scholarly journals Allelopathy of Knotweeds as Invasive Plants

Plants ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 3
Author(s):  
Hisashi Kato-Noguchi

Perennial herbaceous Fallopia is native to East Asia, and was introduced to Europe and North America in the 19th century as an ornamental plant. Fallopia has been spreading quickly and has naturalized in many countries. It is listed in the world’s 100 worst alien species. Fallopia often forms dense monospecies stands through the interruption of the regeneration process of indigenous plant species. Allelopathy of Japanese knotweed (Fallopia japonica), giant knotweed (Fallopia sachalinensis), and Bohemian knotweed (Fallopia x bohemica) has been reported to play an essential role in its invasion. The exudate from their roots and/or rhizomes, and their plant residues inhibited the germination and growth of some other plant species. These knotweeds, which are non-mycorrhizal plants, also suppressed the abundance and species richness of arbuscular mycorrhizal fungi (AMF) in the rhizosphere soil. Such suppression was critical for most territorial plants to form the mutualism with AMF, which enhances the nutrient and water uptake, and the tolerance against pathogens and stress conditions. Several allelochemicals such as flavanols, stilbenes, and quinones were identified in the extracts, residues, and rhizosphere soil of the knotweeds. The accumulated evidence suggests that some of those allelochemicals in knotweeds may be released into the rhizosphere soil through the decomposition process of their plant parts, and the exudation from their rhizomes and roots. Those allelochemicals may inhibit the germination and growth of native plants, and suppress the mycorrhizal colonization of native plants, which provides the knotweeds with a competitive advantage, and interrupts the regeneration processes of native plants. Therefore, allelopathy of knotweeds may contribute to establishing their new habitats in the introduced ranges as invasive plant species. It is the first review article focusing on the allelopathy of knotweeds.

Plants ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 1028
Author(s):  
Hisashi Kato-Noguchi ◽  
Denny Kurniadie

Lantana camara L. (Verbenaceae) is native to tropical America and has been introduced into many other countries as an ornamental and hedge plant. The species has been spreading quickly and has naturalized in more than 60 countries as an invasive noxious weed. It is considered to be one of the world’s 100 worst alien species. L. camara often forms dense monospecies stands through the interruption of the regeneration process of indigenous plant species. Allelopathy of L. camara has been reported to play a crucial role in its invasiveness. The extracts, essential oil, leachates, residues, and rhizosphere soil of L. camara suppressed the germination and growth of other plant species. Several allelochemicals, such as phenolic compounds, sesquiterpenes, triterpenes, and a flavonoid, were identified in the extracts, essential oil, residues, and rhizosphere soil of L. camara. The evidence also suggests that some of those allelochemicals in L. camara are probably released into the rhizosphere soil under the canopy and neighboring environments during the decomposition process of the residues and as leachates and volatile compounds from living plant parts of L. camara. The released allelochemicals may suppress the regeneration process of indigenous plant species by decreasing their germination and seedling growth and increasing their mortality. Therefore, the allelopathic property of L. camara may support its invasive potential and formation of dense monospecies stands.


2014 ◽  
Vol 35 (1) ◽  
pp. 3-23 ◽  
Author(s):  
Mariusz Tadych ◽  
Janusz Błaszkowski

The occurrence of arbuscular mycorrhizal fungi (AMF) associated with 19 plant species from 12 families growing in the Brda river valley in the Tuchola Forests is presented. The most frequently investigated plans were those from the families <i>Cupressaceae</i> and <i>Plantaginaceae</i>. Examination of trap cultures established from rhizosphere soil-root mixtures of the plans sampled revealed 20 described species of AMF, two undescribed <i>Glomus</i> spp., and three species of the genus <i>Glomus</i> that were difficult to recognize. The dominating AMF were members of the genus <i>Glomus</i>. Among the AMF found, <i>G. claroideum</i> was present, a species recorded for the first time in Poland. The distribution in Poland and in the world of the AMF encountered is shown.


2013 ◽  
Vol 55 (1) ◽  
pp. 41-48
Author(s):  
Janusz Błaszczykowski ◽  
Anna Iwaniuk ◽  
Beata Czerniawska

The occurrence of arbuscular mycorrhizal fungi (AMF) in cultivated soils of Poland was characterized based on 15-year investigations. Spores of AMF were isolated from both field-collected root-rhizosphere soil mixtures and trap cultures established with a part of these mixtures. The mixtures were collected from under 41 plant species. The plant species most frequently sampled were <i>Hordeum vulgare, Triticum aestivum</i>, and <i>Zea mays</i>. Spores of AMF were found in 97,5% of the field-collected root-soil samples and in 95,5% of trap cultures. The AMF predominating in populations of the spores revealed were members of the genus <i>Glomus</i>. The spores recovered belonged to 36 species. The AM fungal species most frequently occurring in cultivated soils of Poland were <i>Glomus caledonium, G.constrictum, G.deserticola</i>, and <i>G.mosseae</i>.


Web Ecology ◽  
2018 ◽  
Vol 18 (1) ◽  
pp. 105-114 ◽  
Author(s):  
Pedro Carvalho ◽  
Rui Martins ◽  
António Portugal ◽  
M. Teresa Gonçalves

Abstract. Maritime pine forests are a major ecosystem throughout the Portuguese coast and are severely affected by the invasion of Acacia longifolia. The presented study investigated the diversity of ectomycorrhizal fungi (ECM) of major plant species in these ecosystems to find possible links between Pinus pinaster, three native Cistaceae shrubs and the Acacia invasive species. We successfully identified 13 ECM fungal taxa. Within those, two species from the order Helotiales were found in all plant species, and over half of the fungal ECM species found in Pinus pinaster were also common to the Cistaceae shrubs. Network analysis points to the Cistaceae shrubs having a central role in these below-ground communities, therefore enforcing the idea that they are key to these communities and should not be underestimated. Our results also point to the evolving role of invasive plant species in the ecosystem dynamics in the rhizosphere, which host fungal species that are common to native plants, although it is not yet clear whether these fungal taxa are native or a consequence of the presence of Acacia longifolia.


2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Anurag Chaturvedi ◽  
Joaquim Cruz Corella ◽  
Chanz Robbins ◽  
Anita Loha ◽  
Laure Menin ◽  
...  

AbstractEarly-diverging fungi (EDF) are distinct from Dikarya and other eukaryotes, exhibiting high N6-methyldeoxyadenine (6mA) contents, rather than 5-methylcytosine (5mC). As plants transitioned to land the EDF sub-phylum, arbuscular mycorrhizal fungi (AMF; Glomeromycotina) evolved a symbiotic lifestyle with 80% of plant species worldwide. Here we show that these fungi exhibit 5mC and 6mA methylation characteristics that jointly set them apart from other fungi. The model AMF, R. irregularis, evolved very high levels of 5mC and greatly reduced levels of 6mA. However, unlike the Dikarya, 6mA in AMF occurs at symmetrical ApT motifs in genes and is associated with their transcription. 6mA is heterogeneously distributed among nuclei in these coenocytic fungi suggesting functional differences among nuclei. While far fewer genes are regulated by 6mA in the AMF genome than in EDF, most strikingly, 6mA methylation has been specifically retained in genes implicated in components of phosphate regulation; the quintessential hallmark defining this globally important symbiosis.


2021 ◽  
Author(s):  
Maede Faghihinia ◽  
Yi Zou ◽  
Yongfei Bai ◽  
Martin Dudáš ◽  
Rob Marrs ◽  
...  

Abstract Arbuscular mycorrhizal fungi (AMF) are the predominant type of mycorrhizal fungi in roots and rhizosphere soil of grass species worldwide. Grasslands are currently experiencing increasing grazing pressure, but it is not yet clear how grazing intensity and host plant grazing preference by large herbivores interact with soil- and root-associated AMF communities. Here, we tested whether the diversity and community composition of AMF in the roots and rhizosphere soil of two dominant perennial grasses grazed differently by livestock change in response to grazing intensity. We conducted a study in a long-term field experiment in which seven levels of field-manipulated grazing intensities were maintained for 13 years in a typical steppe grassland in northern China. We extracted DNA from the roots and rhizosphere soil of two dominant grasses, Leymus chinense (Trin.) Tzvel. and Stipa grandis P. Smirn, with contrasting grazing preference by sheep. AMF DNA from root and soil samples were then subjected to molecular analysis. Our results showed that AMF α-diversity (richness) at the virtual taxa (VT) level varied as a function of grazing intensity. Different VTs showed completely different responses along the gradient, one increasing, one decreasing and others showing no response. Glomeraceae was the most abundant AMF family along the grazing gradient, which fits well with the theory of disturbance tolerance of this group. In addition, sheep grazing preference for host plants did not explain a considerable variation in AMF α-diversity. However, the two grass species exhibited different community composition in their roots and rhizosphere soils. Roots exhibited a lower α-diversity and higher β-diversity within the AMF community than soils. Overall, our results suggest that long-term grazing intensity might have changed the abundance of functionally-diverse AMF taxa in favor of those with disturbance-tolerant traits. We suggest our results would be useful in informing the choice of mycorrhizal fungi indicator variables when assessing the impacts of grassland management choices on grassland ecosystem functioning.


2020 ◽  
Vol 7 (2) ◽  
pp. 30-38
Author(s):  
Santhoshkumar S ◽  
Nagarajan N ◽  
Sree Priya S

In the present study to analyzed that the arbuscular mycorrhizal fungal spores in root colonization and spore population in rhizosphere soils samples in various medicinal at Paithal hills,Western Ghats of Kannur district, Kerala, India. Root and rhizosphere soil samples were collected during the month of August, 2018-March, 2019 from the surface to 30 cm depth as well as pH were also recorded. Totally 30 plant species belonging to 19 families were collected and identified. The present result showed arbuscular mycorrhizal spore population in the rhizosphere soil and root colonization of all the plant species. A total of 19 AM fungal spores were recovered from the rhizosphere soil samples in this study region. The Glomus was dominant had seen in rhizosphere soil samples in all the medicinal plant species. The maximum spore population was found in the rhizosphere soil samples of Mimosa pudica (590/100g of soil) which belongs to the family Mimosaceae and the lowest spore population was observed in the Terminalia bellirica 135/100g of soil) belongs to Combretaceae family. The highest  78 % AM fungal colonization was found in roots of Euphorbia hirta belongs to the family Euphorbiaceae. While the lowest 11 % AM fungal colonization was found in the root of Sida acuta belongs to the family Malvaceae.


Sign in / Sign up

Export Citation Format

Share Document