Seasonal and herbivore-induced dynamics of foliar glucosinolates in wild cabbage (Brassica oleracea)

Abstract

Levels of plant secondary metabolites are not static and often change in relation to plant ontogeny. They also respond to abiotic and biotic changes in the environment, e.g., they often increase in response to biotic stress, such as herbivory. In contrast with short-lived annual plant species, especially those with growing periods of less than 2–3 months, investment in defensive compounds of vegetative tissues in biennial and perennial species may also vary over the course of an entire growing season. In garden experiments, we investigated the dynamics of secondary metabolites, i.e. glucosinolates (GSLs) in the perennial wild cabbage (Brassica oleracea), which was grown from seeds originating from three populations that differ in GSL chemistry. We compared temporal long-term dynamics of GSLs over the course of two growing seasons and short-term dynamics in response to herbivory by Pieris rapae caterpillars in a more controlled greenhouse experiment. Long-term dynamics differed for aliphatic GSLs (gradual increase from May to December) and indole GSLs (rapid increase until mid-summer after which concentrations decreased or stabilized). In spring, GSL levels in new shoots were similar to those found in the previous year. Short-term dynamics in response to herbivory primarily affected indole GSLs, which increased during the 2-week feeding period by P. rapae. Herbivore-induced changes in the concentrations of aliphatic GSLs were population-specific and their concentrations were found to increase in primarily one population only. We discuss our results considering the biology and ecology of wild cabbage.Electronic supplementary materialThe online version of this article (10.1007/s00049-018-0258-4) contains supplementary material, which is available to authorized users.

Growing Conditions Affect the Phytochemical Composition of Edible Wall Rocket (Diplotaxis erucoides)

“…However, both AA and TP had lower correlations with the content of SIN. As with AA and phenolic phytochemicals, the accumulation of glucosinolates in plant tissues is part of the plant response mechanism against abiotic stress conditions and can therefore be affected by environmental factors such as light intensity, season or fertilization [16,27,41], but it is also highly related to the biotic stress by pests and pathogens [16,27]. The combined effect of both biotic and abiotic stress could be responsible for this lower correlation.…”

“…In fact, both vitamin C and phenolic compounds are potent antioxidants against plant oxidative stress, and such compounds could be also involved in reducing the risk of different illnesses such as cardiovascular diseases, hepathotoxicity and general inflammation risks [11][12][13][14]; in addition, vitamin C is an essential microelement with antiscorbutic activity [15]. Glucosinolates (GSLs) are secondary metabolites from Brassicaceae and other families within the Brassicales order [16]. The enzymatic hydrolysis of GSLs releases volatile compounds that are responsible of the bitter and pungent flavor of Brassicaceae species [17].…”

Two‐tier morpho‐chemical defence tactic inAethionemavia fruit morph plasticity and glucosinolates allocation in diaspores

“…Plant defence compounds are not equally distributed within a plant but differ in concentrations between tissues and ontogenetic stages (Gols et al, ). According to the optimal defence theory, defensive anticipins should be distributed in an optimal way to protect tissues with high fitness values and a higher probability of being attacked with priority (McKey, ; Zangerl & Bazzaz, ).…”

Resistance to three thrips species in Capsicum spp. depends on site conditions and geographic regions

“…During summer, an accession of this plant species was found to be resistant to the flea beetle Phyllotreta nemorum , but gradually lost its resistance with the onset of fall which was related to changes in plant hormone levels (Agerbirk et al, ). In wild cabbage ( Brassica oleracea ), the concentrations of glucosinolates, which are secondary metabolites acting as chemical defences to insects, increased from summer to winter (Gols et al, ). Possibly seasonal variation may play a role in modulating resistance to thrips in Capsicum .…”