Role of Glucosinolates in Insect-Plant Relationships and Multitrophic Interactions

Department of Ecology, Swedish University of Agricultural Sciences, Uppsala S-750 07, Sweden.
Annual Review of Entomology (Impact Factor: 13.73). 10/2008; 54(1):57-83. DOI: 10.1146/annurev.ento.54.110807.090623
Source: PubMed


Glucosinolates present classical examples of plant compounds affecting insect-plant interactions. They are found mainly in the family Brassicaceae, which includes several important crops. More than 120 different glucosinolates are known. The enzyme myrosinase, which is stored in specialized plant cells, converts glucosinolates to the toxic isothiocyanates. Insect herbivores may reduce the toxicity of glucosinolates and their products by excretion, detoxification, or behavioral adaptations. Glucosinolates also affect higher trophic levels, via reduced host or prey quality or because specialist herbivores may sequester glucosinolates for their own defense. There is substantial quantitative and qualitative variation between plant genotypes, tissues, and ontogenetic stages, which poses specific challenges to insect herbivores. Even though glucosinolates are constitutive defenses, their levels are influenced by abiotic and biotic factors including insect damage. Plant breeders may use knowledge on glucosinolates to increase insect resistance in Brassica crops. State-of-the-art techniques, such as mutant analysis and metabolomics, are necessary to identify the exact role of glucosinolates.

Download full-text


Available from: Richard James Hopkins, Oct 05, 2015
105 Reads
    • "Field studies that monitored plant colonization by insects season wide, show that early-season herbivory may enhance the presence of other herbivores, in particular specialists (Van Zandt & Agrawal, 2004; Viswanathan et al., 2005; Poelman et al., 2010). One explanation for this phenomenon may be found in the fact that these specialist herbivores use their food plant-specific secondary chemistry as token stimulus for oviposition (Hopkins et al., 2009). As part of induced resistance to herbivory, often the concentration of these compounds increases and thus these plants become more apparent to specialist herbivores that may impose negative effects on plant fitness (Poelman et al., 2008, 2010). "
    [Show abstract] [Hide abstract]
    ABSTRACT: Plant–insect interactions typically take place in complex settings of interactions among multiple trophic levels as well as multiple species in each trophic level. The complex interaction network may strongly impact on extrapolations of resistance traits to have a defensive function. For example, the induced response plants express to their current attacker often enhances resistance to that attacker, but may make a plant more susceptible to attack by another herbivore. Hence, the defensive function or plant fitness benefit of the response to a single attacker may be misinterpreted from pairwise interactions. Moreover, plant physiological responses to a first stress by herbivory may hamper the response to a second stress and lead to conclusions of maladaptation in plant defence responses. In light of the entire community of attackers and beneficial organisms the plant interacts with, the susceptibility to some attackers may be a consequence of adaptations that reduce fitness costs of herbivory when considering the full sweep of species that affect plant fitness. A similar argumentation may apply for indirect resistance in which predators or parasitoids dampen the effect of herbivores on plants. Plant volatiles that attract third trophic level organisms such as parasitoids may at the same time attract enemies of the parasitoids in the fourth trophic level, hyperparasitoids, which again dampen the effect of parasitoids on herbivores. In addition, the effectiveness of predators and parasitoids may be dependent on habitat complexity. Here, I plea for studies on the full plant-associated community to understand the fitness outcome of an (induced) plant trait and hence coin it induced direct or indirect plant defence.
    Entomologia Experimentalis et Applicata 09/2015; DOI:10.1111/eea.12334 · 1.62 Impact Factor
  • Source
    • "Sendoya et al. (2009) found that Euncia bechina (Hewitson) (Lepidoptera: Nymphalidae) butterflies shift their egg-laying preferences to less risky foliage by using visual cues to determine whether predacious ants are present on particular plants, and this adaptive behavior improves offspring survival. Plants in the Brassicaceae host a broad insect community of both specialist and generalist herbivores (Hopkins et al. 2009; Layman and Lundgren 2015). Many of these herbivores use Brassica-produced glucosinolates to help them identify potential host plants (Hopkins and van Loon 2001; Richards 1940). "
    [Show abstract] [Hide abstract]
    ABSTRACT: Oviposition decisions by herbivorous insects hinge on multiple factors, with some of the most important being enemy-free space and competition for resources. It is important to understand whether and how herbivores and predators can influence the maternal egg-laying preference when they are alone and in combination with host plants. Here, we evaluate whether the presence of aphids (a competitor) or a lady beetle larvae (a predator) influence host plant selection by an ovipositing butterfly. Canola (Brassica napus L.) was the highest quality of three puta-tive Brassicaceae host plants for aphids Myzus persicae (Sulzer) (Hemiptera: Aphididae), while the butterfly Pieris rapae (L.) (Lepidoptera: Pieridae) showed similar survival on all. Canola was used to determine that the presence of a competitor herbivore (aphids) had no effect on butterfly oviposition behavior. However, predators significantly influenced the number of eggs laid on the plants, especially on those plants that had both aphids and a lady beetle larva present in combination. We expect that adult female P. rapae did not lay their eggs on the treatment that involved both herbivorous competition and predation risk, due to the combined risk factors along with the volatile chemicals and aphid alarm pheromones emitted on those plants that contained both the aphids and lady beetle larva.
    Arthropod-Plant Interactions 09/2015; 9:507-514. DOI:10.1007/s11829-015-9392-x · 1.46 Impact Factor
  • Source
    • "Wild cabbage (Brassica oleracea) plants grow naturally along the Atlantic coasts of north-western Europe and belong to the large family Brassicaceae. Plant species within this family all produce glucosinolates (hereafter GS), inducible secondary metabolites that play a role in mediating plantinsect interactions (Gols et al. 2009; Hopkins et al. 2009). GS profiles not only differ among populations (Gols et al. 2008b; Mithen et al. 1995; Moyes et al. 2000; Newton et al. 2009; van Geem et al. 2013), but also between individual plants within a population (Mithen et al. 1995) and between different plant organs of individual plants (Bennett and Wallsgrove 1994). "
    [Show abstract] [Hide abstract]
    ABSTRACT: Plants are attacked by both above- and belowground herbivores. Toxic secondary compounds are part of the chemical defense arsenal of plants against a range of antagonists, and are subject to genetic variation. Plants also produce primary metabolites (amino acids, nutrients, sugars) that function as essential compounds for growth and survival. Wild cabbage populations growing on the Dorset coast of the UK exhibit genetically different chemical defense profiles, even though they are located within a few kilometers of each other. As in other Brassicaceae, the defensive chemicals in wild cabbages constitute, among others, secondary metabolites called glucosinolates. Here, we used five Dorset populations of wild cabbage to study the effect of belowground herbivory by the cabbage root fly on primary and secondary chemistry, and whether differences in chemistry affected the performance of the belowground herbivore. There were significant differences in total root concentrations and chemical profiles of glucosinolates, amino acids, and sugars among the five wild cabbage populations. Glucosinolate concentrations not only differed among the populations, but also were affected by root fly herbivory. Amino acid and sugar concentrations also differed among the populations, but were not affected by root fly herbivory. Overall, population-related differences in plant chemistry were more pronounced for the glucosinolates than for amino acids and sugars. The performance of the root herbivore did not differ among the populations tested. Survival of the root fly was low (<40 %), suggesting that other belowground factors may override potential differences in effects related to primary and secondary chemistry. Electronic supplementary material The online version of this article (doi:10.1007/s10886-015-0605-7) contains supplementary material, which is available to authorized users.
    Journal of Chemical Ecology 08/2015; 41(8). DOI:10.1007/s10886-015-0605-7 · 2.75 Impact Factor
Show more