Forest Fragmentation and Seed Germination of Native Species from the Chaco Serrano Forest

Abstract Animal dispersers are essential for many non-native plants since they facilitate seed movement and might promote seed germination and seedling establishment, thereby increasing their chances of invasion. This chapter reviews the published literature on seed dispersal of non-native plant species by native and/or non-native animals. The following questions are addressed: (i) Are interactions between non-native plants and their animal dispersers evenly studied worldwide? (ii) Which are the distinctive traits (i.e. geographical origin, life form, dispersal strategy and propagule traits) of non-native plants that are dispersed by animals? (iii) Which are the most studied groups of dispersers of non-native plants around the world? (iv) Does the literature provide evidence for the Invasional Meltdown Hypothesis (non-native plant-non-native disperser facilitation)? (v) What is the role of animal dispersers at different stages of the non-native plant regeneration process? Our dataset of 204 articles indicates that geographical distribution of the studies was highly heterogeneous among continents, with the highest number coming from North America and the lowest from Asia and Central America. Most of the non-native plants involved in dispersal studies were woody species from Asia with fleshy fruits dispersed by endozoochory. More than the half of the animal dispersal agents noted were birds, followed by mammals, ants and reptiles. The dominance of bird-dispersal interactions over other animal groups was consistent across geographical regions. Although most of the studies involved only native dispersers, interactions among non-native species were detected, providing support for the existence of invasional meltdown processes. Of the total number of reviewed articles reporting seed removal, 74% evaluated seed dispersal, but only a few studies included seed germination (35.3%), seedling establishment (5.4%) or seed predation (23.5%). Finally, we discuss some research biases and directions for future studies in the area.

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Differences in seed properties and germination between native and introduced populations of Triadica sebifera

Journal of Plant Ecology ◽

10.1093/jpe/rtz048 ◽

2019 ◽

Vol 13 (1) ◽

pp. 70-77 ◽

Cited By ~ 1

Author(s):

Jialiang Zhang ◽

Evan Siemann ◽

Baoliang Tian ◽

Wei Huang ◽

Jianqing Ding

Keyword(s):

United States ◽

Seed Germination ◽

Soluble Protein ◽

Native Species ◽

Seed Mass ◽

The United States ◽

Invasion Success ◽

Native Range ◽

Triadica Sebifera ◽

Introduced Range

Abstract Aims Seeds of many invasive plants germinate more quickly than those of native species, likely facilitating invasion success. Assessing the germination traits and seed properties simultaneously for introduced and native populations of an invasive plant is essential to understanding biological invasions. Here, we used Triadica sebifera as a study organism to examine intraspecific differences in seed germination together with seed characteristics. Methods We measured physical (volume, mass, coat hardness and coat thickness of seeds) and chemical (crude fat, soluble protein, sugar, gibberellins [GA] and abscisic acid [ABA] of kernels) properties of T. sebifera seeds collected in 2017 from 12 introduced (United States) populations and 12 native (China) populations and tested their germination rates and timing in a greenhouse experiment in China. Furthermore, we conducted an extra experiment in the United States using seeds collected in 2016 and 2017 to compare the effects of study sites (China vs. United States) and seed collection time (2016 vs. 2017) on seed germination. Important Findings Seeds from the introduced range germinated faster than those from the native range. Physical and chemical measurements showed that seeds from the introduced range were larger, had higher GA concentrations and GA:ABA ratio, but lower crude fat concentrations compared to those from the native range. There were no significant differences in seed mass, coat hardness and coat thickness or kernel ABA, soluble protein or sugar concentrations between seeds from introduced vs. native ranges. Germination rates were correlated between United States and China greenhouses but germination rates for populations varied between collection years. Our results suggest that larger seeds and higher GA likely contribute to faster germination, potentially facilitating T. sebifera invasion in the introduced range.

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Potential Phytotoxic Effect of Essential Oil of Non-Native Species Impatiens parviflora DC.

Plants ◽

10.3390/plants8070241 ◽

2019 ◽

Vol 8 (7) ◽

pp. 241 ◽

Cited By ~ 3

Author(s):

Jana Jurová ◽

Martina Matoušková ◽

Anna Wajs-Bonikowska ◽

Danuta Kalemba ◽

Marek Renčo ◽

...

Keyword(s):

Seed Germination ◽

Essential Oil ◽

Plant Species ◽

Native Species ◽

Root Elongation ◽

Invasive Plant ◽

Main Compound ◽

Impatiens Parviflora ◽

Phytotoxic Effect ◽

Dicot Species

Impatiens parviflora is non-native invasive plant species occupying large areas all over the Europe and threatens native communities by altering their species composition and reducing native biodiversity. The factor responsible for its spreading could be explained by releasing biochemical to the environment. On the other hands, high demand on secondary metabolites as potential source of new ecofriendly biocides could be beneficial. The analysis of I. parviflora essential oil (EO) led us to identify more than 60 volatiles. The main compound was hexahydrofarnesyl acetone, other dominant components were phytol, carvacrol, germacra-4(15),5,10(14)-trien-1-α-ol, and pentacosane. The potential phytotoxic effect of I. parviflora EO collected in two vegetation periods (summer and autumn) was evaluated on seed germination and root elongation of three dicot species (Raphanus sativus, Lepidum sativum, and Lactuca sativa) and on one monocot species (Triticum aestivum). The seed germination of only one dicot species, L. sativa, was affected by both EOs. In contrast, seed germination of monocot species T. aestivum was influenced only by the highest doses of EOs isolated from I. parviflora in autumn. The root elongation of tested plant species was less influenced by I. parviflora EOs. L. sativum showed sensitivity to one dose of EOs hydrodistilled in summer, while the monocot species was influenced by both EOs samples in highest doses. Our findings revealed that I. parviflora contained phenolics that were phytotoxic to the germination of some plant species, mainly at higher EOs doses, while root elongation of tested plants was not suppressed by essential oils.

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Seed Germination of selected Taxa from Kachchh Desert, India

Notulae Scientia Biologicae ◽

10.15835/nsb223692 ◽

2010 ◽

Vol 2 (2) ◽

pp. 41-45 ◽

Cited By ~ 1

Author(s):

Vinay Madhukar RAOLE ◽

Aruna Girish JOSHI ◽

Sandhya Kiran GARGE ◽

Rinku Jitendrakumar DESAI

Keyword(s):

Seed Germination ◽

Growth Regulators ◽

Seed Coat ◽

Native Species ◽

Arid Regions ◽

Conservation Status ◽

Storage Period ◽

The Other ◽

Viable Seeds ◽

Semi Arid

The district of Kachchh contains many culturally important plants. However, their conservation status is little known due to direct and indirect human activities. This study was undertaken with the aim of contributing to the conservation of the native species of these semi-arid regions through germination trials under laboratory conditions. Mature fruits of ten selected species were collected randomly from the known habitats to obtain viable seeds. These seeds were pre-treated with growth regulators singly or in combination after acid scarification or without scarification. Seeds were found to be dormant due to presence of thick seed coat or due to low level of endogenous hormonal level. Most of these seeds required different storage period to mature. Only seeds of Capparis cartilaginea germinated without treatment while the other species required treatments. Addition of growth regulators has enhanced seed germination in few taxa singly and in some plant cases in combination.

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The combined treatments of Canada goldenrod leaf extracts and cadmium pollution confer an inhibitory effect on seed germination and seedling development of lettuce

Australian Journal of Botany ◽

10.1071/bt18046 ◽

2018 ◽

Vol 66 (4) ◽

pp. 331 ◽

Cited By ~ 11

Author(s):

Congyan Wang ◽

Kun Jiang ◽

Bingde Wu ◽

Jiawei Zhou

Keyword(s):

Heavy Metals ◽

Invasive Species ◽

Seed Germination ◽

Native Species ◽

Inhibitory Effect ◽

Seedling Development ◽

Combined Treatments ◽

High Concentration ◽

Leaf Extracts ◽

Allelopathic Effects

Increasing levels of heavy metals are released into ecosystems. The influence of heavy metal pollution on successful invasive species has raised considerable interest, particularly regarding potential allelopathic effects on seed germination and seedling development of native species. Adding heavy metals may alter or even enhance such allelopathic effects of invasive species. The aim of the present study was to address the combined treatments of the invasive species Canada goldenrod (Solidago canadensis L.) leaf extracts and cadmium (Cd) pollution on seed germination and seedling development of the homologous native species lettuce (Lactuca sativa L.). Results showed that the combined treatments of Canada goldenrod leaf extracts and Cd pollution significantly decreased seed germination and seedling development of lettuce compared with the control. In addition, the indices of allelopathic effects for all seed germination and seedling development indices of lettuce were less than zero under the combined treatments of high concentration of Canada goldenrod leaf extracts and Cd pollution (regardless of concentration). Thus, the combined treatments of high concentration of Canada goldenrod leaf extracts and Cd pollution pose an inhibitory effect on seed germination and seedling development of lettuce. Further, the combined treatments of high concentration of Canada goldenrod leaf extracts and Cd pollution (regardless of concentration) cause more toxic effects than the combined treatments of low concentration of Canada goldenrod leaf extracts and Cd pollution (regardless of concentration) on all seed germination and seedling development indices of lettuce. Thus, the inhibitory effects of Canada goldenrod on the seed germination and seedling development of co-occurring native species may be intensified at heavy invasion degrees under increased heavy metal pollution. Subsequently, the competitiveness and fitness of native species may be notably decreased via the reduced seed germination and seedling development and then the notorious invader can establish progressively-growing populations in the colonised ecosystems.

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Effect of Aqueous Leaf Extract of Parthenium hysterophorus L. on the Germination and Shoot Growth of Two Native Species

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.726-731.4348 ◽

2013 ◽

Vol 726-731 ◽

pp. 4348-4351 ◽

Cited By ~ 1

Author(s):

Gang Hu ◽

Zhong Hua Zhang ◽

Bao Qing Hu

Keyword(s):

Seed Germination ◽

Native Species ◽

Shoot Growth ◽

Southern China ◽

Parthenium Hysterophorus ◽

Native Plant ◽

Leaf Extracts ◽

Allelopathic Potential ◽

Plantago Asiatica ◽

The Impact

In order to evaluate the allelopathic potential of an exotic invasive weed,Parthenium hysterophorusL., the effect of different concentrations of aqueous extracts (5%, 25%, 50%, 75% and 100%) prepared from leaves ofP. hysterophoruswere studied on the seed germination and seedling shoot growth of two common native herbs,Plantago asiaticaL. andYoungia japonica(L.) DC., through laboratory bioassays. The aqueous leaf extracts at the concentrations of 25%, 75% and 100% significantly inhibited the seed germination and seedling shoot growth of two target species. There was complete failure of seed germination ofY. japonicain 75% and 100% aqueous leaf extracts. The inhibitory effect increased with increasing extract concentration. These results suggested that allelopathy may play a role in the impact ofP. hysterophorusinvasion on native plant recruitment of invaded communities in southern China.

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Overcoming Dormancy and Influence of Light on the Physiological Quality of Senna cana (Fabaceae) Seeds

Journal of Experimental Agriculture International ◽

10.9734/jeai/2019/v32i530116 ◽

2019 ◽

pp. 1-9

Author(s):

Jordânia X. Medeiros ◽

Ana L. P. Feliciano ◽

Valderez P. Matos ◽

Girlânio H. Silva ◽

Yana S. Lopes ◽

...

Keyword(s):

Seed Germination ◽

Seed Dormancy ◽

Native Species ◽

Red Light ◽

Distilled Water ◽

Light Regimes ◽

Germination Process ◽

Physiological Quality ◽

Mean Germination Time

Environmental factors affect the germination process, like the presence of seed coat and the quality of light; these informations are still scarce for many native species from Brazil, especially for Senna cana, which there are no adequate standards and methodologies to be used in germination tests. The aim of this research was to recommend adequate pre-germinative treatment(s) to overcome seed dormancy, and determine the degree of influence of different light regimes in seed germination of S. cana. Two experiments were carried out: T1-evaluation of different methods of dormancy overcoming (intact seeds (control), T2-imbibition of the intact seeds for 24 hours (in distilled water), T3-scarified seeds with sandpaper n° 100 in the hilum opposite region, T4-scarified seeds with sandpaper n° 100 in the region the hilo opposite region and imbibition in water (in distilled water) for 24 hours; T5-imbibition in water at 80°C); 2-Influence of light quality on seed germination and vigor (white light, red light, far red light and absence of light). The evaluated parameters were: first germination count, percentage of germination, IVG (Germination speed index), MGT (Mean germination time). Treatments were compared by Tukey at 5% probability. The best method for overcoming seed dormancy was mechanical scarification with sandpaper nº 100. The germination of the seeds of S. cana can be classified as indifferent to the luminosity, despite germinative response be greater under white and red light.

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Seed dispersal and site characteristics influence germination and seedling survival of the invasive liana Euonymus fortunei (wintercreeper) in a rural woodland

Canadian Journal of Forest Research ◽

10.1139/cjfr-2018-0212 ◽

2018 ◽

Vol 48 (11) ◽

pp. 1343-1350 ◽

Cited By ~ 1

Author(s):

Todd J. Rounsaville ◽

Carol C. Baskin ◽

Eric Roemmele ◽

Mary A. Arthur

Keyword(s):

Species Diversity ◽

Seed Germination ◽

Native Species ◽

Slow Rate ◽

Seedling Survival ◽

Soil Nutrient ◽

Rate Of Spread ◽

Site Characteristics ◽

Euonymus Fortunei

The invasive liana Euonymus fortunei (Turcz.) Hand.-Maz. (wintercreeper) is an emerging invader that through monodominance of woodlands can drastically reduce native species diversity and alter nutrient cycling. We studied how the vegetation and soils of invaded (INV), “native” (NAT), and wintercreeper removal (REM) site treatments influenced seed germination and seedling survival of this invader. The effect of aril (with vs. without) was also tested for wintercreeper seeds under field and in vitro conditions as a proxy for gravity vs. animal dispersal of seed, respectively. Germination was significantly delayed for seeds sown with an aril (vs. without), as well as those sown in INV soils (vs. NAT or REM), but neither site nor aril affected total germination. The proportion of germinated seedlings that survived after the first winter was significantly different based on site (p = 0.054) and aril (p = 0.071) treatments, with lower survival resulting from seeds sown without arils, and for seeds sown in INV sites. Magnesium (Mg) concentrations were significantly higher among INV soils (vs. NAT) and provide further support that wintercreeper is a driver of soil nutrient change. Our findings that aril-enclosed (gravity-dispersed) seeds yielded greater survival, despite being locally dispersed within invaded sites (where survival was lowest), support the historically slow rate of spread for this species.

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Phytotoxicity of exotic plants on the physiological potential of seeds of native species of caatinga

Revista Agro mbiente On-line ◽

10.18227/1982-8470ragro.v12i2.4884 ◽

2018 ◽

Vol 12 (2) ◽

pp. 134 ◽

Cited By ~ 1

Author(s):

Silvana Fraga Silva ◽

Halina Stéffany Lopes Costa ◽

Jesimiel Silva Viana ◽

Ana Maria Oliveira Ferreira ◽

Diego Sousa Pereira ◽

...

Keyword(s):

Seed Germination ◽

Native Species ◽

Biodiversity Loss ◽

Exotic Plants ◽

Inhibitory Effect ◽

Allelopathic Effect ◽

Native Forest ◽

Aqueous Extracts ◽

Physiological Quality ◽

Invasive Exotic

The introduction of species is one of the major causes of biodiversity loss. Invasive exotic plants adapt, propagate and dominate, damaging both natural processes and native species. Thus, the objective was to evaluate the allelopathic effect of three exotic species in the caatinga, on the physiological quality of native forest seeds. Aqueous extracts of leaves of Azadirachta indica, Prosopis juliflora and Cryptostegia madagascariensis were tested to evaluate their effect on the seed germination and seedling vigor of Piptadenia moniliformis, Mimosa tenuiflora and Mimosa caesalpiniaefolia. Seed germination of M. tenuiflora was inhibited by the aqueous extracts of P. juliflora and A. indica in 100% and 42%, respectively, with a reduced GVI with the extracts of P. juliflora and C. madagascariensis. Regarding AEI, P. juliflora extract had positive effect on P. moniliformis seeds and negative on M. tenuiflora seeds, close to -1. A reduction in height of P. moniliformis was observed when the seedlings were in contact with the extracts of the invasive plants studied. For M. tenuiflora, the extract of P. juliflora prevented the formation of seedlings, and M. caesalpiniaefolia presented higher inhibitory effect with extracts of P. juliflora and A. indica. Therefore, M. tenuiflora showed to be sensitive to P. juliflora phytotoxicity.

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