Perception of neighbouring plants by rhizomes and roots: morphological manifestations of a clonal plant

A previous study showed that clonal morphology of the rhizomatous grass Elymus lanceolatus ssp. lanceolatus (Scibner & J.G. Smith Gould) was influenced more by neighbouring root systems than by the local distribution of nutrients. In this study we determine whether individual rhizomes or roots of E. lanceolatus perceive neighbouring root systems and how this is manifested in morphological responses of E. lanceolatus clones. Elymus lanceolatus was grown in the same bin with Pseudoroegneria spicata (Pursh) A. Love or Agropyron desertorum (Fisch. ex Link) Schult. plants. Elymus lanceolatus was separated from its neighbours by different barriers. The barriers allowed either only E. lanceolatus roots; only a single E. lanceolatus primary rhizome; or both roots and rhizomes to contact the neighbour root system. When only a single E. lanceolatus primary rhizome with potentially developing branching rhizomes made contact with the neighbour, the clonal structure of E. lanceolatus was modified more with P. spicata as the neighbour than with A. desertorum. With root contact of E. lanceolatus alone there was a similar effect with the neighbouring plants, but there was a more marked inhibitory effect on E. lanceolatus clonal growth with P. spicata than with A. desertorum, compared with the treatment with only a single rhizome in contact with the neighbour. Root resource competition in the unconstrained treatment (roots and rhizomes) between neighbouring plant and E. lanceolatus was more apparent with A. desertorum than with P. spicata. This study is one of the first to document that rhizome and root contact of a clonal plant with its neighbours may induce different clonal responses depending on the species of neighbour. Key words: Agropyron desertorum, clonal morphology, Elymus lanceolatus ssp. lanceolatus, plant interference, plant contact, Pseudoroegneria spicata, rhizome structure, root systems.

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Registration of Pseudoroegneria Spicata ✕ Elymus Lanceolatus Hybrid Germplasm SL‐ 1

Crop Science ◽

10.2135/cropsci1991.0011183x003100050082x ◽

1991 ◽

Vol 31 (5) ◽

pp. 1391-1391 ◽

Cited By ~ 6

Author(s):

K. H. Asay ◽

D. R. Dewey ◽

K. B. Jensen ◽

W. H. Horton ◽

K. W. Maughan ◽

...

Keyword(s):

Pseudoroegneria Spicata ◽

Elymus Lanceolatus

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Cytogenetics of Elymus caucasicus and Elymus longearistatus (Poaceae: Triticeae)

Genome ◽

10.1139/g91-133 ◽

1991 ◽

Vol 34 (6) ◽

pp. 860-867 ◽

Cited By ~ 16

Author(s):

Kevin B. Jensen ◽

Richard R.-C. Wang

Keyword(s):

Chromosome Pairing ◽

Interspecific Hybrid ◽

Intergeneric Hybrids ◽

Cytological Analysis ◽

Meiotic Behavior ◽

Pseudoroegneria Spicata ◽

Central Asian ◽

Elymus Lanceolatus

Two accessions of Elymus caucasicus (Koch) Tzvelev and three accessions of Elymus longearistatus (Boiss.) Tzvelev were studied to determine the meiotic behavior and chromosome pairing in the two taxa, their interspecific hybrid, and their hybrids with various "analyzer" parents. Interspecific and intergeneric hybrids of the target taxa were obtained with the following analyzer species: Pseudoroegneria spicata (Pursh) A. Löve (2n = 14, SS), Pseudoroegneria libanotica (Hackel) D. R. Dewey (2n = 14, SS), Hordeum violaceum Boiss. &Hohenacker (2n = 14, HH) (= Critesion violaceum (Boiss. &Hohenacker) A. Löve), Elymus lanceolatus (Scribn. &Smith) Gould (2n = 28, SSHH), Elymus abolinii (Drob.) Tzvelev (2n = 28, SSYY), Elymus pendulinus (Nevski) Tzvelev (2n = 28, SSYY), Elymus fedtschenkoi Tzvelev (2n = 28, SSYY), Elymus panormitanus (Parl.) Tzvelev (2n = 28, SSYY), and Elymus drobovii (Nevski) Tzvelev (2n = 42, SSHHYY). Cytological analysis of their F1 hybrids showed that E. caucasicus and E. longearistatus were allotetraploids comprising the same basic genomes. Chromosome pairing in the E. caucasicus × P. libanotica hybrid demonstrated that the target taxa contained the S genome, based on 6.1 bivalents per cell. The lack of chromosome pairing, less than one bivalent per cell, in the E. longearistatus × H. violaceum hybrid showed that the H genome was absent. Increased pairing in the tetraploid and pentaploid hybrids when the Y genome was introduced indicated that the second genome in the two taxa was a segmental homolog of the Y genome. The S and Y genomes in E. caucasicus and E. longearistatus have diverged from each other and from those in many of the eastern and central Asian SY tetraploids.Key words: genome, meiosis, chromosome pairing, morphology, hybrid, Triticeae.

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An investigation into the possible inhibitory effects of white cypress pine (Callitris glaucophylla) litter on the germination and growth of associated ground cover species

Australian Journal of Botany ◽

10.1071/bt02045 ◽

2003 ◽

Vol 51 (1) ◽

pp. 93 ◽

Cited By ~ 26

Author(s):

Mark R. Harris ◽

David Lamb ◽

Peter D. Erskine

Keyword(s):

Resource Competition ◽

Seedling Emergence ◽

Ground Cover ◽

Inhibitory Effect ◽

Water Holding Capacity ◽

Pine Seedlings ◽

Callitris Glaucophylla ◽

Germination And Growth ◽

Water Holding ◽

Cypress Pine

White cypress-pine stands typically support sparse densities of shrubs and grasses. The commonly held opinion is that leaching of allelopathic chemical compounds from cypress-pine litter partly facilitates this exclusion. Germination and growth of cypress pine seedlings do not appear to be similarly affected. This study set out to determine whether cypress litter had a differential effect on germination and growth of cypress-pine seedlings and on associated ground-cover species. Glasshouse trials comparing seedling emergence under cypress- and artificial-litter layers were undertaken. Cypress-pine litter did not have an inhibitory effect on the germination or growth of ground-cover species. In most cases, seedling emergence was facilitated by the application of cypress-pine litter due to its ability to increase the water holding capacity of the underlying soil. Cypress litter did not promote growth of its own seedlings over its competitors except on coarse-textured soils where it provided an ameliorative function to water stress due to the soil's reduced water holding capacity. The inhibition of ground-cover species' germination and growth in pure cypress stands was suggested to be the result of high below-ground resource competition due to the pine's expansive root morphology.

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Resource Allocation Patterns as a Function of Clonal Morphology: A General Model Applied to a Foraging Clonal Plant

Journal of Ecology ◽

10.2307/2260730 ◽

1991 ◽

Vol 79 (2) ◽

pp. 519 ◽

Cited By ~ 34

Author(s):

Hans de Kroon ◽

Feike Schieving

Keyword(s):

Resource Allocation ◽

General Model ◽

Clonal Plant ◽

Allocation Patterns ◽

Clonal Morphology

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Opportunities for geitonogamy in the clonal herb Maianthemum dilatatum

Canadian Journal of Botany ◽

10.1139/b05-096 ◽

2005 ◽

Vol 83 (9) ◽

pp. 1082-1087 ◽

Cited By ~ 6

Author(s):

Amy S.G. Wilson ◽

Bart J. van der Kamp ◽

Carol Ritland

Keyword(s):

Plant Species ◽

Seed Set ◽

Natural Populations ◽

Clonal Plant ◽

Spatial Proximity ◽

Clonal Structure ◽

Female Reproductive Success ◽

Pollinator Behaviour ◽

Diverse Range ◽

Clonal Morphology

Clonal plant species have a diverse range of morphologies, which influences the spatial proximity of clonemates, which may affect the rate of geitonogamy. This study measured fine-scale clonal structure, pollinator behaviour, and impacts of geitonogamy on seed set in Maianthemum dilatatum (A. Wood) Nels. & J.F. Macbr., a herb with a spreading clonal morphology. Despite having a dispersive habit, on average more than 75% of the 10 nearest flowering neighbours of a ramet were clonemates of that ramet. Pollinators foraged preferentially among near-neighbours, but during bouts, visitors typically visited only two floral ramets, effectively lowering the expected contribution to geitonogamy based on flight distances alone. Experimental hand pollinations, pollinator exclusion, and emasculation treatments provided evidence that geitonogamy attributable to pollen from neighbouring ramets may reduce seed set in natural populations through a mechanism of self-interference. Even in a dispersive clonal plant species such as M. dilatatum, clonemate-level geitonogamy is a likely factor constraining female reproductive success.

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Growth and Nitrogen Uptake by Agropyron desertorum and Pseudoroegneria spicata when Exposed to Nitrate Pulses of Different Duration

Functional Plant Biology ◽

10.1071/pp97039 ◽

1997 ◽

Vol 24 (5) ◽

pp. 637 ◽

Cited By ~ 8

Author(s):

M. Cui ◽

M. M. Caldwell

Keyword(s):

Mixed Culture ◽

Pulse Duration ◽

Nitrate Uptake ◽

Plant Biomass ◽

Perennial Grasses ◽

Shoot Biomass ◽

Pseudoroegneria Spicata ◽

Agropyron Desertorum ◽

Shoot Ratio ◽

Root Shoot Ratio

Plant growth and nitrate uptake were measured for two Great Basin perennial grasses, Agropyron desertorum and Pseudoroegneria spicata, in sand-filled pots in either monoculture or mixed culture (2 plants/pot). All plants were supplied with the same initial amount of nitrate but delivered in five different pulse durations ranging from 0.5 to 72 h. The pulse duration was controlled by flushing the pots with water at different times after applying the nitrate pulse. The same concentration of nitrate was used in all pulse treatments. Increasing the pulse duration led to significantly increased plant biomass production for both species in both mono- and mixed cultures, and to reduced root/shoot biomass ratio. Biomass and root/shoot ratio were greater for Agropyron in mixed culture than in monoculture. To assess root nitrate uptake capacity, a 30-min tracer pulse was applied to all plants. Plants that had been exposed to longer pulses acquired significantly more nitrate than those that had been exposed to shorter pulses for both total plant acquisition and acquisition per unit root length. With greater root/shoot ratio than Pseudoroegneria, total nitrate acquisition by Agropyron was significantly greater at most pulse durations. Root nitrate uptake per unit mass was also greater for Agropyron than for Pseudoroegneria, indicating that Agropyron is more responsive to nitrate pulsing.

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Cytology, fertility, and morphology of Elymus kengii (Keng) Tzvelev and E. grandiglumis (Keng) A. Löve (Triticeae: Poaceae)

Genome ◽

10.1139/g90-083 ◽

1990 ◽

Vol 33 (4) ◽

pp. 563-570 ◽

Cited By ~ 47

Author(s):

Kevin B. Jensen

Keyword(s):

Chromosome Pairing ◽

Interspecific Hybrids ◽

Central China ◽

Psathyrostachys Huashanica ◽

Pseudoroegneria Spicata ◽

Polyploid Evolution ◽

Mode Of Reproduction ◽

Psathyrostachys Juncea ◽

Glume Length ◽

Elymus Lanceolatus

This study reports on the cytogenetics, fertility, mode of reproduction, and morphological variation of two perennial Triticeae grasses, Elymus kengii (Keng) Tzvelev and Elymus grandiglumis (Keng) A. Löve, from west central China. Both species are allohexaploids (2n = 42), self-fertile, and morphologically distinct on the basis of their plant color, glume length, and lemma and rachis vestiture. F1 hybrids between these two species are partially fertile and morphologically intermediate to their parents. Analysis of chromosome pairing in hybrids between E. grandiglumis or E. kengii and the following "analyzer" species, Psathyrostachys juncea (Fisch.) Nevski (NN), Psathyrostachys huashanica Keng (NN), Elymus lanceolatus (Scribn. &Smith) Gould (SSHH), Elymus dentatus (Hook. f.) Tzvelev ssp. ugamicus (Drob.) Tzvelev (SSYY), Elymus ciliaris (Trin.) Nevski (SSYY), Pseudoroegneria spicata (Pursh) A Löve (SS), and Pseudoroegneria tauri (Boiss. &Bal.) A. Löve (SSPP), suggested that both taxa contain the S, Y, and P genomes. This represents a new genome combination not previously reported and shows that the P genome from the crested wheatgrasses (Agropyron) has been involved in polyploid evolution within the. Triticeae.Key words: genome, meiosis, chromosome pairing, interspecific hybrids, Elymus, Triticeae.

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