Plant-pollinator communication under drought stress

Plants are the most important primary producers and thus crucial for the functioning of ecosystems. The changing climatic conditions affect plants in natural systems as well as in agriculture. Predicted water scarcity will not only affect the growth and development of plants and the agricultural production, but also the interactions of plants with other organisms, such as pollinators. Flower scent is important for the communication between plants and pollinators. So far, it is unclear how short- and long-term drought affect the synthesis of floral scents and the communication with pollinators. In the past, drought has led to major crop losses in the Styrian oil pumpkin (Cucurbita pepo pepo var. styriaca Greb.). Therefore, we want to address the following questions: 1) Do short- and long-term drought stress affect the scent released by female and male flowers? 2) What influence does drought have on the biosynthesis of floral scents? 3) Does drought stress alter the quantity and composition of nectar? 4) Which floral scents trigger physiological responses in the antennae of pollinators (bumblebees and honeybees) of cucurbit flowers? 5) How does drought stress affect the attraction of pollinators by floral scents? In our study, we will determine for the first time the effects of (short- and long-term) drought on the biosynthesis of floral scents and on the olfactory attractiveness of flowers to pollinators.