Testing trade‐offs among growth, regrowth and anti‐herbivore defences in <i>Senecio jacobaea</i>*

Vrieling, Klaas; Jong, Tom J. de; Klinkhamer, Peter G. L.; Meijden, E. van der; Wijk, Catharina A. M. van der Veen‐van

doi:10.1111/j.1570-7458.1996.tb00915.x

Cited by 8 publications

(9 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This is in agreement with the findings of Vrieling et al (1996) for the related weed S. jacobaea. Furthermore, comparative studies of S. jacobaea also found higher defence levels and higher growth in invasive populations than in native ones (Joshi and Vrieling 2005;Stastny et al 2005).…”

Section: S Inaequidenssupporting

confidence: 94%

Palatability to a generalist herbivore, defence and growth of invasive and native Senecio species: testing the evolution of increased competitive ability hypothesis

et al. 2008

View full text Add to dashboard Cite

This paper tests the prediction that introduced plants may become successful invaders because they experience evolutionary changes in growth and defence in their new range [evolution of increased competitive ability hypothesis (EICA)]. Interspecific and intraspecific binary feeding choices were offered to the snail Helix aspersa. The choices were between: (1) plants of the invasive Senecio inaequidens and Senecio pterophorus derived from populations in the introduced range (Europe) and plants of three indigenous species (Senecio jacobea, Senecio vulgaris and Senecio malacitanus) from populations in Europe; (2) plants of the invasive S. inaequidens and S. pterophorus from populations in the introduced range (Europe) and from populations in the native range (South Africa). We did not find a clear pattern of preference for indigenous or alien species of Senecio. However, we found that European invasive populations of S. inaequidens and S. pterophorus were less palatable than South African native populations. Moreover, in contrast to the predictions of the EICA hypothesis, the invasive genotypes of both species also showed a higher total concentration of pyrrolizidine alkaloids, and in the case of S. inaequidens we also found higher growth than in native genotypes. Our results are discussed with respect to the refinement of the EICA hypothesis that takes into account the difference between specialist and generalist herbivores and between qualitative and quantitative defences. We conclude that invasive populations of S. inaequidens and S. pterophorus are less palatable than native populations, suggesting that genetic differentiation associated with founding may occur and contribute to the plants' invasion success by selecting the best-defended genotypes in the introduced range.

show abstract

Section: S Inaequidenssupporting

confidence: 94%

Palatability to a generalist herbivore, defence and growth of invasive and native Senecio species: testing the evolution of increased competitive ability hypothesis

et al. 2008

View full text Add to dashboard Cite

show abstract

“…These findings are in agreement with results from experiments comparing 13 native with 16 introduced S. jacobaeae populations (J. Joshi and K. Vrieling, unpublished observations), and support the evolution of increased competitive ability hypothesis (EICA), which predicts increased investment in life‐history traits such as growth and reproduction in introduced ranges. On average, the more vigorous populations also had higher levels of pyrrolizidine alkaloids, suggesting the absence of a trade‐off between vigour and allocation to PAs, and supporting the conclusion that PAs do not incur a detectable cost (Vrieling & van Wijk 1994a; Vrieling et al . 1996).…”

Section: Discussionsupporting

confidence: 54%

“…A cost of this constitutive, non‐inducible (van Dam et al . 1993) defence has been demonstrated under light‐limiting conditions in the laboratory (Vrieling & van Wijk 1994a); in contrast, no costs were detected under natural conditions (Vrieling & van Wijk 1994b), even when additional defence traits (leaf pubescence, toughness, regrowth capacity) were considered (Vrieling et al . 1996).…”

Section: Methodsmentioning

confidence: 99%

Do vigour of introduced populations and escape from specialist herbivores contribute to invasiveness?

2004

View full text Add to dashboard Cite

Summary1 Plant species may become invasive due to a lack of natural enemies (e.g. herbivores) in their introduced range. Absence of herbivores may result in selection for the loss of costly herbivore-resistance traits, which are expected to show a trade-off with vigour or competitive ability (the evolution of increased competitive ability, or EICA, hypothesis). 2 We conducted a common garden experiment in Switzerland, in which we compared herbivore resistance and vigour of Senecio jacobaea plants exposed to the specialist flea beetle Longitarsus jacobaeae , for four populations originating within the native range (Europe), and four from regions where it had been introduced (New Zealand, USA) and was unaffected by L. jacobaeae . Our predictions were that, compared with plants from the native populations, plants from introduced populations would experience greater herbivory (due to loss of resistance traits), and exhibit more vigorous growth. 3 As expected, we found that introduced S. jacobaea grew larger, and had greater reproductive output, than plants from the native range. Larger plants experienced more feeding damage, and introduced plants were consumed more even when size differences were controlled. Introduced plants also exhibited a greater relative ability to reproduce after damage was sustained, i.e. higher tolerance to herbivory. 4 Contrary to predictions, however, plants from introduced populations had higher total pyrrolizidine alkaloid production (chemical defence against herbivores). 5 Although plants from introduced ranges exhibited life-history traits consistent with EICA predictions, similar phenotypes were common in one of the populations from the native range, suggesting that EICA may not fully explain the invasion success of S. jacobaea . 6 Our results imply that increased competitive ability (vigour) of invasive plants may be associated with changes in resistance as well as tolerance to herbivory, and both types of anti-herbivore defence may need to be examined simultaneously to advance our understanding of invasiveness.

show abstract

“…The negative slope of the regression between shoot to root ratio and PA concentration in S. jacobaea suggests that there is a developmental constraint on the defence level in young plants, and that this constraint may affect growth at a later stage. In established S. jacobaea plants, the shoot to root ratio is correlated with rgr (Vrieling et al 1996;van der Meijden, unpublished data). Moreover, in a field experiment the rgr of the alkaloidpoor breeding line was found to be higher than the one from the alkaloid-rich line, leading to larger rosettes at the end of the first season (Vrieling, unpublished data).…”

Section: Discussionmentioning

confidence: 99%

Pyrrolizidine alkaloid content in Senecio : ontogeny and developmental constraints

2003

Self Cite

View full text Add to dashboard Cite

The ontogeny of pyrrolizidine alkaloid (PA) synthesis and constraints on defence level during the seedling stage were examined in the annual Senecio vulgaris and the monocarpic perennial Senecio jacobaea. In both species, PAs were actively synthesized from the onset of seedling growth so that juvenile stages did not go through an undefended stage. Roots are known to be the exclusive sites where PAs are produced. Root biomass was the single most important biomass parameter explaining variation in total PAs per seedling. All correlation coefficients between relative growth rate and PA concentration were negative, but none was significant. However, a significant negative correlation was found between shoot to root ratio and PA concentration in S. jacobaea seedlings, suggesting a dilution effect of the PAs. Earlier studies have shown that the shoot to root ratio is positively correlated with relative growth rate of established S. jacobaea plants. It is therefore suggested that young S. jacobaea plants with a high shoot to root ratio and hence a high growth capacity necessarily have lower PA defence levels than plants with a low shoot to root ratio.

show abstract

Testing trade‐offs among growth, regrowth and anti‐herbivore defences in *Senecio jacobaea**

Cited by 8 publications

References 15 publications

Palatability to a generalist herbivore, defence and growth of invasive and native Senecio species: testing the evolution of increased competitive ability hypothesis

Palatability to a generalist herbivore, defence and growth of invasive and native Senecio species: testing the evolution of increased competitive ability hypothesis

Do vigour of introduced populations and escape from specialist herbivores contribute to invasiveness?

Pyrrolizidine alkaloid content in Senecio : ontogeny and developmental constraints

Contact Info

Product

Resources

About

Testing trade‐offs among growth, regrowth and anti‐herbivore defences in Senecio jacobaea*

Cited by 8 publications

References 15 publications

Palatability to a generalist herbivore, defence and growth of invasive and native Senecio species: testing the evolution of increased competitive ability hypothesis

Palatability to a generalist herbivore, defence and growth of invasive and native Senecio species: testing the evolution of increased competitive ability hypothesis

Do vigour of introduced populations and escape from specialist herbivores contribute to invasiveness?

Pyrrolizidine alkaloid content in Senecio : ontogeny and developmental constraints

Contact Info

Product

Resources

About

Testing trade‐offs among growth, regrowth and anti‐herbivore defences in *Senecio jacobaea**