scholarly journals Dicamba drift alters plant-herbivore interactions at the agro-ecological interface

2021 ◽  
Author(s):  
Nia M Johnson ◽  
Regina S Baucom
Keyword(s):  
Growth Rate ◽  
Herbicide Resistance ◽  
Species Interactions ◽  
Ecosystem Dynamics ◽  
Herbivore Interactions ◽  
Ecological Interface ◽  
Plant Herbivore ◽  
Herbicide Drift ◽  
The Impact ◽  
Herbicide Exposure

Natural populations evolve in response to biotic and abiotic changes in their environment, which shape species interactions and ecosystem dynamics. Agricultural systems can introduce novel conditions via herbicide exposure to non-crop habitats in surrounding fields. While herbicide drift is known to produce a variety of toxic effects in plants, little is known about its impact on non-target wildlife species interactions. In a two-year study, we investigated the impact of herbicide drift on plant-herbivore interactions with common weed velvetleaf (Abutlion theophrasti) as the focal species. The findings reveal a significant increase in the phloem feeding silverleaf whitefly (Bermisia tabaci) abundance on the plants exposed to herbicide at drift rates of 0.5% and 1% of the field dose. Additionally, we found evidence that drift imposes correlated selection on whitefly resistance and growth rate as well as positive linear selection on herbicide resistance. We also identified a significant phenotypic tradeoff between whitefly resistance and herbicide resistance in addition to whitefly resistance and relative growth rate in the presence of dicamba drift. These findings suggest herbicide exposure to non-target communities can significantly alter herbivore populations, potentially impacting biodiversity and community dynamics of weed populations found at the agro-ecological interface.

scholarly journals Relationship of earthworm biomass with temperature and rainfall in cultivated coconut and cinnamon lands in Sri Lanka

2020 ◽  
Vol 25 (50) ◽  
pp. 129-132
Author(s):  
Udaya Wickramasinghe ◽  
R.W.K. Punchihewa ◽  
Shamali Kumari ◽  
Faiz Marikar
Keyword(s):  
Sri Lanka ◽  
Weather Conditions ◽  
Number Of Species ◽  
Significant Difference ◽  
Herbivore Interactions ◽  
Earthworm Biomass ◽  
Cinnamon Soil ◽  
Plant Herbivore ◽  
Relationship Of ◽  
The Impact

Earthworms are keystone detritivores that can influence primary producers by changing seedbed conditions, soil characteristics, flow of water, nutrients and carbon, and plant-herbivore interactions. Our objective was to understand the impact of weather conditions on the number of species found and the relationship between the biomass and temperature and rainfall conditions in cultivated coconut and cinnamon lands in Sri Lanka. Earthworms were collected from Hakmana, Walasmulla, and Deiyandara districts from Sri Lanka. In this study we found a significant relationship between earthworm biomass and temperature in cinnamon soil, but there was no significant difference related to temperature and rainfall in coconut lands compared with cinnamon lands. The correlation between earthworm biomass and rainfall was weak. Also, we found no relationship between the number of species and temperature and rainfall conditions. The results indicated that the number of species was reduced due to climate change and that cinnamon lands provided good conditions for earthworms.

scholarly journals Interaction intimacy organizes networks of antagonistic interactions in different ways

2013 ◽  
Vol 10 (78) ◽  
pp. 20120649 ◽  
Author(s):  
Mathias M. Pires ◽  
Paulo R. Guimarães
Keyword(s):  
Species Interactions ◽  
Assembly Rules ◽  
Major Question ◽  
Predator Prey ◽  
Herbivore Interactions ◽  
Plant Herbivore ◽  
Host Parasite ◽  
Different Levels ◽  
Antagonistic Interactions

Interaction intimacy, the degree of biological integration between interacting individuals, shapes the ecology and evolution of species interactions. A major question in ecology is whether interaction intimacy also shapes the way interactions are organized within communities. We combined analyses of network structure and food web models to test the role of interaction intimacy in determining patterns of antagonistic interactions, such as host–parasite, predator–prey and plant–herbivore interactions. Networks describing interactions with low intimacy were more connected, more nested and less modular than high-intimacy networks. Moreover, the performance of the models differed across networks with different levels of intimacy. All models reproduced well low-intimacy networks, whereas the more elaborate models were also capable of reproducing networks depicting interactions with higher levels of intimacy. Our results indicate the key role of interaction intimacy in organizing antagonisms, suggesting that greater interaction intimacy might be associated with greater complexity in the assembly rules shaping ecological networks.

scholarly journals Root volatiles in plant-plant interactions II: Root terpenes from Centaurea stoebe modify Taraxacum officinale root chemistry and root herbivore growth

2018 ◽  
Author(s):  
Wei Huang ◽  
Valentin Gfeller ◽  
Matthias Erb
Keyword(s):  
Secondary Metabolites ◽  
Taraxacum Officinale ◽  
Plant Interactions ◽  
White Grub ◽  
Centaurea Stoebe ◽  
Primary And Secondary Metabolites ◽  
Herbivore Interactions ◽  
Root Herbivore ◽  
Plant Herbivore ◽  
The Impact

AbstractVolatile organic compounds (VOCs) emitted by plant roots can influence the germination and growth of neighboring plants. However, little is known about the effects of root VOCs on plant-herbivore interactions. The spotted knapeed (Centaurea stoebe) constitutively releases high amounts of sesquiterpenes into the rhizosphere. Here, we examine the impact of C. stoebe root VOCs on primary and secondary metabolites of sympatric Taraxacum officinale plants and the resulting plant-mediated effects on a generalist root herbivore, the white grub Melolontha melolontha. We show that exposure of T. officinale to C. stoebe root VOCs does not affect the accumulation of defensive secondary metabolites, but modulates carbohydrate and total protein levels in T. officinale roots. Furthermore, VOC exposure increases M. melolontha growth on T. officinale plants. Exposure of T. officinale to a major C. stoebe root VOC, the sesquiterpene (E)-β-caryophyllene, partially mimics the effect of the full root VOC blend on M. melolontha growth. Thus, releasing root VOCs can modify plant-herbivore interactions of neighboring plants. The release of VOCs to increase the susceptibility of other plants may be a form of plant offense.

scholarly journals Domestication impacts on plant–herbivore interactions: a meta-analysis

2017 ◽  
Vol 372 (1712) ◽  
pp. 20160034 ◽  
Author(s):  
Susan R. Whitehead ◽  
Martin M. Turcotte ◽  
Katja Poveda
Keyword(s):  
Species Interactions ◽  
Food Systems ◽  
Crop Yields ◽  
Meta Analysis ◽  
Plant Defence ◽  
Reproductive Organs ◽  
Negative Effects ◽  
Theoretical Understanding ◽  
Herbivore Interactions ◽  
Plant Herbivore

For millennia, humans have imposed strong selection on domesticated crops, resulting in drastically altered crop phenotypes compared with wild ancestors. Crop yields have increased, but a long-held hypothesis is that domestication has also unintentionally decreased plant defences against herbivores. To test this hypothesis, we conducted a phylogenetically controlled meta-analysis comparing insect herbivore resistance and putative plant defence traits between crops and their wild relatives. Our database included 2098 comparisons made across 73 crops in 89 studies. We found that domestication consistently reduced plant resistance to herbivores, although the magnitude of the effects varied across plant organs and depended on how resistance was measured. However, domestication had no consistent effects on the specific plant defence traits underlying resistance, including secondary metabolites and physical feeding barriers. The values of these traits sometimes increased and sometimes decreased during domestication. Consistent negative effects of domestication were observed only when defence traits were measured in reproductive organs or in the plant organ that was harvested. These results highlight the complexity of evolution under domestication and the need for an improved theoretical understanding of the mechanisms through which agronomic selection can influence the species interactions that impact both the yield and sustainability of our food systems. This article is part of the themed issue ‘Human influences on evolution, and the ecological and societal consequences’.

The impact of plant chemical diversity on plant–herbivore interactions at the community level

Oecologia ◽  
2016 ◽  
Vol 181 (4) ◽  
pp. 1199-1208 ◽  
Author(s):  
Diego Salazar ◽  
Alejandra Jaramillo ◽  
Robert J. Marquis
Keyword(s):  
Chemical Diversity ◽  
Community Level ◽  
Plant Chemical ◽  
Herbivore Interactions ◽  
Plant Herbivore ◽  
The Impact

scholarly journals Museum specimens provide novel insights into changing plant–herbivore interactions

2018 ◽  
Vol 374 (1763) ◽  
pp. 20170393 ◽  
Author(s):  
Emily K. Meineke ◽  
T. Jonathan Davies
Keyword(s):  
Global Change ◽  
Species Interactions ◽  
Host Plants ◽  
Insect Herbivory ◽  
Individual Species ◽  
Museum Specimens ◽  
Proximate Mechanisms ◽  
Plant Associations ◽  
Herbivore Interactions ◽  
Plant Herbivore

Mounting evidence shows that species interactions may mediate how individual species respond to climate change. However, long-term anthropogenic effects on species interactions are poorly characterized owing to a lack of data. Insect herbivory is a major ecological process that represents the interaction between insect herbivores and their host plants, but historical data on insect damage to plants is particularly sparse. Here, we suggest that museum collections of insects and plants can fill key gaps in our knowledge on changing trophic interactions, including proximate mechanisms and the net outcomes of multiple global change drivers across diverse insect herbivore–plant associations. We outline theory on how global change may affect herbivores and their host plants and highlight the unique data that could be extracted from museum specimens to explore their shifting interactions. We aim to provide a framework for using museum specimens to explore how some of the most diverse co-evolved relationships are responding to climate and land use change. This article is part of the theme issue ‘Biological collections for understanding biodiversity in the Anthropocene’.

scholarly journals Intrinsic ecological dynamics drive biodiversity turnover in model metacommunities

2020 ◽  
Author(s):  
Jacob D. O’Sullivan ◽  
J. Christopher D. Terry ◽  
Axel G. Rossberg
Keyword(s):  
Species Interactions ◽  
Potential Role ◽  
Ecological Status ◽  
Ecosystem Dynamics ◽  
Management Tools ◽  
Spatially Explicit Model ◽  
Ecological Dynamics ◽  
Biodiversity Change ◽  
The Impact

ABSTRACTTurnover of species composition through time is frequently observed in ecosystems. It is often interpreted as indicating the impact of changes in the environment. Continuous turnover due solely to ecological dynamics—species interactions and dispersal—is also known to be theoretically possible, however the prevalence of such autonomous turnover in natural communities remains unclear. Here we demonstrate that observed patterns of compositional turnover and other important macroecological phenomena can be reproduced in large spatially explicit model ecosystems, without external forcing such as environmental change or the invasion of new species into the model. These results imply that the potential role of autonomous turnover as a widespread and important natural process is underappreciated, challenging assumptions implicit in many observation and management tools. Quantifying the baseline level of compositional change would greatly improve ecological status assessments.One Sentence SummaryBiodiversity change previously attributed to external drivers is explainable as resulting from intrinsic ecosystem dynamics.

International trade: Research of the reasons for the fall

2019 ◽  
pp. 79-91 ◽  
Author(s):  
V. S. Nazarov ◽  
S. S. Lazaryan ◽  
I. V. Nikonov ◽  
A. I. Votinov
Keyword(s):  
Growth Rate ◽  
International Trade ◽  
Exchange Rate ◽  
Global Economy ◽  
Structural Changes ◽  
Global Value Chains ◽  
Value Chains ◽  
Negative Contribution ◽  
Basic Commodity ◽  
The Impact

The article assesses the impact of various factors on the growth rate of international trade. Many experts interpreted the cross-border flows of goods decline against the backdrop of a growing global economy as an alarming sign that indicates a slowdown in the processes of globalization. To determine the reasons for the dynamics of international trade, the decompositions of its growth rate were carried out and allowed to single out the effect of the dollar exchange rate, the commodities prices and global value chains on the change in the volume of trade. As a result, it was discovered that the most part of the dynamics of international trade is due to fluctuations in the exchange rate of the dollar and prices for basic commodity groups. The negative contribution of trade within global value chains in 2014 was also revealed. During the investigated period (2000—2014), such a picture was observed only in the crisis periods, which may indicate the beginning of structural changes in the world trade.

Sign in / Sign up

Export Citation Format

Share Document