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

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.

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The Multifunctional Roles of Polyphenols in Plant-Herbivore Interactions

International Journal of Molecular Sciences ◽

10.3390/ijms22031442 ◽

2021 ◽

Vol 22 (3) ◽

pp. 1442

Author(s):

Sukhman Singh ◽

Ishveen Kaur ◽

Rupesh Kariyat

Keyword(s):

Secondary Metabolites ◽

Biologically Active ◽

Future Research ◽

Plant Interactions ◽

Plant Insect Interactions ◽

Physical Defenses ◽

Herbivore Interactions ◽

Insect Interactions ◽

Plant Herbivore

There is no argument to the fact that insect herbivores cause significant losses to plant productivity in both natural and agricultural ecosystems. To counter this continuous onslaught, plants have evolved a suite of direct and indirect, constitutive and induced, chemical and physical defenses, and secondary metabolites are a key group that facilitates these defenses. Polyphenols—widely distributed in flowering plants—are the major group of such biologically active secondary metabolites. Recent advances in analytical chemistry and metabolomics have provided an opportunity to dig deep into extraction and quantification of plant-based natural products with insecticidal/insect deterrent activity, a potential sustainable pest management strategy. However, we currently lack an updated review of their multifunctional roles in insect-plant interactions, especially focusing on their insect deterrent or antifeedant properties. This review focuses on the role of polyphenols in plant-insect interactions and plant defenses including their structure, induction, regulation, and their anti-feeding and toxicity effects. Details on mechanisms underlying these interactions and localization of these compounds are discussed in the context of insect-plant interactions, current findings, and potential avenues for future research in this area.

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A beta-glucosidase of an insect herbivore determines both toxicity and deterrence of a dandelion defense metabolite

10.1101/2021.03.22.436380 ◽

2021 ◽

Author(s):

Meret Huber ◽

Thomas Roder ◽

Sandra Irmisch ◽

Alexander Riedel ◽

Saskia Gablenz ◽

...

Keyword(s):

Plant Defense ◽

Feeding Preference ◽

Melolontha Melolontha ◽

Herbivore Interactions ◽

The Common ◽

Common Dandelion ◽

Beta Glucosidase ◽

Insect Gut ◽

Root Herbivore ◽

Plant Herbivore

Gut enzymes can metabolize plant defense metabolites and thereby affect the growth and fitness of insect herbivores. Whether these enzymes also influence herbivore behavior and feeding preference is largely unknown. We studied the metabolization of taraxinic acid β-D-glucopyranosyl ester (TA-G), a sesquiterpene lactone of the common dandelion (Taraxacum officinale) that deters its major root herbivore, the common cockchafer larva (Melolontha melolontha). We demonstrate that TA-G is rapidly deglycosylated and conjugated to glutathione in the insect gut. A broad-spectrum M. melolontha β-glucosidase, Mm_bGlc17, is sufficient and necessary for TA-G deglycosylation. Using plants and insect RNA interference, we show that Mm_bGlc17 reduces TA-G toxicity. Furthermore, Mm_bGlc17 is required for the preference of M. melolontha larvae for TA-G deficient plants. Thus, herbivore metabolism modulates both the toxicity and deterrence of a plant defense metabolite. Our work illustrates the multifacteted roles of insect digestive enzymes as mediators of plant-herbivore interactions.

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Divergent selection for secondary metabolites between wild populations of Brassica oleracea and its implications for plant-herbivore interactions

Heredity ◽

10.1038/hdy.1995.164 ◽

1995 ◽

Vol 75 (5) ◽

pp. 472-484 ◽

Cited By ~ 89

Author(s):

R Mithen ◽

A F Raybould ◽

A Giamoustaris

Keyword(s):

Secondary Metabolites ◽

Brassica Oleracea ◽

Divergent Selection ◽

Wild Populations ◽

Herbivore Interactions ◽

Selection For ◽

Plant Herbivore

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Regulation of Plant Phenolic Synthesis: From Biochemistry to Ecology and Evolution

Australian Journal of Botany ◽

10.1071/bt9960613 ◽

1996 ◽

Vol 44 (6) ◽

pp. 613 ◽

Cited By ~ 57

Author(s):

M Matsuki

Keyword(s):

Cell Differentiation ◽

Phenolic Compounds ◽

Secondary Metabolites ◽

Selection Pressure ◽

Uv Light ◽

Interdisciplinary Studies ◽

Cell Type ◽

Microbial Infection ◽

Herbivore Interactions ◽

Plant Herbivore

The molecular and biochemical regulation of phenolic synthesis can be summarised as: (1) carbohydrates are partitioned in a manner ensuring growth; (2) carbohydrates are available for phenolic synthesis mainly during cell differentiation and after leaf maturation as the 'overflow'; (3) synthesis of a particular phenolic compound is specific to cell type and developmental stage; and (4) synthesis of certain phenolic compounds can be induced, independently of cell type, by factors such as wounding, microbial infection, and UV light. Recent advances in the understanding of the regulation of phenolic synthesis raises the question as to whether between-site and temporal variation in the amount and type of plants phenolics is due mostly to selection pressure by herbivores. Interdisciplinary studies by biochemists and ecologists are needed for a better understanding of the regulation of phenolic synthesis and plant-herbivore interactions mediated by secondary metabolites.

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Plant-associated CO2 mediates long-distance host location and foraging behaviour of a root herbivore

eLife ◽

10.7554/elife.65575 ◽

2021 ◽

Vol 10 ◽

Author(s):

Carla CM Arce ◽

Vanitha Theepan ◽

Bernardus CJ Schimmel ◽

Geoffrey Jaffuel ◽

Matthias Erb ◽

...

Keyword(s):

Host Plants ◽

Host Location ◽

Foraging Behaviour ◽

Larval Growth ◽

Insect Herbivores ◽

Long Distance ◽

Herbivore Interactions ◽

Root Herbivore ◽

Plant Herbivore ◽

Dose Dependent

Insect herbivores use different cues to locate host plants. The importance of CO2 in this context is not well understood. We manipulated CO2 perception in western corn rootworm (WCR) larvae through RNAi and studied how CO2 perception impacts their interaction with their host plant. The expression of a carbon dioxide receptor, DvvGr2, is specifically required for dose-dependent larval responses to CO2. Silencing CO2 perception or scrubbing plant-associated CO2 has no effect on the ability of WCR larvae to locate host plants at short distances (<9 cm), but impairs host location at greater distances. WCR larvae preferentially orient and prefer plants that grow in well-fertilized soils compared to plants that grow in nutrient-poor soils, a behaviour that has direct consequences for larval growth and depends on the ability of the larvae to perceive root-emitted CO2. This study unravels how CO2 can mediate plant–herbivore interactions by serving as a distance-dependent host location cue.

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Impact of Raspberry (Rubus idaeus L.) Primocane Tipping on Fruit Yield and Quality

Notulae Botanicae Horti Agrobotanici Cluj-Napoca ◽

10.15835/nbha45210876 ◽

2017 ◽

Vol 45 (2) ◽

pp. 417-424 ◽

Cited By ~ 4

Author(s):

Zala ZORENC ◽

Robert VEBERIC ◽

Darinka KORON ◽

Maja MIKULIC-PETKOVSEK

Keyword(s):

Secondary Metabolites ◽

Fruit Quality ◽

High Performance ◽

Great Influence ◽

High Temperature Stress ◽

Quality Parameters ◽

Rubus Idaeus ◽

Fruit Yield ◽

Primary And Secondary Metabolites ◽

The Impact

High temperature stress, which has been occurring more often in recent years, usually coincides with the flowering of primocane raspberries and causes a negative effect on fruit quality parameters. One of the methods of delaying raspberry flowering and fruit development to avoid high summer temperatures is tipping the young primocanes. The aim of the study was to investigate how this practice affects the fruit characteristics and primary and secondary metabolites of two primocane raspberry cultivars (‘Amira’ and ‘Polka’). For this purpose, we performed primocane tipping on two different dates in late spring and analyzed the berries from three subsequent sampling dates. High performance liquid chromatography-mass spectrometry (HPLC-MS) analyses were used for the identification and quantification of individual phenolic compounds and HPLC analyses for individual sugars and organic acids. Primocane tipping had great influence on the beginning of the harvest season of both cultivars. The impact on fruit yield was insignificant. Sampling date had a greater influence on fruit metabolite contents than did different treatments, with cultivar ‘Polka’ showing a greater response to primocane tipping than cultivar 'Amira'. Based on primary and secondary metabolites, it is difficult to say which treatment provided the best results, since dissimilar patterns were shown at different sampling dates and between cultivars. With negligible differences in fruit quality, primocane tipping was shown to be a good cultivation practice for delaying the production season of raspberries.

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Root volatiles in plant-plant interactions I: Characterization of root sesquiterpene emissions from Centaurea stoebe and their effects on other plants

10.1101/441717 ◽

2018 ◽

Author(s):

Valentin Gfeller ◽

Meret Huber ◽

Christiane Förster ◽

Wei Huang ◽

Tobias G. Köllner ◽

...

Keyword(s):

Spotted Knapweed ◽

Plant Interactions ◽

Centaurea Stoebe ◽

Positive Effects ◽

Root Volatiles ◽

The Impact ◽

Germination And Growth ◽

Plant Plant

AbstractVolatile organic compounds (VOCs) emitted by plant leaves can influence the physiology of neighboring plants. In contrast to interactions above ground, little is known about the role of VOCs in belowground plant-plant interactions. Here, we characterize constitutive root volatile emissions of the spotted knapweed (Centaurea stoebe) and explore the impact of these volatiles on the germination and growth of different sympatric plant species. We show that C. stoebe roots emit high amounts of sesquiterpenes, with estimated release rates of (E)-β-caryophyllene above 3 μg g−1 dw h−1. Sesquiterpene emissions show little variation between different C. stoebe populations, but vary substantially between different Centaurea species. Through root transcriptome sequencing, we identify six root-expressed sesquiterpene synthases (TPSs). Two root-specific TPSs, CsTPS4 and CsTPS5, are sufficient to produce the full blend of emitted root sesquiterpenes. Volatile exposure experiments demonstrate that C. stoebe root volatiles have neutral to positive effects on the germination and growth of different sympatric neighbors. Thus, constitutive root sesquiterpenes produced by two C. stoebe TPSs are associated with facilitation of sympatric neighboring plants. The release of root VOCs may thus influence C. stoebe abundance and plant community structure in nature.

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Coevolution: Plant-Herbivore Interactions and Secondary Metabolites of Plants

Reference Series in Phytochemistry - Co-Evolution of Secondary Metabolites ◽

10.1007/978-3-319-96397-6_41 ◽

2020 ◽

pp. 47-76

Author(s):

Eunice Kariñho-Betancourt

Keyword(s):

Secondary Metabolites ◽

Herbivore Interactions ◽

Plant Herbivore

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

Acta agriculturae Serbica ◽

10.5937/aaser2050129w ◽

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.

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