Facilitation promotes plant invasions and indirect negative interactions

A new method for the quantitative analysis of multiple toxicity data is described and illustrated using a data set on metal exposure to copepods. Positive interactions are observed for Ni-Pb and Pb-Cr, with weak negative interactions observed for Ni-Cr.

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The alien flora of Sudan and South Sudan: taxonomic and biogeographical composition

Biological Invasions ◽

10.1007/s10530-021-02495-7 ◽

2021 ◽

Author(s):

Ali Omer ◽

Maha Kordofani ◽

Haytham H. Gibreel ◽

Petr Pyšek ◽

Mark van Kleunen

Keyword(s):

Alien Species ◽

South Sudan ◽

Plant Invasions ◽

Life Forms ◽

Alien Plants ◽

African Countries ◽

Alien Flora ◽

Result Show ◽

Perennial Herbs ◽

Disturbed Habitats

AbstractStudies on plant invasions depend on local and regional checklists of the alien flora. However, global overview studies have shown that some regions, including many African countries, remain understudied in this regard. To contribute to filling this gap, here we present the first checklist of alien plants of Sudan and South Sudan (the Sudans). We analysed the taxonomic and geographical composition of the species on this list. Our result show that of the 113 alien species in Sudans (99 in Sudan and 59 in South Sudan), 92 (81.4%) are naturalized and 21 (18.6%) are just casual aliens. The number of naturalized species represent 2.2% of the total flora of the Sudans (4096). The alien species belong to 44 families and 85 genera, and many of them are native to Southern America and Northern America (85.8%). Annual and perennial herbs are the prevailing life forms in the alien flora of the Sudans (68.1%), and, among the casual species, perennial herbs are underrepresented whereas woody tree species are over-represented. Alien plants of the Sudans are mostly used for medicinal and environmental purposes globally. The naturalized plants predominantly occur in man-made disturbed habitats, such as agricultural and ruderal habitats. This first overview of the alien flora of the Sudans should stimulate further research and recording of the alien flora to better understand the drivers and consequences of alien plants in the Sudans.

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Impact of MASP2 gene polymorphism and gene-tea drinking interaction on susceptibility to tuberculosis

Scientific Reports ◽

10.1038/s41598-021-86129-x ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Zihao Li ◽

Mian Wang ◽

Hua Zhong ◽

Xin Huang ◽

Xinyin Wu ◽

...

Keyword(s):

Additive Model ◽

Lectin Pathway ◽

Control Group ◽

Single Nucleotide ◽

Key Enzyme ◽

Healthy Control ◽

Tea Drinking ◽

Mannan Binding Lectin ◽

The Complement System ◽

Negative Interactions

AbstractMannan-binding lectin-associated serine protease-2 (MASP-2) has been reported to play an important role as a key enzyme in the lectin pathway of the complement system. The objectives of our study were to determine whether the single-nucleotide polymorphism (SNPs) of MASP2 and the gene-tea drinking interaction were associated with the susceptibility to TB. In total, 503 patients and 494 healthy controls were contained. Three SNPs (rs12142107, rs12711521, and rs7548659) were genotyped. The association between the SNPs and susceptibility to TB were investigated by conducting multivariate unconditional logistic regression analysis. The gene-tea drinking interactions were analyzed by the additive model of marginal structural linear odds models. Both genotype AC + AA at rs12711521 of MASP2 genes and genotype GT + GG at rs7548659 of MASP2 genes were more prevalent in the TB patient group than the healthy control group (OR: 1.423 and 1.439, respectively, P < 0.05). In addition, The relative excess risk of interaction (RERI) between tea drinking and rs12142107, rs12711521, and rs7548659 of MASP2 genes was found to suggest negative interactions, which reached − 0.2311 (95% confidence interval (CI): − 0.4736, − 0.0113), − 0.7080 (95% CI − 1.3998, − 0.0163), and − 0.5140 (95% CI − 0.8988, − 0.1291), respectively (P < 0.05). Our finding indicated that the SNPs (rs12711521 and rs7548659) of MASP2 were associated with the susceptibility to TB. Furthermore, there were negative interactions between tea drinking and rs12142107, rs12711521, and rs75548659 of MASP2 gene, respectively. Our research provides a basis for studying the pathogenesis and prevention of tuberculosis.

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Impacts of plant invasions in native plant‐pollinator networks

New Phytologist ◽

10.1111/nph.17339 ◽

2021 ◽

Author(s):

Víctor Parra‐Tabla ◽

Gerardo Arceo‐Gómez

Keyword(s):

Plant Invasions ◽

Native Plant ◽

Plant Pollinator

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Factors influencing the occurrence of negative interactions between people and crocodilians in Mexico

Oryx ◽

10.1017/s0030605319000668 ◽

2021 ◽

pp. 1-9

Author(s):

Giovany Arturo González-Desales ◽

Luis Sigler ◽

Jesús García-Grajales ◽

Pierre Charruau ◽

Martha Mariela Zarco-González ◽

...

Keyword(s):

Anthropogenic Activities ◽

Biosphere Reserve ◽

Rigorous Evaluation ◽

Caiman Crocodilus ◽

Crocodylus Acutus ◽

American Crocodile ◽

Nesting Sites ◽

The Relationship ◽

Nesting Season ◽

Negative Interactions

Abstract Negative interactions between people and crocodilians have increased worldwide, but in Mexico there have been few systematic reports and no rigorous evaluation of this problem. We compiled information on negative interactions between people and the spectacled caiman Caiman crocodilus and American crocodile Crocodylus acutus from the Worldwide Crocodilian Attack Database for 1993–2018, and we investigated interactions in greater depth, through interviews with people in La Encrucijada Biosphere Reserve. We examined the relationship between the occurrence of negative interactions between people and C. acutus and the species' nesting season and abundance, and presence records. In Mexico, the frequency of negative interactions increases when anthropogenic activities occur close to nesting sites (< 30 km) and during the nesting season (February–September). In La Encrucijada, following negative interactions with crocodiles, the local inhabitants killed 30 crocodiles measuring > 2.5 m long in 2011–2012. The frequency of negative human–crocodilian interactions was not correlated with the abundance of crocodilians but was correlated with the number of presence records of crocodiles. Strategies to minimize these interactions include warnings at nesting sites, increased monitoring of anthropogenic activities during the nesting season, and management of nests to prevent them being destroyed by people.

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The role of host promiscuity in the invasion process of a seaweed holobiont

The ISME Journal ◽

10.1038/s41396-020-00878-7 ◽

2021 ◽

Author(s):

Guido Bonthond ◽

Till Bayer ◽

Stacy A. Krueger-Hadfield ◽

Nadja Stärck ◽

Gaoge Wang ◽

...

Keyword(s):

Microbial Communities ◽

Beta Diversity ◽

Common Garden ◽

Plant Invasions ◽

Invasion Process ◽

Microbial Succession ◽

Invasive Seaweed ◽

Native Populations ◽

Important Trait ◽

Different Populations

AbstractInvasive species are co-introduced with microbiota from their native range and also interact with microbiota found in the novel environment to which they are introduced. Host flexibility toward microbiota, or host promiscuity, is an important trait underlying terrestrial plant invasions. To test whether host promiscuity may be important in macroalgal invasions, we experimentally simulated an invasion in a common garden setting, using the widespread invasive macroalga Agarophyton vermiculophyllum as a model invasive seaweed holobiont. After disturbing the microbiota of individuals from native and non-native populations with antibiotics, we monitored the microbial succession trajectories in the presence of a new source of microbes. Microbial communities were strongly impacted by the treatment and changed compositionally and in terms of diversity but recovered functionally by the end of the experiment in most respects. Beta-diversity in disturbed holobionts strongly decreased, indicating that different populations configure more similar –or more common– microbial communities when exposed to the same conditions. This decline in beta-diversity occurred not only more rapidly, but was also more pronounced in non-native populations, while individuals from native populations retained communities more similar to those observed in the field. This study demonstrates that microbial communities of non-native A. vermiculophyllum are more flexibly adjusted to the environment and suggests that an intraspecific increase in host promiscuity has promoted the invasion process of A. vermiculophyllum. This phenomenon may be important among invasive macroalgal holobionts in general.

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