Natural variation of phenolic glycosides in Populus tremula and resistance to the leaf miner Phyllocnistris labyrinthella.

BENEDICTE ALBRECTSEN, VIRGINIA LUQUEZ, JOHANNA WITZELL, STEFAN JANSSON.

Visegrád, Hungría

Conferencia; Third EPSO Conference: Plant Dynamics: from molecules to ecosystems.; 2006

European Plant Science Organization

Abstract Natural Variation of phenolic glycosides in Populus tremula and resistance to the leaf miner Phyllocnistris labyrinthella.   Variation in plant resistance against herbivores is often attributes to differences in secondary chemistry. Several studies of Salicerous species have linked leaf concentrations of phenolic glycosides to herbivore resistance. In Swedish aspen (Populus tremula) linkage disequilibrium is very low but the level of nucleotide poplymorphism is high and consequently Swedish aspen may be considered as one panmictic population, which facilitates associative studies on clone characteristics. We present natural variation of phenolic glycosides in leaves of 48 swedish aspen clones that origin from latitudes between 55 and 66 º N. Leaf chemistry was assessed from clones that had been grown under greenhouse conditions and the response and the response of the mining moth Phyllocnistris labyrinthella  was scored in the same clones under field conditions in two common gardens at northern and southern latitudes (respectively 55.9 and 63.4 N). The Expression of phenolics compounds varied highly among the clones. Of eleven identified phenolics, catechin, cinnamic acid and a salicortin derivative showed the strongest clinal pattern with latitude and temperature at place of origin, indicating that aspen secondary chemistry may be under genetic control and has adapted to local conditions. Phyllocnistris labyrinthella. Showed opposite clinal trends in the two gardens and were not strongly related to the average clone phenolic profile. Phenological differences among the clones in the gardens are offered as an explanation.