Control of root morphogenesis for improved mechanical stability in container-grown lodgepole pine

Lodgepole pine (Pinuscontorta Dougl.) seedlings were raised in containers (Styroblocks) painted with a root-growth inhibitor (exterior latex paint containing 0.1 kg/ℓ basic cupric carbonate). Contact with this wall coating completely inhibited the elongation of lateral roots, thereby preventing them from growing down or around the container wall. However, when the seedlings were planted, the inhibited lateral roots very quickly resumed growth. Consequently, the trees soon acquired a root system quite similar in basic form to that of a naturally established seedling.

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Longleaf Pine Root System Development and Seedling Quality in Response to Copper Root Pruning and Cavity Size

Southern Journal of Applied Forestry ◽

10.1093/sjaf/35.1.5 ◽

2011 ◽

Vol 35 (1) ◽

pp. 5-11 ◽

Cited By ~ 8

Author(s):

Mary Anne Sword Sayer ◽

Shi-Jean Susana Sung ◽

James D. Haywood

Keyword(s):

Root Growth ◽

Root System ◽

System Development ◽

Longleaf Pine ◽

Lateral Roots ◽

Dry Weight ◽

Root Pruning ◽

Cavity Size ◽

Root System Development ◽

Primary Lateral

Abstract Cultural practices that modify root system structure in the plug of container-grown seedlings have the potential to improve root system function after planting. Our objective was to assess how copper root pruning affects the quality and root system development of longleaf pine seedlings grown in three cavity sizes in a greenhouse. Copper root pruning increased seedling size, the allocation of root system dry weight to the taproot, and the fraction of fibrous root mass allocated to secondary lateral roots compared with primary lateral roots. It decreased the allocation of root system dry weight to primary lateral roots and led to a distribution of root growth potential that more closely resembled the root growth of naturally sown seedlings. These effects of copper root pruning may benefit longleaf pine establishment. However, because copper root pruning increased competition for cavity growing space among the taproot and fibrous roots, we suggest that recommendations regarding cavity size and seedling quality parameters be tailored for copper-coated cavities.

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Root growth of containerized lodgepole pine seedlings in response to Ascophyllum nodosum extract application during nursery culture

Canadian Journal of Plant Science ◽

10.4141/cjps2011-279 ◽

2012 ◽

Vol 92 (6) ◽

pp. 1207-1212 ◽

Cited By ~ 7

Author(s):

Joanne E. MacDonald ◽

Jen Hacking ◽

Yuhui Weng ◽

Jeff Norrie

Keyword(s):

Root Growth ◽

Root System ◽

Pinus Contorta ◽

Marine Alga ◽

Lodgepole Pine ◽

Ascophyllum Nodosum ◽

Control Applications ◽

Nursery Culture ◽

Pine Seedlings ◽

Spring Planting

MacDonald, J. E., Hacking, J., Weng, Y. and Norrie, J. 2012. Root growth of containerized lodgepole pine seedlings in response to Ascophyllum nodosum extract application during nursery culture. Can. J. Plant Sci. 92: 1207–1212. Vigorous root growth immediately after spring planting is crucial to ensure a well-developed root system before the occurrence of drought events associated with climate change. The objective of this study was to enhance spring root growth of containerized lodgepole pine (Pinus contorta Dougl. var. latifolia Engelm.) seedlings. Seedling culture began in April. In September, seedlings were root drenched with an extract of the brown marine alga Ascophyllum nodosum (L.) Le Jolis in finisher fertilizer at rates of 1:750, 1:500, and 1:250. Finisher fertilizer alone served as control. Applications were made three or six times. Seedling culture continued until lifting in December, and then seedlings were freezer stored. Frequency of application had no effect on root growth, whereas rate of application had a significant effect. Compared with control, the 1:750, 1:500, and 1:250 rates significantly reduced total length of the root system in mid October. After overwintering and growing under favorable environmental conditions for 21 d, the 1:500 rate significantly increased the total number of white roots, as well as the number of both short and long white roots. These results suggest that application of Ascophyllum nodosum extract may be a valuable nursery practice to increase spring root growth, thereby enhancing drought resistance.

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Disruption of CYCLOPHILIN 38 function reveals a photosynthesis-dependent systemic signal controlling lateral root emergence

10.1101/2020.03.11.985820 ◽

2020 ◽

Author(s):

Lina Duan ◽

Juan Manuel Pérez-Ruiz ◽

Francisco Javier Cejudo ◽

José R. Dinneny

Keyword(s):

Root Growth ◽

Root System ◽

Lateral Root ◽

System Development ◽

Lateral Roots ◽

Primary Root ◽

Root System Architecture ◽

Minor Effect ◽

Low Light ◽

Primary Root Growth

AbstractPhotosynthesis in leaves generates the fixed-carbon resources and essential metabolites that support sink tissues, such as roots [1]. One of these products, sucrose, is known to promote primary root growth, but it is not clear what other molecules may be involved and whether other stages of root system development are affected by photosynthate levels [2]. Through a mutant screen to identify pathways regulating root system architecture, we identified a mutation in the CYCLOPHILIN 38 (CYP38) gene, which causes an accumulation of pre-emergent stage lateral roots, with a minor effect on primary root growth. CYP38 was previously reported to maintain the stability of Photosystem II (PSII) in chloroplasts [3]. CYP38 expression is enriched in the shoot and grafting experiments show that the gene acts non-cell autonomously to promote lateral root emergence. Growth of wild-type plants under low light conditions phenocopied the cyp38 lateral root emergence phenotype as did the inhibition of PSII-dependent electron transport or NADPH production. Importantly, the cyp38 root phenotype is not rescued by exogenous sucrose, suggesting the involvement of another metabolite. Auxin (IAA) is an essential hormone promoting root growth and its biosynthesis from tryptophan is dependent on reductant generated during photosynthesis [4,5]. Both WT seedlings grown under low light and cyp38 mutants have highly diminished levels of IAA in root tissues. The cyp38 lateral root defect is rescued by IAA treatment, revealing that photosynthesis promotes lateral root emergence partly through IAA biosynthesis. Metabolomic profiling shows that the accumulation of several defense-related metabolites are also photosynthesis-dependent, suggesting that the regulation of a number of energy-intensive pathways are down-regulated when light becomes limiting.

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1002 ADAPTATION OF BEAN SEEDLINGS TO LOW P AVAILABILITY

HortScience ◽

10.21273/hortsci.29.5.573b ◽

1994 ◽

Vol 29 (5) ◽

pp. 573b-573

Author(s):

Jonathan Lynch

Keyword(s):

Root Growth ◽

Root System ◽

Geometric Model ◽

Lateral Roots ◽

System Size ◽

P Availability ◽

Growth Responses ◽

P Efficiency ◽

Physiological Basis ◽

Soil P

Low P availability is a primary limitation to plant growth on most native soils. Crop genotypes differ substantially in their ability to grow in low P soils. Understanding the physiological basis for such variation would be useful in developing genotypes with superior P efficiency, which would have utility in low-input systems and might permit more. efficient fertilizer use in high-input systems. In common bean (Phasecolus vulgaris), growth under P stress is reduced because of increased C costs of the root system. Genetic contrasts in P efficiency were not associated with reduced shoot requirement, mycorrhizal associations, chemical interactions with specific soil P pools, or root system size, but were associated with root system architecture. SimRoot, an explicit geometric model of bean root growth, confirmed that architectural traits can influence the relationship of root C costs and P acquisition. Root growth responds dynamically to P stress, through changes in the proliferation of lateral roots and the geotropic response of basal roots. Differences in root architecture arising from these growth responses to P stress may account for genetic differences in P efficiency.

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Toppling in British Columbia's Lodgepole Pine Plantations: Significance, Cause and Prevention

The Forestry Chronicle ◽

10.5558/tfc62433-5 ◽

1986 ◽

Vol 62 (5) ◽

pp. 433-439 ◽

Cited By ~ 21

Author(s):

A. N. Burdett ◽

P. A. F. Martin ◽

H. Coates ◽

R. Eremko

Keyword(s):

British Columbia ◽

Chemical Method ◽

Lodgepole Pine ◽

Lateral Roots ◽

Wood Formation ◽

Pine Plantations ◽

Reaction Wood ◽

Pine Seedlings ◽

Root Morphogenesis ◽

Primary Lateral

Young trees sometimes lean, or topple by pivoting about a point below the ground. Geotropic curvature in the lower part of the stem restores the leading shoot to the vertical. The resultant stem bowing reduces potential lumber recovery, and is associated with reaction wood formation. Toppling has occurred in lodgepole pine (Pinus conforta Dougl.) plantations throughout British Columbia. Generally the number of trees affected has been small; although in the southern interior of the province the majority of trees in some plantations have toppled. In areas where toppling in planted trees has occurred, naturally established lodgepole pine is relatively stable. Since planted trees are usually of the native provenance, this suggests that toppling in plantations is primarily the result of nursery and planting effects on root morphology. More normal root morphogenesis, and hence greater stability can be achieved by planting young seedlings that retain the capacity to initiate primary lateral roots. Pruning the lateral roots of older stock provides another approach. A chemical method for pruning lateral roots of container-grown lodgepole pine seedlings has been developed and adopted commercially in British Columbia and elsewhere.

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Capturing in-field root system dynamics with the RootTracker

10.1101/2020.11.14.382002 ◽

2020 ◽

Author(s):

Jeffrey J. Aguilar ◽

Matt Moore ◽

Logan Johnson ◽

Rachel F. Greenhut ◽

Eric Rogers ◽

...

Keyword(s):

Root Growth ◽

System Dynamics ◽

Root System ◽

System Architecture ◽

Mechanical Stability ◽

Genotypic Variation ◽

Root Systems ◽

Root System Architecture ◽

Rapid Responses ◽

The Face

AbstractOptimizing root system architecture offers a promising approach to developing stress tolerant cultivars in the face of climate change, as root systems are critical for water and nutrient uptake as well as mechanical stability. However, breeding for optimal root system architecture has been hindered by the difficulty in measuring root growth in the field. Here, we describe a technology, the RootTracker (RT), which employs capacitance touch sensors to monitor in-field root growth over time. Configured in a cylindrical shutter-like fashion around a planted seed, 264 electrodes are individually charged multiple times over the course of an experiment. Signature changes in the measured capacitance and resistance readings indicate when a root has touched or grown close to an electrode. Using the RootTracker, we have measured root system dynamics of commercial maize hybrids growing in both typical Midwest field conditions and under different irrigation regimes. We observed rapid responses of root growth to water deficits and found evidence for a “priming response” in which an early water deficit causes more and deeper roots to grow at later time periods. There was genotypic variation among hybrid maize lines in their root growth in response to drought, indicating a potential to breed for root systems adapted for different environments.

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Understanding Root Systems to Improve Seedling Quality

HortTechnology ◽

10.21273/horttech.8.4.544 ◽

1998 ◽

Vol 8 (4) ◽

pp. 544-549 ◽

Cited By ~ 10

Author(s):

Silvana Nicola

Keyword(s):

Root Growth ◽

Root System ◽

Seedling Growth ◽

Root Morphology ◽

Root Architecture ◽

Lateral Roots ◽

Root Systems ◽

The Third ◽

Observation Methods ◽

Different Types

Root architecture can be very important in plant productivity. The importance of studies on root morphology and development is discussed to improve seedling growth. Root systems of dicotyledonous species are reviewed, with emphasis on differences between growth of basal and lateral roots. The presence of different types of roots in plant species suggests possible differences in function as well. The architecture of a root system related to its functions is considered. Classical methods for studying root systems comprise excavation of root system, direct observation, and indirect analyses. While the first method is destructive and the third is effective in understanding root architecture only on a relatively gross scale, observation methods allow the scientist a complete a nondestructive architectural study of a root system. The three groups are reviewed related to their potential to give valuable information related to the root architecture and development of the seedling, with emphasis on the availability of a medium-transparent plant-growing system, enabling nondestructive daily observations and plant measurements under controlled environmental conditions. Effects of CO2 enrichment on seedling growth is reviewed, emphasizing the effects of CO2 on root growth.

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Utilization of a hydrate cellulose film for investigation of Arabidopsis thaliana L. root system growth and development

Biotekhnologiya ◽

10.21519/0234-2758-2020-36-1-36-43 ◽

2020 ◽

Vol 36 (1) ◽

pp. 36-43

Author(s):

I.O. Konovalova ◽

T.N. Kudelina ◽

S.O. Smolyanina ◽

A.I. Lilienberg ◽

T.N. Bibikova

Keyword(s):

Arabidopsis Thaliana ◽

Root System ◽

Life Support ◽

Higher Plants ◽

Plant Root ◽

Lateral Roots ◽

Basic Research ◽

Cellulose Film ◽

A New Technique ◽

Basic Research Project

A new technique for Arabidopsis thaliana cultivation has been proposed that combines the use of a phytogel-based nutrient medium and a hydrophilic membrane of hydrate cellulose film, separating the root system of the plant from the medium thickness. Growth rates of both main and lateral roots were faster in the plants cultivated on the surface of hydrate cellulose film than in the plants grown in the phytogel volume. The location of the root system on the surface of the transparent hydrate film simplifies its observation and analysis and facilitates plant transplantation with preservation of the root system configuration. The proposed technique allowed us to first assess the effect of exogenous auxin on the growth of lateral roots at the 5-6 developmental stage. methods to study plant root systems, hydrate cellulose film, A. thaliana, lateral roots, differential root growth rate, auxin The work was financially supported by the Russian Foundation for Basic Research (Project Bel_mol_a 19-54-04015) and the basic topic of the Russian Academy of Sciences - IBMP RAS «Regularities of the Influence of Extreme Environmental Factors on the Processes of Cultivation of Higher Plants and the Development of Japanese Quail Tissues at Different Stages of its Ontogenesis under the Conditions of Regenerative Life Support Systems».

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Lateral root formation and nutrients: nitrogen in the spotlight

Plant Physiology ◽

10.1093/plphys/kiab145 ◽

2021 ◽

Author(s):

Pierre-Mathieu Pélissier ◽

Hans Motte ◽

Tom Beeckman

Keyword(s):

Signaling Pathways ◽

Root System ◽

Root Development ◽

Lateral Root ◽

Molecular Mechanisms ◽

Root Formation ◽

Lateral Roots ◽

Nutrient Use Efficiency ◽

Lateral Root Formation ◽

Lateral Root Development

Abstract Lateral roots are important to forage for nutrients due to their ability to increase the uptake area of a root system. Hence, it comes as no surprise that lateral root formation is affected by nutrients or nutrient starvation, and as such contributes to the root system plasticity. Understanding the molecular mechanisms regulating root adaptation dynamics towards nutrient availability is useful to optimize plant nutrient use efficiency. There is at present a profound, though still evolving, knowledge on lateral root pathways. Here, we aimed to review the intersection with nutrient signaling pathways to give an update on the regulation of lateral root development by nutrients, with a particular focus on nitrogen. Remarkably, it is for most nutrients not clear how lateral root formation is controlled. Only for nitrogen, one of the most dominant nutrients in the control of lateral root formation, the crosstalk with multiple key signals determining lateral root development is clearly shown. In this update, we first present a general overview of the current knowledge of how nutrients affect lateral root formation, followed by a deeper discussion on how nitrogen signaling pathways act on different lateral root-mediating mechanisms for which multiple recent studies yield insights.

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