Ecological trade-offs between jasmonic acid-dependent direct and indirect plant defences in tritrophic interactions

State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100080, China.
New Phytologist (Impact Factor: 7.67). 10/2010; 189(2):557-67. DOI: 10.1111/j.1469-8137.2010.03491.x
Source: PubMed

ABSTRACT Recent studies on plants genetically modified in jasmonic acid (JA) signalling support the hypothesis that the jasmonate family of oxylipins plays an important role in mediating direct and indirect plant defences. However, the interaction of two modes of defence in tritrophic systems is largely unknown.

In this study, we examined the preference and performance of a herbivorous leafminer (Liriomyza huidobrensis) and its parasitic wasp (Opius dissitus) on three tomato genotypes: a wild-type (WT) plant, a JA biosynthesis (spr2) mutant, and a JA-overexpression 35S::prosys plant. Their proteinase inhibitor production and volatile emission were used as direct and indirect defence factors to evaluate the responses of leafminers and parasitoids.

Here, we show that although spr2 mutant plants are compromised in direct defence against the larval leafminers and in attracting parasitoids, they are less attractive to adult flies compared with WT plants. Moreover, in comparison to other genotypes, the 35S::prosys plant displays greater direct and constitutive indirect defences, but reduced success of parasitism by parasitoids.

Taken together, these results suggest that there are distinguished ecological trade-offs between JA-dependent direct and indirect defences in genetically modified plants whose fitness should be assessed in tritrophic systems and under natural conditions.

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Available from: Chuanyou Li, Aug 20, 2015
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    • "However, the phytohormones JA and SA are also known to regulate the production of plant volatiles (Dicke et al., 1999; Ozawa et al., 2000; Lou et al., 2005). Herbivoryinduced plant volatiles (HIPVs) play vital roles in enabling herbivores and their natural enemies to locate their food from a distance (Dicke et al., 1990; Turlings et al., 1995; Bruce et al., 2005; Wei et al., 2007; Dicke and Baldwin, 2010; Bruce and Pickett, 2011). Although a few studies have explored such negative SA–JA crosstalk in plant–herbivore–natural enemy interactions (Zhang et al., 2009; Thaler et al., 2010), to date it is largely unknown how SA–JA negative crosstalk affects host-plant selection behaviour of herbivores. "
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    • "In other systems, a key role of JA signalling pathway in regulating indirect plant defence, that is, the volatile-mediated attraction of parasitoids or predators, has been well demonstrated (Thaler et al. 2002; Ament et al. 2004; Bruce et al. 2008; Girling et al. 2008; Bruinsma et al. 2009; Wei et al. 2011) and a few studies have shown that JA-dependent indirect plant defence offers benefits under field conditions (Thaler 1999; Heil et al. 2001). As yet, the role of other signalling pathways in attracting natural enemies of herbivores was not known, although it has been indicated that the SA-signalling plays a role in regulating certain herbivore-induced plant volatile emissions (Ozawa et al. 2000; Van Poecke & Dicke 2002). "
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