Affiner les résultats


Collection spécifique


Université de Neuchâtel

Tritrophic interactions on cultivated maize and its wild ancestor "teosinte"

De Lange, Elvira Simone ; Turlings, Ted (Dir.)

Thèse de doctorat : Université de Neuchâtel, 2014.

Modern maize plants (Zea mays ssp. mays, Poaceae) are characterized by large cobs that contain juicy grains, although they have not always had these characteristics. Approximately 9000 years ago, maize was domesticated from teosinte (Z. mays ssp. parviglumis), its closest wild ancestor, which produces much less and much smaller seeds. Teosinte still grows in the wild...

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

Minor effects of two elicitors of insect and pathogen resistance on volatile emissions and parasitism of Spodoptera frugiperda in Mexican maize fields

von Mérey, Georg ; Veyrat, Nathalie ; de Lange, Elvira S. ; Degen, Thomas ; Mahuku, George ; Lopez Valdez, Raymundo ; Turlings, Ted C. J. ; D’Alessandro, Marco

In: Biological Control, 2012, vol. 60, no. 1, p. 7-15

Synthetic elicitors can be used to induce resistance in plants against pathogens and arthropod herbivores. Such compounds may also change the emission of herbivore-induced plant volatiles, which serve as important cues for parasitic wasps to locate their hosts. Therefore, the use of elicitors in the field may affect biological control of insect pests. To test this, we treated maize seedlings...

Université de Neuchâtel

Signal signature of aboveground-induced resistance upon belowground herbivory in maize

Erb, Matthias ; Flors, Victor ; Karlen, Danielle ; de Lange, Elvira S. ; Planchamp, Chantal ; D’Alessandro, Marco ; Turlings, Ted C. J. ; Ton, Jurriaan

In: The Plant Journal, 2009, vol. 59, no. 2, p. 292-302

Plants activate local and systemic defence mechanisms upon exposure to stress. This innate immune response is partially regulated by plant hormones, and involves the accumulation of defensive metabolites. Although local defence reactions to herbivores are well studied, less is known about the impact of root herbivory on shoot defence. Here, we examined the effects of belowground infestation by...

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

Synergies and trade-offs between insect and pathogen resistance in maize leaves and roots

Erb, Matthias ; Balmer, Yves ; de Lange, Elvira S. ; von Merey, Georg ; Planchamp, Chantal ; Robert, Christelle Aurélie Maud ; Röder, Gregory ; Sobhy, Islam ; Zwahlen, Claudia ; Mauch-Mani, Brigitte ; Turlings, Ted C. J.

In: Plant, Cell & Environment, 2011, vol. 34, no. 7, p. 1088-1103

Determining links between plant defence strategies is important to understand plant evolution and to optimize crop breeding strategies. Although several examples of synergies and trade-offs between defence traits are known for plants that are under attack by multiple organisms, few studies have attempted to measure correlations of defensive strategies using specific single attackers. Such links...

Université de Neuchâtel

Attractiveness of Constitutive and Herbivore-Induced Sesquiterpene Blends of Maize to the Parasitic Wasp Cotesia marginiventris (Cresson)

Fontana, Anna ; Held, Matthias ; Fantaye, Chalie A. ; Turlings, Ted C. J. ; Degenhardt, Jörg ; Gershenzon, Jonathan

In: Journal of Chemical Ecology, 2011, vol. 37, no. 6, p. 582-591

Plant volatile compounds induced by herbivore attack have been demonstrated to provide a signal to herbivore enemies such as parasitic wasps that use these volatiles to locate their hosts. However, in addition to herbivore-induced volatiles, plants often release volatiles constitutively. We assessed the interaction between herbivore-induced and constitutively released volatiles of maize in the...

Université de Neuchâtel

White lupin leads to increased maize yield through a soil fertility-independent mechanism: a new candidate for fighting Striga hermonthica infestation?

Weisskopf, Laure ; Akello, Pollycarp ; Milleret, Roxane ; Khan, Zeyaur R. ; Schulthess, Fritz ; Gobat, Jean-Michel ; Le Bayon, Renée-Claire

In: Plant and Soil, 2009, vol. 319, no. 1-2, p. 101-114

Nitrogen (N)-deficiency and lack of phosphorus (P) availability are major constraints to maize yields in Western Kenya. In a two-season field study in the lake Victoria basin, we tested the capacity of white lupin (Lupinus albus (L.), cv. Ultra), as a nitrogen-fixing crop with a highly efficient P-acquisition capacity, to increase maize yields when used as a companion or cover crop,...

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...