1 Introduction
Crop damage caused by insects is a severe problem in agriculture. Moths
(Lepidoptera) are major insect pests [1-3]. The European corn borer
(ECB) Ostrinia nubilalis is the main pest of maize Zea
mays in Europe [4]. It is estimated that in the absence of
treatment, up to 20% of the crop may be lost due to the damage byO. nubilalis larvae [5]. Like other moth species, females ofO. nubilalis produce and release a fatty acid-derived sex
pheromone, which attracts conspecific males for mating [6]. ECB is
polymorphic with respect to its pheromone communication system and two
pheromone races are recognized: the Z-race insects use a 97:3 blend of
(Z )-11-tetradecenyl acetate (Z 11-14:OAc) to
(E )-11-tetradecenyl acetate (E 11-14:OAc), while E-race
insects use a 1:99 blend of the same components [6,7]. On maize in
Europe, the Z-race is most prevalent [8].
Mating disruption has been proven an effective and environmentally
friendly solution for crop protection against moths. For mating
disruption, a more or less species-specific pheromone blend is applied
to the fields or orchards to disrupt mating partner detection and, in
this way, decrease the propagation of the pest species [9,10].
Currently, pheromones for pest management are produced synthetically
from petrol-derived chemicals [11-13]. Chemical synthesis typically
comprises multiple steps, uses toxic chemicals and solvents, and
expensive catalysts. Biotechnological production of several insect
pheromone components has already been established in plants and yeasts
[14-18]. Oleaginous yeast Yarrowia lipolytica is particularly
suitable for production of lepidopteran pheromones due to its naturally
high level of fatty acid biosynthesis. Previously, we produced the
precursor of the major pheromone component of Helicoverpa
armigera (Z 11-16:OH) at 2.5 g/L in Y. lipolytica and
proved the effectiveness of yeast-derived insect pheromone in field
trapping experiments [16].
In this study, we aimed to produce Z 11-14:OAc, the major
pheromone component of the ECB Z-race, using engineered Y.
lipolytica as a host and demonstrate the activity of yeast-derived
pheromone on O. nubilalis males.