Seedling emergence of Betula maximowicziana following human disturbance and the role of buried viable seeds

Sheep and hair fescue are perennial, tuft forming grasses that spread by seed and form dense sods in wild blueberry fields. These sods compete with the crop for resources and hinder harvest. Field and greenhouse studies were conducted in 2015 to evaluate 1) the effect of sequential glufosinate and foramsulfuron applications on suppression of fescues in the greenhouse and field, and 2) efficacy of glufosinate and foramsulfuron on fescue seedlings when applied at 2, 4, 6, and 8 wk after seedling emergence in the greenhouse. Glufosinate applications at 750 and 1,005 g ai ha−1followed by foramsulfuron application at 35 g ai ha−1reduced fescue leaf number and biomass relative to foramsulfuron application alone in the greenhouse. In the field study, fescue flowering tuft density, tuft inflorescence height, seed production, and seed viability were reduced by foramsulfuron alone, but there was a trend towards lower seed production and tuft height when fescues were treated with glufosinate at 1,005 g ha−1followed by foramsulfuron. Foramsulfuron caused low seedling mortality at all application timings evaluated, but glufosinate caused >90% mortality in seedlings when applied at 2, 4, 6, or 8 wk after seedling emergence. Our results suggest that sequential applications of these herbicides are less effective under field conditions relative to results obtained in the greenhouse, though burndown glufosinate applications may have a role in reducing fescue seedling recruitment. Additional research should be conducted to determine the effect of early spring and autumn glufosinate applications on fescue seedling recruitment and suppression of established fescue tufts with subsequent foramsulfuron applications.

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The Role of Population Origin and Microenvironment in Seedling Emergence and Early Survival in Mediterranean Maritime Pine (Pinus pinaster Aiton)

PLoS ONE ◽

10.1371/journal.pone.0109132 ◽

2014 ◽

Vol 9 (10) ◽

pp. e109132 ◽

Cited By ~ 18

Author(s):

Natalia Vizcaíno-Palomar ◽

Bárbara Revuelta-Eugercios ◽

Miguel A. Zavala ◽

Ricardo Alía ◽

Santiago C. González-Martínez

Keyword(s):

Pinus Pinaster ◽

Seedling Emergence ◽

Maritime Pine ◽

Population Origin ◽

Early Survival

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Stimulation of Common Cocklebur (Xanthium pensylvanicum) and Redroot Pigweed (Amaranthus retroflexus) Seed Germination by Injections of Ethylene into Soil

Weed Science ◽

10.1017/s0043174500061129 ◽

1980 ◽

Vol 28 (5) ◽

pp. 510-514 ◽

Cited By ~ 18

Author(s):

G. H. Egley

Keyword(s):

Seed Germination ◽

Laboratory Tests ◽

Seedling Emergence ◽

Amaranthus Retroflexus ◽

Redroot Pigweed ◽

Plastic Bags ◽

Viable Seeds ◽

Chamber Studies ◽

Growth Chamber Studies ◽

Stimulation Of

The effects of ethylene upon germination of common cocklebur (Xanthium pensylvanicumWallr.) and redroot pigweed (Amaranthus retroflexusL.) seeds were studied. In laboratory tests with seeds in sealed flasks in the dark, 10 μl/L ethylene increased germination of redroot pigweed seeds from 7% to 52% at 30 C, and increased germination of large and small common cocklebur seeds from 30% and 0% to 100% and 90% respectively, at 25 C. At least 12 h of exposure to ethylene was necessary for appreciable stimulation of germination. In growth chamber studies with known numbers of seeds in pots of soil, ethylene at 11 kg/ha was injected into the soil, and the pots were enclosed in plastic bags for 24 h. One such injection at 2 weeks after planting, and successive injections at 2, 3, and 4 weeks, significantly increased redroot pigweed seedling emergence, and significantly decreased the numbers of dormant, viable seeds remaining in the soil. When pots were not enclosed, injections did not significantly effect redroot pigweed seeds, but significantly increased common cocklebur seedling emergence and decreased the number of viable common cocklebur seeds remaining in the soil.

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Viable seed populations by soil depth and potential site recolonization after disturbance

Canadian Journal of Botany ◽

10.1139/b77-274 ◽

1977 ◽

Vol 55 (18) ◽

pp. 2408-2412 ◽

Cited By ~ 88

Author(s):

Janice M. Moore ◽

Ross W. Wein

Keyword(s):

Soil Depth ◽

Seedling Emergence ◽

Mineral Soil ◽

Organic Soil ◽

Viable Seed ◽

Soil Layers ◽

Forest Experiment Station ◽

Viable Seeds ◽

Study Sites ◽

Germination Experiment

Seedling emergence from organic and mineral soil layers was measured for nine study sites at the Acadia Forest Experiment Station near Fredericton, New Brunswick. The number of viable seeds showed a decrease from deciduous-dominated forest, to conifer-dominated forest, to organic soil study sites. Viable seed number varied from 3400/m2 for a deciduous-dominated forest study site to zero for a bog study site. Most seeds germinated from the upper organic soil layers of all study sites and were predominantly Rubus strigosus Michx. After the germination experiment, ungerminated seeds, which showed no viability by the tetrazolium test, were separated from the soil. These seeds were almost entirely Betula spp. and seed numbers were as high as 4200–9400/m2 for a deciduous-dominated forest. The applicability of the results to differing types of postdisturbance revegetation is discussed.

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Sheep gut passage and survival of Mediterranean shrub seeds

Seed Science Research ◽

10.1079/ssr2004192 ◽

2005 ◽

Vol 15 (1) ◽

pp. 21-28 ◽

Cited By ~ 45

Author(s):

Pablo Manzano ◽

Juan E. Malo ◽

Begoña Peco

Keyword(s):

Potential Role ◽

Central Spain ◽

Long Distance ◽

Retama Sphaerocarpa ◽

Gut Passage ◽

Lavandula Stoechas ◽

Significant Difference ◽

Ecological Importance ◽

Viable Seeds

Although viable seeds of Mediterranean dry-fruited shrubs are found in herbivore dung, the ecological importance of this observation is still not well understood. We analysed seed retrieval percentages, defecation time and germinability after sheep gut passage for the five most common shrub species of an area in central Spain (Retama sphaerocarpa, Cytisus scoparius, Halimium umbellatum subsp. viscosum, Cistus ladanifer and Lavandula stoechas subsp. pedunculata). Five ewes were fed seeds, and their dung was collected regularly during the following week. Seeds were hand-sorted from dung subsamples and tested for germinability. The defecated seeds were clustered in time, with a majority retrieved in the 24–40 h period, although over 1% of the seeds were retained in the gut for more than 72 h. Data suggested a possible link between seed size and retrieval, with medium-sized seeds less damaged (16–23%) than larger and smaller seeds (10–12%), although only a small number of species were studied. Germination results showed an increased percentage of germination after gut passage for H. umbellatum (x2 test, P<0.05) and a marginally significant difference for C. scoparius (P<0.1). Soft-seeded L. stoechas did not germinate after gut passage. The results indicate a potential role of herbivore endozoochory for the long-distance dispersal of dry-fruited shrubs and their potential colonization of distant sites.

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Seed and Seedling Biology of the Woody-fruited Proteaceae

Australian Journal of Botany ◽

10.1071/bt96135 ◽

1998 ◽

Vol 46 (4) ◽

pp. 387 ◽

Cited By ~ 35

Author(s):

Philip K. Groom ◽

Byron B. Lamont

Keyword(s):

Drought Stress ◽

Seedling Establishment ◽

Comparative Biology ◽

Wet Season ◽

Successful Establishment ◽

Drought Resistant ◽

Viable Seeds ◽

In Fire ◽

Great Scope

Within the Proteaceae, 353 species confined to 7 genera in the Grevilleoideae have woody fruits. The majority (> 70%) occur in fire-prone vegetation on nutrient-poor, summer-dry soils of south-western Australia. These species are characterised by large, winged seeds contained within serotinous follicles. Seed release is mediated by desiccation of the follicle walls resulting from fruit death, although wet–dry cycles are required in some genera. After release, germination must take place by the next wet season, as the seeds are not long-lived. Seeds are particularly high in protein (40–60%), P (1–2%) and Fe (10–60‰) compared with other Proteaceae. Seeds are favoured food for pre- and post-dispersal granivores (insects, birds, rodents) and young seedlings are favoured by herbivores (insects, marsupials), with the more serotinous fruits providing extra protection for their seeds. Successful establishment is facilitated by the protective and water retentive role of the testa during germination, and the remobilisation of N and P from the cotyledons to the seedling within 10 weeks of emergence. Drought stress reduces seedling establishment in otherwise favourable postfire microsites and prevents it (assisted by herbivores) in mature vegetation. Typically, < 10% of seeds released after fire become seedlings, and < 50% of these survive the first summer. Among fire-killed species, species that produce few seeds are more likely to have drought-resistant seedlings, often associated with larger seeds and/or needle-shaped leaves. Species that resprout after fire produce a few large viable seeds per plant, whereas fire-killed species produce many smaller seeds. Of all the Proteaceae, the ecology of woody-fruited species is best known, providing great scope for comparative biology studies.

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Auxin: Hormonal Signal Required for Seed Development and Dormancy

Plants ◽

10.3390/plants9060705 ◽

2020 ◽

Vol 9 (6) ◽

pp. 705 ◽

Cited By ~ 2

Author(s):

Angel J. Matilla

Keyword(s):

Seed Development ◽

Higher Plants ◽

Aba Signaling ◽

Seed Formation ◽

Cellular Processes ◽

Primary Dormancy ◽

Cellular Machinery ◽

Hormonal Signal ◽

Viable Seeds

The production of viable seeds is a key event in the life cycle of higher plants. Historically, abscisic acid (ABA) and gibberellin (GAs) were considered the main hormones that regulate seed formation. However, auxin has recently emerged as an essential player that modulates, in conjunction with ABA, different cellular processes involved in seed development as well as the induction, regulation and maintenance of primary dormancy (PD). This review examines and discusses the key role of auxin as a signaling molecule that coordinates seed life. The cellular machinery involved in the synthesis and transport of auxin, as well as their cellular and tissue compartmentalization, is crucial for the development of the endosperm and seed-coat. Thus, auxin is an essential compound involved in integuments development, and its transport from endosperm is regulated by AGAMOUS-LIKE62 (AGL62) whose transcript is specifically expressed in the endosperm. In addition, recent biochemical and genetic evidence supports the involvement of auxins in PD. In this process, the participation of the transcriptional regulator ABA INSENSITIVE3 (ABI3) is critical, revealing a cross-talk between auxin and ABA signaling. Future experimental aimed at advancing knowledge of the role of auxins in seed development and PD are also discussed.

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Increased weed emergence and seed bank depletion by soil disturbance in a no-tillage system

Weed Science ◽

10.1017/s0043174500092778 ◽

1997 ◽

Vol 45 (2) ◽

pp. 234-241 ◽

Cited By ~ 40

Author(s):

Dawit Mulugeta ◽

David E. Stoltenberg

Keyword(s):

Seed Bank ◽

Seedling Emergence ◽

Soil Disturbance ◽

No Tillage ◽

Common Lambsquarters ◽

Redroot Pigweed ◽

Giant Foxtail ◽

Tillage System ◽

Level Of Aggregation ◽

Viable Seeds

The influence of secondary soil disturbance on the emergence pattern and seed bank depletion of an annual weed community in a long-term, no-tillage corn cropping system was determined in 1992 and 1993. As a component of this research, the seed bank was characterized prior to implementation of soil disturbance treatments. The seed bank was initially composed of common lambsquarters, redroot pigweed, and giant foxtail, with approximately 55, 36, and 8% of the total viable seeds, respectively. The remaining 1% was comprised of five other species in 1992 and eight in 1993. The spatial distribution of viable seeds of each species, except common lambsquarters and redroot pigweed, was described by a negative binomial distribution. Three dispersion indices indicated that seeds of individual and total weed species were aggregated and that the level of aggregation of viable seeds of a species was associated with seed density; at lower seed densities, the level of aggregation was greater. Soil disturbance increased common lambsquarters emergence 6-fold in 1992 relative to nondisturbed soil, but did not influence emergence in 1993. Rainfall was about 50% less in 1993. In contrast, soil disturbance increased giant foxtail and redroot pigweed emergence approximately 6- and 3-fold in 1992 and 1993, respectively. Seedling emergence associated with soil disturbance, relative to nondisturbed soil, increased seed bank depletion of common lambsquarters 16-fold in 1992, and giant foxtail and redroot pigweed and average of 6- and 3-fold in 1992 and 1993, respectively. These results indicated that soil disturbance increased seedling emergence and seed bank depletion of the predominant species in the weed community of a long-term, no-tillage system, but that this response was dependent on rainfall for common lambsquarters.

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Eurasian Beaver (Castor fiber) Winter Foraging Preferences in Northern Poland—The Role of Woody Vegetation Composition and Anthropopression Level

Animals ◽

10.3390/ani10081376 ◽

2020 ◽

Vol 10 (8) ◽

pp. 1376

Author(s):

Mateusz Jackowiak ◽

Peter Busher ◽

Dagny Krauze-Gryz

Keyword(s):

Linear Model ◽

Plant Species ◽

Human Disturbance ◽

Generalized Linear Model ◽

Woody Plants ◽

Woody Species ◽

Eurasian Beaver ◽

Northern Poland ◽

Foraging Preferences

We studied beavers’ dietary preferences and the role of several factors (such as plant species, size and anthropopression level) that affect the beavers’ foraging in northern Poland. Woody plants along the river were measured and classified according to species in six 100 m-long transects that were characterized by a diversified human disturbance level. Ivlev’s electivity index was used to present the beavers’ preferences for various plant species and sizes, and the generalized linear model was used to assess the significance of studied factors in beavers’ browsing choices. Most popular in the beavers’ diets were willows (Salix), maples (Acer) and alder (Alnus), but only willows and maples were preferred. We noted a decrease in the beavers’ foraging preference in parallel to an increase in the shoot diameter; plants with a diameter below 10 cm were preferred. All factors included in the generalized linear model (GLM) were significant in shaping the beavers’ foraging choices. A negative correlation between the shoot diameter and the human disturbance level was found, but the species composition of the browsed woody plants was the same in each transect. Beavers’ foraging preferences, as observed in our study, were similar to those described in the literature and confirmed the role of woody species and their diameters in shaping the beavers’ diet. We also suggested the potential role of anthropopression in the shaping of the beavers’ foraging behaviors.

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The role of cotyledons in growth and development of woody angiosperms

Canadian Journal of Botany ◽

10.1139/b74-028 ◽

1974 ◽

Vol 52 (1) ◽

pp. 239-245 ◽

Cited By ~ 14

Author(s):

P. E. Marshall ◽

T. T. Kozlowski

Keyword(s):

Light Intensity ◽

Seedling Emergence ◽

Robinia Pseudoacacia ◽

Dry Weight ◽

Weight Increase ◽

Betula Alleghaniensis ◽

Ulmus Americana ◽

Weight Increment ◽

Stems And Leaves

The role of photosynthetically active cotyledons in the growth of young woody angiosperm seedlings was studied over a 35-day period under controlled environmental conditions. Two experiments were performed. In the first, cotyledons of Robinia pseudoacacia, Ulmus americana, and Ailanthus altissima were removed or covered at 7, 14, or 21 days after seedling emergence. In the second experiment, seedlings of Robinia pseudoacacia, Betula alleghaniensis, and Acer saccharum were grown over a range of light intensities. Removing or covering Robinia cotyledons of seedlings of any age resulted in lower dry weights of roots and stems than in controls. Removing or covering cotyledons of only 7-day-old Robinia seedlings retarded dry weight increase of foliage. Robinia seedling heights were unaffected by cotyledon covering or removal. Covering Ulmus americana cotyledons had no significant effect on dry weight increment of stems or foliage or on seedling height. Removal of Ulmus cotyledons from 7-day-old seedlings inhibited dry weight increase of roots, stems, and leaves and inhibited height growth. Removal of Ailanthus cotyledons inhibited dry weight increment of roots, stems, and leaves more than did covering of cotyledons. Species varied greatly in cotyledon development and response to light intensity. Cotyledon size was affected by light intensity in Robinia, but not in Betula or Acer. Responses of cotyledons to light intensity differed from those of foliage leaves. Cotyledon photosynthesis appeared to have a very important role in seedling growth in Robinia and Ailanthus and a less important role in Ulmus.

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