology ◽

10.1093/jpe/rtab025 ◽

2021 ◽

Author(s):

Xiucheng Liu ◽

Yuting Wang ◽

Shuangri Liu ◽

Miao Liu

Keyword(s):

Root Length ◽

Root Length Density ◽

Specific Root Length ◽

P Uptake ◽

Root Tip ◽

P Availability ◽

P Deficiency ◽

Populus Cathayana ◽

Leaf P ◽

P Supply

Abstract Aims Phosphorus (P) availability and efficiency are especially important for plant growth and productivity. However, the sex-specific P acquisition and utilization strategies of dioecious plant species under different N forms are not clear. Methods This study investigated the responsive mechanisms of dioecious Populus cathayana females and males based on P uptake and allocation to soil P supply under N deficiency, nitrate (NO3 −) and ammonium (NH4 +) supply. Important Findings Females had a greater biomass, root length density (RLD), specific root length (SRL) and shoot P concentration than males under normal P availability with two N supplies. NH4 + supply led to higher total root length, RLD and SRL but lower root tip number than NO3 − supply under normal P supply. Under P deficiency, males showed a smaller root system but greater photosynthetic P availability and higher leaf P remobilization, exhibiting a better capacity to adaptation to P-deficiency than females. Under P deficiency, NO3 − supply increased leaf photosynthesis and PUE but reduced RLD and SRL in females while males had higher leaf P redistribution and photosynthetic PUE than NH4 + supply. Females had a better potentiality to cope with P deficiency under NO3 − supply than NH4 + supply; the contrary was true for males. These results suggest that females may devote to increase in P uptake and shoot P allocation under normal P availability, especially under NO3 − supply, while males adopt more efficient resource use and P remobilization to maximum their tolerance to P-deficiency.

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Semiarid bunchgrasses accumulate molybdenum on alkaline copper mine tailings: assessing phytostabilization in the greenhouse

SN Applied Sciences ◽

10.1007/s42452-021-04732-z ◽

2021 ◽

Vol 3 (8) ◽

Author(s):

Paul M. Antonelli ◽

Matthew G. Coghill ◽

Wendy C. Gardner ◽

Lauchlan H. Fraser

Keyword(s):

Mine Tailings ◽

Soil Amendments ◽

Block Design ◽

Wood Chip ◽

Biomass Accumulation ◽

Shoot Biomass ◽

Tissue Samples ◽

Copper Mine ◽

Copper Mine Tailings ◽

Randomized Complete Block Design

AbstractPhytostabilization is the use of plants and soil amendments to physically stabilize and remediate contaminated mine wastes and to control wind and water erosion in semiarid environments. The aim of this study was to evaluate two native bunchgrass species’ (Pseudoroegneria spicata and Festuca campestris) biomass accumulation and metals uptake response to locally available soil amendments (compost, wood ash and wood chips) to determine their suitability for phytostabilization at an alkaline copper mine tailings site in British Columbia, Canada. In the greenhouse, bunchgrasses important as forage for livestock and wildlife were grown in tailings with various ash–compost–wood chip combinations and evaluated using a randomized complete block design with 13 treatments and 10 replicates. Plants were harvested after 90 d, and tissues were analyzed for root and shoot biomass. Tissue samples (n = 3) from three treatment subsets (ash, compost, blend) were selected for elemental analysis. Biomass increased with increasing compost applications, and the response was greatest for P. spicata. Shoot molybdenum exceeded the maximum tolerable level for cattle and was significantly higher when grasses were grown on the ash treatment (183–202 mg kg−1) compared to the others (19.7–58.3 mg kg−1). Translocation and root bioconcentration factors were highest on the ash treatment (2.53–12.5 and 1.75–7.96, respectively) compared to the other treatments (0.41–3.43 and 1.47–4.79, respectively) and indicate that both species are ‘accumulators.’ The findings suggest that these bunchgrasses were not ideal candidates for phytostabilization due to high shoot tissue molybdenum accumulation, but provide important considerations for mine restoration in semiarid grassland systems.

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Potassium Fertilization Stimulates Sucrose-to-Starch Conversion and Root Formation in Sweet Potato (Ipomoea batatas (L.) Lam.)

International Journal of Molecular Sciences ◽

10.3390/ijms22094826 ◽

2021 ◽

Vol 22 (9) ◽

pp. 4826

Author(s):

Yang Gao ◽

Zhonghou Tang ◽

Houqiang Xia ◽

Minfei Sheng ◽

Ming Liu ◽

...

Keyword(s):

Sweet Potato ◽

Ipomoea Batatas ◽

Intercellular Co2 Concentration ◽

Biomass Accumulation ◽

Starch Accumulation ◽

Storage Root ◽

Root Yield ◽

Starch Conversion ◽

And Storage ◽

Low K

A field experiment was established to study sweet potato growth, starch dynamic accumulation, key enzymes and gene transcription in the sucrose-to-starch conversion and their relationships under six K2O rates using Ningzishu 1 (sensitive to low-K) and Xushu 32 (tolerant to low-K). The results indicated that K application significantly improved the biomass accumulation of plant and storage root, although treatments at high levels of K, i.e., 300–375 kg K2O ha−1, significantly decreased plant biomass and storage root yield. Compared with the no-K treatment, K application enhanced the biomass accumulation of plant and storage root by 3–47% and 13–45%, respectively, through promoting the biomass accumulation rate. Additionally, K application also enhanced the photosynthetic capacity of sweet potato. In this study, low stomatal conductance and net photosynthetic rate (Pn) accompanied with decreased intercellular CO2 concentration were observed in the no-K treatment at 35 DAT, indicating that Pn was reduced mainly due to stomatal limitation; at 55 DAT, reduced Pn in the no-K treatment was caused by non-stomatal factors. Compared with the no-K treatment, the content of sucrose, amylose and amylopectin decreased by 9–34%, 9–23% and 6–19%, respectively, but starch accumulation increased by 11–21% under K supply. The activities of sucrose synthetase (SuSy), adenosine-diphosphate-glucose pyrophosphorylase (AGPase), starch synthase (SSS) and the transcription of Susy, AGP, SSS34 and SSS67 were enhanced by K application and had positive relationships with starch accumulation. Therefore, K application promoted starch accumulation and storage root yield through regulating the activities and genes transcription of SuSy, AGPase and SSS in the sucrose-to-starch conversion.

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Cultivar-Dependent Responses in Plant Growth, Leaf Physiology, Phosphorus Use Efficiency, and Tuber Quality of Potatoes Under Limited Phosphorus Availability Conditions

Frontiers in Plant Science ◽

10.3389/fpls.2021.723862 ◽

2021 ◽

Vol 12 ◽

Author(s):

Leangsrun Chea ◽

Ana Meijide ◽

Catharina Meinen ◽

Elke Pawelzik ◽

Marcel Naumann

Keyword(s):

Tuber Yield ◽

Plant Biomass ◽

P Uptake ◽

Tuber Quality ◽

P Availability ◽

Plant Tolerance ◽

P Deficiency ◽

Leaf Physiology ◽

Use Efficiency

The limited availability of phosphorus (P) in soils causes a major constraint in the productivity of potatoes, which requires increased knowledge of plant adaptation responses in this condition. In this study, six potato cultivars, namely, Agria, Lady Claire, Milva, Lilly, Sieglinde, and Verdi, were assessed for their responses on plant growth, leaf physiology, P use efficiency (PUE), and tuber quality with three P levels (Plow, Pmed, and Phigh). The results reveal a significant variation in the cultivars in response to different P availabilities. P-efficient cultivars, Agria, Milva, and Lilly, possessed substantial plant biomass, tuber yield, and high P uptake efficiency (PUpE) under low P supply conditions. The P-inefficient cultivars, Lady Claire, Sieglinde, and Verdi, could not produce tubers under P deprivation conditions, as well as the ability to efficiently uptake P under low-level conditions, but they were efficient in P uptake under high soil P conditions. Improved PUpE is important for plant tolerance with limited P availability, which results in the efficient use of the applied P. At the leaf level, increased accumulations of nitrate, sulfate, sucrose, and proline are necessary for a plant to acclimate to P deficiency-induced stress and to mobilize leaf inorganic phosphate to increase internal PUE and photosynthesis. The reduction in plant biomass and tuber yield under P-deficient conditions could be caused by reduced CO2 assimilation. Furthermore, P deficiency significantly reduced tuber yield, dry matter, and starch concentration in Agria, Milva, and Lilly. However, contents of tuber protein, sugars, and minerals, as well as antioxidant capacity, were enhanced under these conditions in these cultivars. These results highlight the important traits contributing to potato plant tolerance under P-deficient conditions and indicate an opportunity to improve the P efficiency and tuber quality of potatoes under deficient conditions using more efficient cultivars. Future research to evaluate molecular mechanisms related to P and sucrose translocation, and minimize tuber yield reduction under limited P availability conditions is necessary.

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Contribution of Arbuscular Mycorrhizal Fungi, Phosphate–Solubilizing Bacteria, and Silicon to P Uptake by Plant

Frontiers in Plant Science ◽

10.3389/fpls.2021.699618 ◽

2021 ◽

Vol 12 ◽

Author(s):

Hassan Etesami ◽

Byoung Ryong Jeong ◽

Bernard R. Glick

Keyword(s):

Arbuscular Mycorrhizal Fungi ◽

Mycorrhizal Fungi ◽

Crop Production ◽

Current Knowledge ◽

Arbuscular Mycorrhizal ◽

P Availability ◽

Phosphate Solubilizing Bacteria ◽

P Deficiency ◽

Phosphate Solubilizing ◽

P Fertilizers

Phosphorus (P) availability is usually low in soils around the globe. Most soils have a deficiency of available P; if they are not fertilized, they will not be able to satisfy the P requirement of plants. P fertilization is generally recommended to manage soil P deficiency; however, the low efficacy of P fertilizers in acidic and in calcareous soils restricts P availability. Moreover, the overuse of P fertilizers is a cause of significant environmental concerns. However, the use of arbuscular mycorrhizal fungi (AMF), phosphate–solubilizing bacteria (PSB), and the addition of silicon (Si) are effective and economical ways to improve the availability and efficacy of P. In this review the contributions of Si, PSB, and AMF in improving the P availability is discussed. Based on what is known about them, the combined strategy of using Si along with AMF and PSB may be highly useful in improving the P availability and as a result, its uptake by plants compared to using either of them alone. A better understanding how the two microorganism groups and Si interact is crucial to preserving soil fertility and improving the economic and environmental sustainability of crop production in P deficient soils. This review summarizes and discusses the current knowledge concerning the interactions among AMF, PSB, and Si in enhancing P availability and its uptake by plants in sustainable agriculture.

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Whole-plant Response of Six Poinsettia Cultivars to Three Fertilizer and Two Irrigation Regimes

Journal of the American Society for Horticultural Science ◽

10.21273/jashs.121.1.69 ◽

1996 ◽

Vol 121 (1) ◽

pp. 69-76 ◽

Cited By ~ 2

Author(s):

Ursula Schuch ◽

Richard A. Redak ◽

James Bethke

Keyword(s):

Leaf Area ◽

Chlorophyll Content ◽

Dry Weight ◽

Shoot Biomass ◽

Vegetative Development ◽

Chlorophyll Contents ◽

Shoot Dry Weight ◽

Irrigation Regimes ◽

Whole Plant ◽

Leaf N

Six cultivars of poinsettia (Euphorbia pulcherrima Wind.), `Angelika White', `Celebrate 2', `Freedom Red', `Lilo Red', `Red Sails', and `Supjibi Red' were grown for 9 weeks during vegetative development under three constant-feed fertilizer treatments, 80,160, or 240 mg N/liter and two irrigation regimes, well-watered (high irrigation) or water deficient (low irrigation). Plants fertilized with 80 or 240 mg N/liter were 10% to 18% shorter, while those fertilized with 160 mg N/liter were 25 % shorter with low versus high irrigation. Leaf area and leaf dry weight increased linearly in response to increasing fertilizer concentrations. Low irrigation reduced leaf area, leaf, stem, and shoot dry weight 3670 to 41%. Cultivars responded similarly to irrigation and fertilizer treatments in all components of shoot biomass production and no interactions between the main effects and cultivars occurred. Stomatal conductance and transpiration decreased with increasing fertilizer rates or sometimes with low irrigation. Highest chlorophyll contents occurred in leaves of `Lilo Red' and `Freedom Red'. Leaves of plants fertilized with 80 mg N/liter were deficient in leaf N and had 40 % to 49 % lower leaf chlorophyll content compared to plants fertilized with 160 or 240 mg N/liter. Irrigation had no effect on leaf N or chlorophyll content. At the end of the experiment leaves of `Supjibi Red' and `Angelika White' contained higher concentrations of soluble proteins than the other four cultivars.

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Water and phosphorus uptake by upland rice root systems unraveled under multiple scenarios: linking a 3D soil-root model and data

10.1101/2020.01.27.921247 ◽

2020 ◽

Author(s):

Trung Hieu Mai ◽

Pieterjan De Bauw ◽

Andrea Schnepf ◽

Roel Merckx ◽

Erik Smolders ◽

...

Keyword(s):

Upland Rice ◽

Phosphorus Uptake ◽

Root Systems ◽

Multiscale Model ◽

P Uptake ◽

Water Dynamics ◽

Small Scale ◽

P Availability ◽

P Deficiency ◽

Plant P Uptake

AbstractBackground and aimsUpland rice is often grown where water and phosphorus (P) are limited and these two factors interact on P bioavailability. To better understand this interaction, mechanistic models representing small-scale nutrient gradients and water dynamics in the rhizosphere of full-grown root systems are needed.MethodsRice was grown in large columns using a P-deficient soil at three different P supplies in the topsoil (deficient, suboptimal, non-limiting) in combination with two water regimes (field capacity versus drying periods). Root architectural parameters and P uptake were determined. Using a multiscale model of water and nutrient uptake, in-silico experiments were conducted by mimicking similar P and water treatments. First, 3D root systems were reconstructed by calibrating an architecure model with observed phenological root data, such as nodal root number, lateral types, interbranch distance, root diameters, and root biomass allocation along depth. Secondly, the multiscale model was informed with these 3D root architectures and the actual transpiration rates. Finally, water and P uptake were simulated.Key resultsThe plant P uptake increased over threefold by increasing P and water supply, and drying periods reduced P uptake at high but not at low P supply. Root architecture was significantly affected by the treatments. Without calibration, simulation results adequately predicted P uptake, including the different effects of drying periods on P uptake at different P levels. However, P uptake was underestimated under P deficiency, a process likely related to an underestimated affinity of P uptake transporters in the roots. Both types of laterals (i.e. S- and L-type) are shown to be highly important for both water and P uptake, and the relative contribution of each type depend on both soil P availability and water dynamics. Key drivers in P uptake are growing root tips and the distribution of laterals.ConclusionsThis model-data integration demonstrates how multiple co-occurring single root phene responses to environmental stressors contribute to the development of a more efficient root system. Further model improvements such as the use of Michaelis constants from buffered systems and the inclusion of mycorrhizal infections and exudates are proposed.

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