Resource availability modulates above- and below-ground competitive interactions between genotypes of a dominant C4grass

Abstract Competitive interactions between plants can affect patterns of allocation to reproductive structures through modulation of resource availability. As floral traits involved in plant attractiveness to pollinators can be sensitive to these resources, competition with any neighbouring species may influence the attractiveness of insect-pollinated plants. While pollination research has primarily focused on above-ground interactions, this study aims at investigating if the presence of a competitor plant can modulate neighbouring insect-pollinated plant attractiveness to pollinators and resulting fecundity, especially through below-ground competitive interactions for soil resources. We set up a plot experiment in which we grew an insect-pollinated plant, Sinapis alba (Brassicaceae), in a mixture dominated by a wind-pollinated plant, Holcus lanatus (Poaceae). Individuals of S. alba were either subjected to or isolated from (with buried tubes in the soil) below-ground competition. Across the flowering season, floral traits involved in attractiveness of S. alba and pollinator visitation were followed at the plot and plant level to investigate different scales of attractiveness. At the end of the experiment, seeds were harvested to assess plant fecundity. Competition had a significant negative effect on plot and plant floral display size as well as flower size while nectar traits were not affected. When plants of S. alba were in competition, the time to first visit was altered: the proportion of plots that received a visit was smaller for a given time; in other words, it took more time for a given proportion of plots to be visited and some plots were even never visited. Moreover, pollinators made fewer visits per plots. The proportion of viable seeds produced by S. alba in competition was lower and probably linked to the competition itself rather than changes in pollinator visitation. This study suggests that competitive interactions between plants can modulate pollination interactions even when competing plant species are not insect-pollinated.

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Kin recognition in an annual plant

Biology Letters ◽

10.1098/rsbl.2007.0232 ◽

2007 ◽

Vol 3 (4) ◽

pp. 435-438 ◽

Cited By ~ 269

Author(s):

Susan A Dudley ◽

Amanda L File

Keyword(s):

Kin Selection ◽

Competitive Ability ◽

Direct Evidence ◽

Kin Recognition ◽

Social Systems ◽

Competitive Interactions ◽

Annual Plant ◽

Root Interactions ◽

Cakile Edentula ◽

Below Ground

Kin recognition is important in animal social systems. However, though plants often compete with kin, there has been as yet no direct evidence that plants recognize kin in competitive interactions. Here we show in the annual plant Cakile edentula , allocation to roots increased when groups of strangers shared a common pot, but not when groups of siblings shared a pot. Our results demonstrate that plants can discriminate kin in competitive interactions and indicate that the root interactions may provide the cue for kin recognition. Because greater root allocation is argued to increase below-ground competitive ability, the results are consistent with kin selection.

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A simple model for the influence of habitat resource availability on lateral clonal spread

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2015.0327 ◽

2015 ◽

Vol 282 (1806) ◽

pp. 20150327 ◽

Cited By ~ 3

Author(s):

Martin Weiser ◽

Jan Smyčka

Keyword(s):

Simple Model ◽

Resource Availability ◽

Clonal Growth ◽

Null Model ◽

Availability Analysis ◽

Optimal Distance ◽

High Prevalence ◽

Below Ground ◽

Clonal Spread ◽

Plant Community Assembly

Plant clonal spread is ubiquitous and of great interest, owing both to its key role in plant community assembly and its suitability for plant behaviour research. However, mechanisms that govern spreading distance are not well known. Here we link spacer costs and below-ground competition in a simple model of growth in a homogeneous below-ground environment, in which optimal distance between ramets is based on minimizing the sum of these costs. Using this model, we predict a high prevalence of clonal growth that does not employ spacers in resource-poor environments and a nonlinear increase in spreading distance in response to increasing below-ground resource availability. Analysis of database data on clonal growth in relationship to below-ground resource availability revealed that patterns of the spread based on stolons is compatible with the model's predictions. As expected, model prediction failed for rhizomatous species, where spacer sizes are likely to be selected mainly to play roles other than spread. The model's simplicity makes it useful as a null model in testing hypotheses about the effects of environmental heterogeneity on clonal spread.

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Phenology of competitive interactions and implications for management of the invasive wetland plant Alternanthera philoxeroides

10.21079/11681/42188 ◽

2021 ◽

Author(s):

Nathan Harms ◽

James Cronin

Keyword(s):

Resource Availability ◽

Technical Note ◽

Priority Effects ◽

Competitive Interactions ◽

Alternanthera Philoxeroides ◽

Field Observations ◽

Wetland Plant ◽

Resident Species ◽

Early Season ◽

Emergent Species

Phenological differences between invading plants and members of recipient communities may increase the success of invaders because of priority effects. Thus, the application of management when the invader has a phenological advantage (for example, early in the year) can benefit other species by increasing resource availability. This technical note summarizes results from a combination of field observations and a mesocosm experiment to explore whether phenological differences between the invasive wetland plant, alligatorweed (Alternanthera philoxeroides [Mart.] Grseb.), and resident species contribute to alligatorweed success. We documented over two years the early-season growth of alligatorweed and other species at 12 sites in Louisiana, USA. We then conducted a subsequent mesocosm competition experiment between alligatorweed and a common wetland emergent species, spotted lady’s thumb (Persicaria maculosa [L.] Small), over a full year to detect differences in timing of growth and competitive interactions under two fertilizer levels.

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Competitive interactions betweenNardus strictaL. andCalluna vulgaris(L.) Hull: the effect of fertilizer and defoliation on above- and below-ground performance

Journal of Ecology ◽

10.1046/j.1365-2745.1999.00353.x ◽

1999 ◽

Vol 87 (2) ◽

pp. 330-340 ◽

Cited By ~ 58

Author(s):

S. E. Hartley ◽

L. Amos

Keyword(s):

Competitive Interactions ◽

Below Ground

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Measuring Impact of Stress in Sandwich Generation Caring for Demented Parents

GeroPsych ◽

10.1024/1662-9647/a000114 ◽

2014 ◽

Vol 27 (4) ◽

pp. 171-179 ◽

Cited By ~ 6

Author(s):

Laurence M. Solberg ◽

Lauren B. Solberg ◽

Emily N. Peterson

Keyword(s):

Factor Analysis ◽

Exploratory Factor Analysis ◽

Social Worker ◽

Resource Availability ◽

Well Being ◽

Sandwich Generation ◽

Item Questionnaire ◽

Significant Difference ◽

Adult Caregivers ◽

The Impact

Stress in caregivers may affect the healthcare recipients receive. We examined the impact of stress experienced by 45 adult caregivers of their elderly demented parents. The participants completed a 32-item questionnaire about the impact of experienced stress. The questionnaire also asked about interventions that might help to reduce the impact of stress. After exploratory factor analysis, we reduced the 32-item questionnaire to 13 items. Results indicated that caregivers experienced stress, anxiety, and sadness. Also, emotional, but not financial or professional, well-being was significantly impacted. There was no significant difference between the impact of caregiver stress on members from the sandwich generation and those from the nonsandwich generation. Meeting with a social worker for resource availability was identified most frequently as a potentially helpful intervention for coping with the impact of stress.

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