Université de Neuchâtel

Above- and belowground antifungal resistance in maize : aspects of organ-specific defense

Balmer, Dirk ; Mauch-Mani, Brigitte (Dir.)

Thèse de doctorat : Université de Neuchâtel, 2013.

The hemibiotrophic fungus Colletotrichum graminicola causes devastating anthracnose on maize (Zea mays) and is responsible for annual losses of up to 1 billion dollars in the U.S. A key factor for its success is the capability to infect different plant organs. The predominant symptoms are leaf blight and stalk rot, but C. graminicola also infects roots. The vast majority of...

Université de Neuchâtel

The role of abscisic acid and water stress in root herbivore-induced leaf resistance

Erb, Matthias ; Köllner, Tobias G. ; Degenhardt, Jörg ; Zwahlen, Claudia ; Hibbard, Bruce E. ; Turlings, Ted C. J.

In: New Phytologist, 2011, vol. 189, no. 1, p. 308-320

Herbivore-induced systemic resistance occurs in many plants and is commonly assumed to be adaptive. The mechanisms triggered by leaf-herbivores that lead to systemic resistance are largely understood, but it remains unknown how and why root herbivory also increases resistance in leaves. To resolve this, we investigated the mechanism by which the root herbivore Diabrotica...

Université de Neuchâtel

Sequence of arrival determines plant-mediated interactions between herbivores

Erb, Matthias ; Robert, Christelle Aurélie Maud ; Hibbard, Bruce E. ; Turlings, Ted C. J.

In: Journal of Ecology, 2011, vol. 99, no. 1, p. 7-15

1. Induced changes in plant quality can mediate indirect interactions between herbivores. Although the sequence of attack by different herbivores has been shown to influence plant responses, little is known about how this affects the herbivores themselves. 2. We therefore investigated how induction by the leaf herbivore Spodoptera frugiperda influences resistance of teosinte...

Université de Neuchâtel

Modification of plant resistance and metabolism by above- and belowground herbivores

Erb, Matthias ; Turlings, Théodor (Dir.)

Thèse de doctorat : Université de Neuchâtel, 2009 ; Th. 2084.

Plants are often attacked by above- and belowground herbivores. As a result, they have evolved defense mechanisms to protect both their roots and shoot. However, physiological processes in roots and shoots are tightly connected, and attack of one of these plant parts can dramatically alter primary and secondary metabolism of the other (chapter 1). It is therefore important to understand how the...

Université de Neuchâtel

Fungal Infection Reduces Herbivore-Induced Plant Volatiles of Maize but does not Affect Naïve Parasitoids

Rostás, Michael ; Ton, Jurriaan ; Mauch-Mani, Brigitte ; Turlings, Ted C. J.

In: Journal of Chemical Ecology, 2006, vol. 32, no. 9, p. 1897-1909

Plants attacked by insects release volatile compounds that attract the herbivores' natural enemies. This so-called indirect defense is plastic and may be affected by an array of biotic and abiotic factors. We investigated the effect of fungal infection as a biotic stress agent on the emission of herbivore-induced volatiles and the possible consequences for the attraction of two parasitoid...

Université de Neuchâtel

An elicitor in caterpillar oral secretions that induces corn seedlings to emit chemical signals attractive to parasitic wasps

Turlings, Ted C. J. ; McCall, Philip J. ; Alborn, Hans ; Tumlinson, James H.

In: Journal of Chemical Ecology, 1993, vol. 19, p. 411 - 425

Regurgitate of corn-fed beet armyworm (BAW) caterpillars, Spodoptera exigua, when applied to damaged sites of corn (Zea mays) seedlings, causes the release of relatively large amounts of terpenes by the seedlings several hours later. This plant response could be induced by merely placing the cut stem of seedlings in a solution of BAW regurgitate for 12 hr, a response that could not...

Université de Neuchâtel

Response of natural populations of predators and parasitoids to artificially induced volatile emissions in maize plants (Zea mays L.)

Bernasconi Ockroy, Marco L. ; Turlings, Ted C. J. ; Edwards, Peter J. ; Fritzsche-Hoballah ; Ambrosetti, Lara ; Bassetti, Paolo ; Dorn, Silvia

In: Agricultural and Forest Entomology, 2001, vol. 3, p. 201-209

1 In response to herbivore attack, maize plants (Zea mays L.) emit a specific blend of induced volatiles. Artificial damage and subsequent treatment of the damaged site with caterpillar regurgitant induces the same response. The induced volatile chemicals are known to be highly attractive to several parasitoids of herbivores in laboratory bioassays, but very limited information is...